Method and system for engine block thermal conductivity

Abstract

The present application relates to methods and systems for engine block thermal conductivity and provides methods and systems for a coating of a portion of a shaped combustion chamber of an engine block. In one example, the engine block includes a first coating having a higher thermal conductivity than a conductivity of the engine block arranged in an upper region of the combustion chamber and a second coating having a lower thermal conductivity than a conductivity of the engine block arranged in a lower region of the combustion chamber, and wherein the second coating touches the first coating.

Description

[0001] Cross-references to related applications

[0002] This application claims priority to German patent application No. 102018202540.1, filed on February 20, 2018. For all purposes, the entire contents of the above-mentioned application are incorporated herein by reference in their entirety. Technical Field

[0003] The present invention generally relates to enhancing the thermal conductivity of the engine block near the piston in the combustion chamber. Background Technology

[0004] Typically, for internal combustion engines, the crankcase or engine block can be manufactured from aluminum or aluminum alloys using a high-pressure die-casting (HPDC) process. Compared to cast iron, the HPDC process offers weight reduction and enhanced heat transfer.

[0005] To meet tribological requirements, it is also known to use cylinder liners made of gray cast iron with a wall thickness typically between 2mm and 4mm in engine blocks made of aluminum or aluminum alloys. In this case, some advantages regarding waste heat consumption are lost, as the waste heat consumption is approximately 40-50... The thermal conductivity of gray cast iron is only about 140 that of aluminum. It is a small fraction of the thermal conductivity.

[0006] Therefore, cylinder liners made of aluminum with high thermal conductivity have also been used. According to the article “Thermal spraying of cylinder bores with the Plasma Transferred Wire Arc process” in Surface and Coatings Technology, Vol. 202, Edition 18, June 15, 2008, pp. 4438-4443, in “Thermal spraying of cylinder bores with the Plasma Transferred Wire Arc process”, Vol. 202, Edition 18, June 15, 2008, pp. 4438-4443, in “Surface and Coatings Technology”, Vol. 202, 18th edition, June 15, 2008, pp. 4438-4443, it is known that automotive engine blocks, composed of hypoeutectic aluminum-silicon alloys, are typically equipped with cast iron sleeves to obtain cylinder bore surfaces that meet tribological requirements. Thermally sprayed cylinder bore surfaces are described therein as a promising alternative to gray cast iron liners. Atmospheric plasma spraying (APS) of cylinder bore surfaces composed of low-alloy C-grade steel has demonstrated its ability to reduce frictional losses in engines. The additional potential for reducing frictional losses is unprecedented and is attributed to high-alloy surface materials on an iron-based substrate. This article describes the development of such materials and their use on inner walls via thermal plasma transfer wire arc coating (PTWA). When treated by thermal spraying, the feed material results in a partially amorphous coating with nanoscale deposits of embedded expansion. Coatings were deposited on the inner walls of test bushings composed of aluminum EN AW 6060 and on the cylinder bore walls of a 4-cylinder inline engine. Prior to coating, all surfaces to be coated were pretreated by a novel type of precision boring process to produce a surface morphology that enables coating adhesion. The microstructure of the coating was analyzed by optical microscopy, hardness testing, and transmission electron microscopy, and the oil retention capacity of the honed surfaces was determined.

[0007] In other alternative methods, the use of cylinder liners is omitted, and the cylinder walls of the engine block are coated to achieve, for example, the desired friction and wear resistance. The coating is designed with regard to the selection and arrangement of materials based on the desired function.

[0008] To manufacture the coating, a thermal process is used, in which special attention must be paid to the reliable application of the coating to the cylinder wall to be coated. Specific processes and apparatus were proposed for this purpose in the previous examples.

[0009] For example, WO2016 / 202511A1 describes a thermal spraying method and apparatus for coating the inner surface of a cylinder of an internal combustion engine or piston engine, wherein the method is characterized by applying a thermally sprayed coating to the inner surface of the cylinder and optically detecting the area around the spray nozzle (specifically, the space outside the spray nozzle) via an optical sensing device. In this case, if particles of the spraying material supplied to the spray burner are detected by the optical sensing device in the monitoring area outside the spray nozzle, an error in the coating process is assumed. For example, the thermal spraying process is formed by a known plasma transfer wire arc spraying (PTWA) process or a rotating monofilament (RSW) process.

[0010] DE102017103715A1 proposes a coating for cylinder liners or cylinder walls with a functional layer that, for its variable porosity, ensures that different lubrication requirements in different areas of the cylinder bore are met.

[0011] For example, an engine block made of cast iron, aluminum, magnesium, or their alloys can have a body having at least one cylindrical engine bore wall with a longitudinal axis and a variable coating of thickness extending along the longitudinal axis. The coating can have an intermediate region and first and second end regions, and multiple pores can be distributed throughout the coating thickness. The intermediate region can have an average porosity different from one or both of the end regions. The method can involve the thermal spraying of a coating with a first porosity in the intermediate longitudinal region of the bore and the spraying of a coating with a second porosity in one or more end regions of the bore. The coating can be any coating that provides sufficient mechanical strength, hardness, density, wear properties, friction, fatigue strength, and / or thermal conductivity for the cylinder bore, and can also be formed, particularly, of iron, steel, other metals, or nonmetals (such as ceramic coatings, polymer coatings, or amorphous carbon coatings). The first porosity can be greater than the second porosity, and both the first and second porosities can be formed during the spraying step. One or both end regions can have an average porosity between 0.1% and 3%. The intermediate region can have an average porosity of at least 5%. In this case, the pores can act as depressions for the lubricant, thus providing lubrication under rough conditions and improving the lubricant film thickness.

[0012] The application of coatings on cylinder walls to influence heat flow during the operation of internal combustion engines is also known.

[0013] For example, EP3228852A1 proposes an internal combustion engine with a combustion chamber and a coating. The combustion chamber is surrounded by at least one inner wall of a cylinder bore, cylinder head, valves, and piston. The coating is applied to at least a portion of the inner wall of the combustion chamber via a flame spraying process, wherein the thermal conductivity of the coating at room temperature is lower than that of the cylinder block, cylinder head, valves, and piston. In this case, the thermal conductivity of the coating, for example, which may comprise a quasi-crystalline metallic alloy (particularly an Al-Cu-Fe based alloy or metallic glass), is reversibly increased with increasing coating temperature, and the heat capacity per unit area of ​​the coating is greater than 0. And less than or equal to 4.2 Therefore, the effect of minimizing cooling losses in the combustion chamber and thus minimizing fuel consumption is achieved, while at the same time, knocking in the internal combustion engine can be reduced.

[0014] JP4812883B2 describes a cylinder liner for use in casting and in cylinder blocks made of aluminum alloy, wherein a layer having a thermal conductivity lower than that of at least one of the cylinder block and the cylinder liner is formed in the axial direction toward the lower end of the intermediate section of the cylinder liner. This layer may consist, for example, of a sprayed coating of ceramic material; in this case, alumina is used as the ceramic material. This layer is formed via thermal spraying (e.g., via plasma spraying or high-velocity oxygen fuel spraying (HVOF)). Due to the low thermal conductivity layer, there should be a possibility of undesirable temperature drops at the lower end of the cylinder liner during cylinder block operation, which could lead to increased viscosity of the lubricating oil and thus higher fuel consumption.

[0015] Furthermore, JP2016205215A proposes a method for manufacturing cylinder blocks in which the outer peripheral wall of the upper portion of the cylinder bore has a higher thermal conductivity coefficient in the axial direction compared to the lower portion of the cylinder bore. This method eliminates the need for any complex steps involving the creation of cylinder liners with different thermal conductivity coefficients in the axial direction on a casting mold for the cylinder block. In this method, the cylinder bore is designed to have a standard inner diameter by forming the cylinder block body, for example, from an aluminum alloy, such that the inner diameter is formed in the lower portion of the bore to create a cylinder bore with an inner diameter larger than that in the upper portion. Subsequently, a material with low thermal conductivity (e.g., an iron-based material with a thermal conductivity coefficient lower than that of the material forming the cylinder block body) is flame-sprayed onto the first and second peripheral wall surfaces defining the cylinder bore of the cylinder block body to form a sprayed coating, wherein the sprayed coating on the first peripheral wall is thicker than that on the second peripheral wall.

[0016] Furthermore, US7,685,987B2 describes cylinder liners, for example, made of cast iron and used in cylinder blocks composed of aluminum alloys. The cylinder liner has an outer peripheral surface and upper, middle, and lower sections in the axial direction of the cylinder liner. For example, a high thermal conductivity layer made of an aluminum-silicon alloy is formed in the section corresponding to the upper section of the outer peripheral surface, and a low thermal conductivity layer is formed in the section corresponding to the lower section of the outer peripheral surface. A sprayed coating mainly composed of ceramic materials such as alumina and zirconium oxide can be used as the material for the low thermal conductivity layer. Alternatively, the low thermal conductivity layer can be formed by a sprayed coating of a material on an iron base containing oxides and multiple pores. The high thermal conductivity layer and the low thermal conductivity layer are laminated in the section corresponding to the middle section of the outer peripheral surface, thus forming a laminated layer section. Therefore, the temperature difference along the axial direction of the cylinder is reduced, and thus fuel consumption can be reduced.

[0017] Given the previous examples, the following areas of the piston path of an internal combustion engine still offer room for improvement in thermal design and increased waste heat flow: the piston path is arranged on the inner wall of the cast cylinder liner in the engine block or on the inner wall of the cylinder bore of the engine block of an internal combustion engine, especially one having an engine block made of aluminum or at least an aluminum alloy. Summary of the Invention

[0018] In one example, the problem described above can be addressed by an engine block comprising a first coating and a second coating. The first coating is disposed on the inner surface of the cylinder near the piston's top dead center position, and the second coating is disposed on the inner surface near the piston's bottom dead center position. The first coating comprises a hypereutectic aluminum-silicon alloy, and the second coating comprises an iron-based alloy having a lower thermal conductivity than both the first coating and the inner surface. In this way, the thermal conductivity in the combustion chamber can be enhanced to promote heat dissipation or heat retention as needed.

[0019] It should be understood that the above description of the invention is intended to introduce some concepts in a simplified form, which are further described in the specific embodiments. This does not imply the identification of the key or essential features of the claimed subject matter, the scope of which is uniquely defined by the appended claims. Furthermore, the claimed subject matter is not limited to embodiments that address any shortcomings mentioned above or in any part of this disclosure. Attached Figure Description

[0020] Figure 1 A schematic diagram of a portion of the engine block is shown in cross-sectional view.

[0021] Figure 2 The details of the engine block are illustrated in a schematic sectional side view.

[0022] Figure 3 The illustration shows a schematic diagram detailing an alternative embodiment of an engine block.

[0023] Figure 4 The illustration shows a schematic perspective view of the cylinder bore in the engine block.

[0024] Figure 5 The illustration shows a schematic perspective view of the cylinder bore in an alternative embodiment of an engine block.

[0025] Figure 6 The schematic sectional side view illustrates details of another alternative embodiment of the engine block.

[0026] Figure 7 The schematic sectional side view illustrates details of an additional alternative embodiment of the engine block.

[0027] Figures 1-7 It is drawn approximately to scale, but other relative dimensions can be used if needed.

[0028] Figure 8 The diagram illustrates an engine comprising at least one cylinder arranged in a hybrid vehicle system.

[0029] Figure 9 The illustration shows a method for applying a first coating and a second coating to a portion of the combustion chamber associated with the engine block.

[0030] Figure 10 The illustration shows an example combustion chamber in which the piston is set to oscillate. Detailed Implementation

[0031] The following description relates to systems and methods for an engine block having an inner surface comprising a shaped combustion chamber, wherein a first coating and a second coating are disposed on the inner surface of the combustion chamber. Figure 1 A schematic diagram of a portion of the engine block is shown in cross-sectional view. Figure 2 The details of the engine block are illustrated in a schematic sectional side view. Figure 3 The illustration shows a schematic diagram detailing an alternative embodiment of an engine block. Figure 4 The illustration shows a schematic perspective view of the cylinder bore in the engine block. Figure 5 The illustration shows a schematic perspective view of the cylinder bore in an alternative embodiment of an engine block. Figure 6 The schematic sectional side view illustrates details of another alternative embodiment of the engine block. Figure 7 The schematic sectional side view illustrates details of an additional alternative embodiment of the engine block. Figure 8 The diagram illustrates an engine comprising at least one cylinder arranged in a hybrid vehicle system. Figure 9 The illustration shows a method for applying a first coating and a second coating to a portion of the combustion chamber associated with the cylinder block. Figure 10 The illustration shows an example combustion chamber in which the piston is set to oscillate.

[0032] This disclosure aims to provide an engine block for an internal combustion engine having at least one piston path, composed of aluminum or at least an aluminum alloy. The heat flow from waste heat generated during operation of the internal combustion engine is optimized for thermal conductivity properties. More specifically, the thermal properties of the engine block are enhanced to promote heat retention and heat dissipation in desired regions, wherein heat retention is preferentially considered in the lower region of the engine block distal to the cylinder head, and heat dissipation is preferentially considered in the upper region of the engine block proximal to the cylinder head.

[0033] The engine block of the present disclosure for an internal combustion engine has at least one cylindrical piston path with a longitudinal axis, which is surrounded by the engine block in at least the operating state. The piston path is particularly used to guide the piston along the longitudinal axis in the operating state of the engine block. The engine block can be made, in particular, of aluminum or at least an aluminum alloy. Furthermore, the engine block can be manufactured in a high-pressure die-casting (HPDC) process.

[0034] In one embodiment, the piston path in the segment near top dead center has a first extensive internal coating that has a higher thermal conductivity than the radially adjacent material about the longitudinal axis, wherein the radially adjacent material may correspond to the engine block material. Furthermore, the piston path in the segment near bottom dead center has a second extensive internal coating that has a lower thermal conductivity than the radially adjacent material about the longitudinal axis, wherein the radially adjacent material may correspond to the engine block material. In one example, the engine block material radially adjacent to the first extensive internal coating and the engine block material radially adjacent to the second extensive internal coating are substantially identical.

[0035] The terms “first,” “second,” etc., used in this application are for distinguishing purposes only. Specifically, the order or priority of the objects mentioned by these terms is not implied by their use.

[0036] The coating on at least one piston path allows for improved dissipation of process heat from the upper region of the piston path to the provided cooling fluid channels (such as the cooling jacket of the combustion chamber). Therefore, knock can be preempted even under high specific power output conditions in the engine block. Furthermore, the coating on at least one piston path provides thermal insulation to the lower region of the piston path. This is desirable to mitigate temperature drops in this region, thus improving the thermal efficiency of the engine block and reducing losses due to increased lubricant viscosity in the lower region of the piston path. Both effects advantageously result in lower fuel consumption and lower emissions.

[0037] The upper region near the top dead center contains a coating with a thermal conductivity higher than that of the radially adjacent materials of the engine block. The lower region near the bottom dead center contains a coating with a thermal conductivity lower than that of the radially adjacent materials of the engine block. Therefore, the thermal conductivity of the coating in the upper region is higher than that in the lower region, where the thermal conductivity of the coating in the upper region is greater than that of the axially adjacent materials, which correspond to the thermal conductivity of the coating in the lower region. Furthermore, it may be desirable for the thermal conductivity of the coating in the lower region to be lower than that of the radially adjacent materials of the engine block to mitigate heat transfer from the coating in the upper region to the coating in the lower region. By doing so, thermal insulation of the lower region of the piston path can be achieved.

[0038] The proposed coating for the piston path of the engine block of an internal combustion engine can be used on an engine block made of aluminum or at least an aluminum alloy.

[0039] In the cold operating state, at least one piston path may include a conical widening, at least in the section near the bottom dead center. Due to the higher thermal expansion in the upper section near the top dead center, a cylindrical piston path in the hot operating state can be achieved via a suitable conical widening during the transition from the cold to the hot operating state. This reduces frictional losses along the piston path, enabling a dimensionally optimized piston path with low frictional losses, combined with the desired thermal insulation of the lower section of the piston path.

[0040] In some embodiments of the engine block, at least one piston path is formed by the inner wall of the cylinder bore or the inner surface of the cylinder liner in the engine block. When the inner wall of the cylinder bore in the engine block is coated, it is possible to avoid inserting the cylinder liner into the casting mold of the engine block (e.g., into a pressure casting mold) during engine block manufacturing. Advantages regarding installation space can also be achieved by avoiding the cylinder liner.

[0041] If cylinder liners are used, the inner surface of the cylinder liner can advantageously provide a void-free surface for receiving the proposed coating. For example, the cylinder liner can be made of a high thermal conductivity aluminum pressure-cast alloy (e.g., A226 (EN AC-AlSi9Cu3(Fe), with 110-120...). (Thermal conductivity) is used in manufacturing.

[0042] The first internal coating preferably comprises a hypereutectic aluminum-silicon alloy having at least 12% silicon. In this way, in addition to high heat dissipation (approximately 140...), In addition to thermal conductivity, it can also achieve favorable tribological properties and high wear resistance in the section of the piston path near the top dead center.

[0043] The second internal coating preferably comprises an iron-based alloy. Through suitable embodiments of the coating process, the iron-based alloy can have a microcrystalline structure with numerous defects, porosity, and a high proportion of low thermal conductivity oxides, thus achieving a low thermal conductivity for the second internal coating. In one example, the defects in the second internal coating may include one or more surface features such as protrusions, grooves, etchings, etc., making the surface of the second internal coating rough and uneven. In this way, a metal-based thermal barrier coating with advantageous tribological properties can be provided in the lower section near the bottom dead center.

[0044] A portion of the second internal coating may at least partially comprise an iron-based nanocomposite material. Due to its nanostructure, the second internal coating can possess good tribological properties and also have approximately 2 Its relatively low thermal conductivity.

[0045] In a preferred embodiment of the engine block, a first internal coating extends along the longitudinal axis in a region of rotational angles of the internal combustion engine between 5° and 50° before and after the top dead center position. Additionally or alternatively, a first internal coating with a higher thermal conductivity than a second internal coating may be arranged within a rotational range between 20° and 40° before and after the top dead center position. By doing so, the first internal coating extends along the longitudinal axis in a region corresponding to the upper 25% and 15% of the piston stroke. By coupling the extent of the first internal coating to the ignition point of the engine block, i.e., in the upper region of the piston stroke, effective heat dissipation can be ensured in areas generating high process heat. The second internal coating is preferably adjacent to the first internal coating and thus arranged along the longitudinal axis from the bottom dead center position, preferably adjacent to the first internal coating. Therefore, if the first internal coating covers the upper 15% of the engine block, then the second internal coating can cover the remaining lower 85% of the engine block. In some examples, additionally or alternatively, the first and second inner coatings may overlap, such that the first inner coating covers the upper 15% and the second inner coating covers the lower 88%, resulting in a 3% overlap between the first and second inner coatings. In this way, the second inner coating can cover a larger surface area of ​​the engine block associated with the combustion chamber than the first inner coating.

[0046] In another aspect of this disclosure is a method for manufacturing an engine block according to this disclosure. The method may include manufacturing a first extensive internal coating on a roughened piston path via a thermal process using an aluminum-silicon alloy having a silicon content of at least 12% as a coating material; manufacturing a second extensive internal coating on the roughened piston path via a thermal process using an iron-based material as a coating material; and removing the first and second extensive internal coatings to predetermined desired dimensions for dimensional trimming of the piston path from the roughened piston path.

[0047] Thermal processes that can be used to manufacture coatings, but are not limited to, can be designed as thermal spraying processes (laser spraying, rotating single wire (RSW) spraying, plasma transfer wire arc (PTWA) spraying, plasma spraying (atmosphere, protective gas) wire flame spraying, high-velocity oxygen fuel (HVOF) flame spraying) or designed as deposition welding processes (laser deposition welding, laser cladding).

[0048] In one example, the first extensive internal coating is fabricated via a laser deposition welding process or a rotating monofilament (RSW) process.

[0049] In one example, the second internal extensive coating is manufactured via a rotating monofilament (RSW) process.

[0050] Therefore, the first and second internal coatings can be manufactured in an efficient and time-saving manner and have good adhesion to rough piston paths.

[0051] The step of removing the first and second extensive internal coatings downwards by a predetermined desired dimension is performed via honing. In this way, an inner surface with advantageous lubricant guiding and retaining properties can be provided for the piston path.

[0052] The iron-based material used to coat the second extensive internal coating is configured as a nanocomposite material.

[0053] Preferably, the first inner coating is produced by a laser cladding process, and the second inner coating is produced by a thermal spraying process during the cooling phase of the first coating, whereby the process heat of the laser cladding process is additionally used during the manufacture of the second coating to increase the adhesion strength of the second coating.

[0054] In some embodiments of this method, a first extensive internal coating is produced via a thermal spraying process, and then a second extensive internal coating is produced via a thermal spraying process. In this case, the first and second coatings partially overlap in the direction of the longitudinal axis, and the second coating is deposited on the roughened first coating. Therefore, a uniform transition with high adhesion strength between the first and second coatings can be achieved along the roughened piston path and between the first and second coatings.

[0055] In some embodiments of this method, additionally or alternatively, the second extensive inner coating is first produced via a thermal spraying process, and then the first extensive inner coating is produced via a laser cladding welding process. In this way, a weld-metallurgical bond with high mechanical strength can be achieved at the transition between the first and second inner coatings. Due to the fact that the first extensive inner coating is fused-metallurgically to the radially adjacent material about the longitudinal axis, significantly improved heat dissipation is also achieved compared to coatings produced via thermal spraying.

[0056] In the last embodiment of the method, the first inner coating and the second inner coating are preferably manufactured in a manner in which the first inner coating and the second inner coating partially overlap in the direction of the longitudinal axis. Therefore, the adhesion strength of the second inner coating can be increased.

[0057] If the first inner coating is constructed in a wavy pattern along the circumference around the longitudinal axis, at least in the area where it overlaps with the second inner coating, further improvement in the adhesion strength of the second inner coating can be ensured. Crack development between the first and second inner coatings can be effectively prevented by avoiding abrupt transitions between them.

[0058] During the fabrication of a first internal coating comprising a hypereutectic aluminum-silicon alloy with at least 12% silicon via laser cladding, it may be desirable to additionally introduce silicon in powder form (e.g., spray) into the welding process. Therefore, the silicon content of the hypereutectic aluminum-silicon alloy can be further increased, for example, to a ratio between 30% and 40%, thereby further increasing the thermal conductivity and wear resistance of the piston path.

[0059] As a preparatory step, all steps of the aforementioned embodiments of the method can be performed after the roughening of the roughened piston path. For example, due to the roughening step, a dovetail profile, known per se, can be fabricated on the surface of the roughened piston path, having multiple undercuts through which the adhesion strength of the coating can be increased.

[0060] Figures 1-8 and Figure 10 Example configurations with various components in relative positioning are shown. If shown as being in direct contact or directly coupled to each other, then in at least one example, such components may be referred to as being in direct contact or directly coupled, respectively. Similarly, components shown as being adjacent or neighboring to each other may be adjacent or neighboring to each other, respectively, in at least one example. As an example, components placed in coplanar contact with each other may be referred to as being in coplanar contact. As another example, components set apart from each other with only space between them and no other components may be so referred to in at least one example. As yet another example, components shown as being above / below each other, on opposite sides of each other, or to the left / right of each other may be so referred to relative to each other. Additionally, as shown in the figures, the topmost component or the highest vertex of a component may be referred to as the “top” of the component in at least one example, and the bottommost component or the lowest point of a component may be referred to as the “bottom” of the component in at least one example. As used herein, top / bottom, upper / lower, above / below may be relative to the vertical axis of the figure and are used to describe the positioning of the components of the figure relative to each other. Therefore, in one example, an element shown above other elements is positioned vertically above the other elements. As yet another example, the shape of an element depicted in the figure can be described as having those shapes (e.g., such as circular, straight, flat, curved, rounded, chamfered, angled, etc.). Additionally, elements shown intersecting each other can be referred to as intersecting elements or intersecting each other in at least one example. Furthermore, an element shown inside or outside another element can be so named in one example. It should be recognized that one or more parts described as “substantially similar and / or identical” differ from each other according to manufacturing tolerances (e.g., within 1%–5% deviation).

[0061] Turn now Figure 1This illustrates an exemplary embodiment of an engine block 10 according to a disclosed internal combustion engine. The engine block 10 can be manufactured from an aluminum alloy (e.g., A226 (EN AC-Al Si9Cu3(Fe))) via a pressure casting process. The engine block 10 is provided as part of a four-cylinder inline internal combustion engine for use in an automobile and has four cylindrical piston paths surrounded by the engine block. Figure 1 The example shows one of the four cylindrical piston paths, piston path 20.

[0062] Piston path 20 is formed by the inner wall of the cylinder bore in engine block 10, and the inner wall of the cylinder bore defines a rough piston path 18 on which a coating can be deposited, as described below. An uncoated piston path may be referred to as a rough piston path 18 for the purpose of distinction below. Figure 1 The piston path 20 in its final state is shown.

[0063] Alternatively, the piston path can also be formed by the inner surface of a cylinder liner made of aluminum alloy, wherein the cylinder liner is set in a pressure casting mold during the manufacture of the engine block.

[0064] The centerline of the cylindrical piston path 20 defines a longitudinal axis 14 along which the piston (not shown) is guided during operation of the engine block 10. A radial direction 16 is arranged transversely to the longitudinal axis 14 of the piston path 20.

[0065] Extensive cooling passages 12, arranged to dissipate process heat generated during the operation of the internal combustion engine, are provided in the engine block 10 at a distance from the cylinder wall in a manner known per se. In one example, the cooling passages 12 are cylinder cooling jackets arranged in the cylinder sidewalls.

[0066] exist Figure 1 In the section 22 shown at the top of the engine block 10 near the top dead center, the piston path 20 has a first internal extensive coating 26, which has a thermal conductivity of 110-120 times that of the radially adjacent material. High thermal conductivity. The first internal extensive coating 26 comprises a hypereutectic aluminum-silicon alloy 54 with a silicon content of approximately 40%, which has a thermal conductivity of 140. Increased tribological properties and high wear resistance.

[0067] The first internal extensive coating 26 extends along the longitudinal axis 14 in a region corresponding to the rotational angle range of the internal combustion engine between 5° and 50° before and after the top dead center position. Additionally or alternatively, the first internal extensive coating 26 is arranged in a region along the longitudinal axis 14 corresponding to the rotational angle range before and after the top dead center position.o and 40 o The first extensive internal coating 26 preferably extends in the region corresponding to the upper 25% and 15% of the piston stroke along the longitudinal axis, within the range of rotational angles of the internal combustion engine. In this region, the maximum process heat is generated during the operation of the internal combustion engine, taking into account the high thermal conductivity and high temperature conductivity of the first extensive internal coating 26. thermal conductivity Specific heat capacity and density The process heat is rapidly dissipated into the cooling channel 12 in the radial direction 16. Furthermore, by applying a first, extensive internal coating 26 to the region generating the maximum process heat, increased manufacturing costs for the engine block 10 can be avoided.

[0068] exist Figure 1 In the section 24 shown at the bottom near the bottom dead center, the piston path 20 has a second internal extensive coating 28, which has a lower thermal conductivity than the radially adjacent material. The second internal extensive coating 28 comprises a nanocomposite material 56 and has approximately 2 The thermal conductivity of the iron-based alloy. Commercially available iron-based alloys for nanocomposite wires (140 MXC, Praxair Surface Technologies) have an iron content between 20% and 50%, and in addition to iron, also contain proportions of chromium, tungsten, niobium, boron, molybdenum, manganese, and carbon. For example, it is possible to... Figure 1 As can be seen by way of example, the second inner extensive coating 28 is adjacent to the first inner extensive coating 26.

[0069] Alternatively, the second extensive internal coating can comprise an iron-based alloy, for example, an iron-carbon alloy having a high porosity of 0.8% carbon. A second extensive internal coating designed in this manner can have approximately 20... Thermal conductivity.

[0070] Prior to coating deposition, the surface of the roughened piston path 18 is roughened in a preparation step. Various methods known to those skilled in the art can be used for this purpose, wherein the roughened piston path 18 can be roughened via etching, grooves, protrusions, etc. Due to the use of such methods, the surface of the roughened piston path 18 can have a so-called dovetail profile in a known manner, which provides the desired premise for high adhesion strength of the coating.

[0071] A first internal extensive coating 26 is extensively deposited on the roughened piston path 18 via a thermal process designed for laser cladding. In this case, an aluminum-silicon alloy in powder form with a silicon content of 12% is used as the cladding material, and simultaneously silicon is sprayed in powder form to increase the silicon content to 40%. As the roughened piston path 18 is melted above the surface at the cladding point, a weld-metallurgical bond with high mechanical strength is formed, and regarding... Figure 4 It was described in more detail.

[0072] A second extensive internal coating 28 is extensively deposited on the roughened piston path 18 via a thermal process configured as a rotating single-wire (RSW) process. In this case, an arc with a current intensity of up to 150 A is ignited between the cathode and a feedable nanocomposite filament of an iron-based alloy serving as the anode, wherein the nanocomposite filament is melted at the location of the arc. A gas introduced into the molten nanocomposite material is deposited on the roughened piston path 18 as a coating material. The deposited second extensive internal coating 28 can have approximately 2 Thermal conductivity.

[0073] Following the deposition of materials for the first extensive inner coating 26 and the second extensive inner coating 28, these materials are partially removed from the coated roughened piston path 18 on the inside for dimensional trimming of the piston path 20. The material removal is performed via a honing tool in multiple honing steps.

[0074] exist Figure 1 In an exemplary embodiment, the layer thickness of the first internal extensive coating 26 and the second internal extensive coating 28 is approximately 250 µm after the piston path 20 is dimensionally trimmed.

[0075] Turn now Figure 3 This illustrates an alternative embodiment of the second inner coating 34, wherein the rough piston path 30 in the segment 24 near the bottom dead center has a parallel offset 32 ​​relative to the segment 22 near the top dead center. Figure 3 The coated roughened piston path 30 is further shown in its state before dimensional trimming. Compared to the first extensive inner coating 26 with a layer thickness of approximately 250 µm, the parallel offset 32 ​​achieves a greater layer thickness of the second inner coating 34 in the radial direction, reaching 750 µm in this particular embodiment, thus enhancing the thermal barrier effect of the second inner coating 34. Therefore, in Figure 3In some examples, the second inner coating 34 may have a thickness greater than that of the first inner extensive coating 26. In one example, the thickness of the second inner coating 34 is twice that of the first inner extensive coating 26. In another example, the thickness of the second inner coating 34 is three times that of the first inner extensive coating 26. Additionally or alternatively, the thickness of the second inner extensive coating 34 may be four times or more than that of the first inner extensive coating 26.

[0076] In use to manufacture according to Figure 2 In a possible embodiment of the disclosed method for the engine block 10, the second internal extensive coating 28 is first manufactured via a rotating monofilament (RSW) process. Then, the first internal extensive coating 26 is manufactured via a laser cladding process. Thus, a weld-metallurgical bond with high mechanical strength is also achieved at the transition between the first internal extensive coating 26 and the second internal extensive coating 28. Figure 2 The coated rough piston path 18 is shown in its state before dimensional trimming. The weld 58 may further correspond to the overlap between the first internal extensive coating 26 and the second internal extensive coating 28.

[0077] In another possible embodiment of the method, the first internal extensive coating 26 is first manufactured via an alternative thermal spraying process designed as a wire-arc spraying process. Subsequently, a second internal extensive coating 28 is also manufactured via a wire-arc spraying process, wherein the first internal extensive coating 26 and the second internal extensive coating 28 partially overlap in the direction of the longitudinal axis 14, and the second internal extensive coating 28 is deposited onto the roughened first internal extensive coating 26. In this way, a uniform transition with high adhesion strength between the first internal extensive coating 26 and the second internal extensive coating 28 is achieved along the roughened piston path 18 and between the first internal extensive coating 26 and the second internal extensive coating 28.

[0078] exist Figure 5 In another embodiment shown, the first inner extensive coating 26 is constructed in a wave-like form along the circumference of the longitudinal axis 14, at least in the region where it overlaps with the second inner extensive coating 28 36. Therefore, an abrupt transition between the first inner extensive coating 26 and the second inner extensive coating 28 can be avoided, and the likelihood of cracks developing between the two coatings is effectively reduced.

[0079] Turn now Figure 6 Its relationship with Figure 2 A schematic diagram showing details of another alternative embodiment of the engine block is illustrated in the same view. For clarity, only the embodiment described is similar to... Figure 2 The differences between the embodiments shown are as follows.

[0080] Compared to the section 22 near the top dead center, the rough piston path 38 of this alternative embodiment of the engine block has a conical recess 44 in the section 24 near the bottom dead center. Figure 6 The coated, roughened piston path 38 is shown in its state before dimensional trimming. After the removal step has been performed for dimensional trimming, the piston path has a constant diameter. The conical recess 44 of the roughened piston path achieves a radial layer thickness of the second inner coating 42 that increases linearly in the downward direction along the longitudinal axis 14 and is manufactured via a stepped offset movement of the RSW device, wherein the stepped offset may include more than five steps, each step representing an increase in the radial layer thickness of the second inner coating 42. The linearly increasing radial layer thickness of the second inner coating 42 in the downward direction results in a downwardly increasing thermal barrier effect along the longitudinal axis 14.

[0081] Turn now Figure 7 Its relationship with Figure 6 The same view shows a schematic diagram detailing yet another alternative embodiment of the engine block. Again, only the embodiment described is similar to... Figure 6 The differences between the embodiments shown are as follows. In this yet another alternative embodiment, the rough piston path 46 in a cold operating state has a conical widening 60 in the section 24 near the bottom dead center, and can be manufactured, for example, by using a shape honing process known per se on the inner wall of the cylinder bore. The transition between the upper cylindrical portion of the rough piston path 46 and the conical widening 60 can be designed as a convex rounding, resulting in a trumpet-shaped shape of the rough piston path 46. In an alternative embodiment, the conical widening may have a slightly concave or slightly convex curved portion in the direction of the longitudinal axis 14.

[0082] Under operating hot conditions, the piston path 48 formed in this manner has a near-perfect cylindrical shape, which reduces frictional losses during piston movement along the longitudinal axis 14 of the piston path 46. After the first and second internal extensive coatings 50 and 52 are removed by shape honing tools to dimensionally trim the piston path 48 in multiple honing steps, the first and second internal extensive coatings 50 and 52 have a constant layer thickness perpendicular to the roughened piston path 46. Figure 7 The piston path 48 is shown in its dimensionally trimmed state. After the first inner coating 50 and the second inner coating 52 are manufactured in a cold operating state, the conical widening 60, which reduces frictional losses during piston movement along the longitudinal axis 14 of the piston path 48, is retained. Simultaneously, this embodiment has the advantage of thermal insulation of the lower section 24 of the piston path as previously described.

[0083] Figure 8An engine system 800 for a vehicle is depicted. The vehicle may be a road vehicle with drive wheels in contact with the road surface. The engine system 800 includes an engine 810, which contains multiple cylinders. Figure 8 A cylinder or combustion chamber is described in detail. Various components of the engine 810 can be controlled by the electronic engine controller 812.

[0084] Engine 810 includes a cylinder block 814 and a cylinder head 816. The cylinder block 814 includes at least one cylinder bore, and the cylinder head 816 includes an intake valve 152 and an exhaust valve 154. In one example, the engine cylinder block 814 may include... Figure 1 The engine block 10. In other examples, where the engine 810 is configured as a two-stroke engine, the cylinder head 816 may include one or more intake and / or exhaust ports. The cylinder block 814 includes a cylinder wall 832, in which a piston 836 is disposed and connected to a crankshaft 840. The cylinder wall 832 may include one or more coatings for adjusting heat transfer from the cylinder wall 832. In one example, the portion of the cylinder wall 832 near the cylinder head 816 includes a first coating having a first thermal conductivity, and the portion of the cylinder wall 832 distal to the cylinder head 816 includes a second coating having a second thermal conductivity, wherein the first coating increases heat dissipation from the cylinder wall 832 relative to the material of the cylinder wall 832, and wherein the second coating increases heat retention within the volume formed by the cylinder wall 832 relative to the material of the cylinder wall 832.

[0085] Therefore, when coupled together, the cylinder head 816 and cylinder block 814 can form one or more combustion chambers. The volume of the combustion chamber 830 is thus adjusted based on the oscillation of the piston 836. The combustion chamber 830 may also be referred to herein as a cylinder. The combustion chamber 830 is shown as communicating with the intake manifold 144 and exhaust manifold 148 via corresponding intake valves 152 and exhaust valves 154. Each intake and exhaust valve can be operated by an intake cam 851 and an exhaust cam 853. Alternatively, one or more of the intake and exhaust valves can be operated by electromechanically controlled valve coils and armature assemblies. The position of the intake cam 851 can be determined by an intake cam sensor 855. The position of the exhaust cam 853 can be determined by an exhaust cam sensor 857. Thus, when the intake valves 152 and 154 are closed, the combustion chamber 830 and cylinder bore can be fluidly sealed, preventing gases from entering or leaving the combustion chamber 830.

[0086] Combustion chamber 830 may be formed by cylinder walls 832, piston 836, and cylinder head 816 of cylinder block 814. Cylinder block 814 may include cylinder walls 832, piston 836, crankshaft 840, etc. Cylinder head 816 may include one or more fuel injectors (such as fuel injector 66), one or more intake valves 152, and one or more exhaust valves (such as exhaust valve 154). Cylinder head 816 may be coupled to cylinder block 814 via fasteners (such as bolts and / or screws). Specifically, when coupled, the cylinder block 814 and cylinder head 816 can be in sealing contact with each other via gaskets, and thus the cylinder block 814 and cylinder head 816 can seal the combustion chamber 830 such that when the intake valve 152 is opened, gas can only flow into the combustion chamber 830 via the intake manifold 144, and / or when the exhaust valve 154 is opened, gas can flow out of the combustion chamber 830 via the exhaust manifold 148. In some examples, only one intake valve and one exhaust valve may be included for each combustion chamber 830. However, in other examples, more than one intake valve and / or more than one exhaust valve may be included in each combustion chamber 830 of the engine 810.

[0087] In some examples, each cylinder of engine 810 may include a spark plug 192 for initiating combustion. In a selected operating mode, in response to a spark advance signal SA from controller 812, ignition system 190 may provide an ignition spark to cylinder block 814 via spark plug 192. However, in some embodiments, spark plug 192 may be omitted, such as in cases where engine 810 can initiate combustion via automatic ignition or fuel injection, as is the case with some diesel engines.

[0088] Fuel injector 866 can be configured to inject fuel directly into combustion chamber 830, a technique known to those skilled in the art as direct injection. Fuel injector 866 delivers liquid fuel in proportion to the pulse width of the signal FPW from controller 812. Fuel is delivered to fuel injector 866 via a fuel system (not shown) including a fuel tank, fuel pump, and fuel rail. Operating current is supplied to fuel injector 866 in response to controller 812 by a driver 868. In some examples, engine 810 may be a gasoline engine, and the fuel tank may include gasoline, which can be injected into combustion chamber 830 via fuel injector 866. However, in other examples, engine 810 may be a diesel engine, and the fuel tank may include diesel fuel, which can be injected into combustion chamber 830 via fuel injector 866. Additionally, in such an example where engine 810 is configured as a diesel engine, engine 810 may include glow plugs to initiate combustion in combustion chamber 830.

[0089] Intake manifold 144 is shown communicating with throttle valve 862, which adjusts the position of throttle plate 864 to control airflow to the engine cylinders. This may include controlling the airflow of compressed air from intake boost chamber 146. In some embodiments, throttle valve 862 may be omitted, and airflow to the engine may be controlled via a single intake system throttle valve (AIS throttle valve) 882, which is coupled to intake passage 842 and located upstream of intake boost chamber 146. In a further example, AIS throttle valve 882 may be omitted, and airflow to the engine may be controlled using throttle valve 862.

[0090] In some embodiments, engine 810 is configured to provide exhaust gas recirculation (EGR) or EGR. When EGR is included, it can be provided as high-pressure EGR and / or low-pressure EGR. In an example where engine 810 includes low-pressure EGR, low-pressure EGR can be provided via EGR passage 135 and EGR valve 138 from a location in the exhaust system downstream of turbine 164 to a location in the engine intake system downstream of intake system (AIS) throttle valve 882 and upstream of compressor 162. EGR can be drawn from the exhaust system into the intake system when a pressure differential of the drive flow exists. The pressure differential can be generated by partially closing AIS throttle valve 882. Throttle plate 884 controls the pressure at compressor 162 inlet. AIS can be electrically controlled, and the position of AIS can be adjusted based on optional position sensor 888.

[0091] Ambient air is drawn into the combustion chamber 830 via an intake passage 842 including an air filter 156. Therefore, air first enters the intake passage 842 through the air filter 156. The compressor 162 then draws air from the intake passage 842 to pass through the compressor outlet pipe (not in...). Figure 1(As shown in the diagram) Compressed air is supplied to the boost chamber 146. In some examples, the intake passage 842 may include an air box (not shown) with a filter. In one example, the compressor 162 may be a turbocharger, wherein power to the compressor 162 is drawn from the exhaust flow via a turbine 164. Specifically, the exhaust can rotate the turbine 164, which is coupled to the compressor 162 via a shaft 161. The wastegate 872 allows the exhaust to bypass the turbine 164, thus allowing control of the boost pressure under varying operating conditions. In response to increased boost demand (such as during operator use of the accelerator pedal), the wastegate 872 may be closed (or its opening may be reduced). By closing the wastegate, the exhaust pressure upstream of the turbine can be increased, thereby increasing the turbine speed and peak power output. This allows for increased boost pressure. Furthermore, when the compressor recirculation valve is partially open, the wastegate can be moved toward the closed position to maintain the desired boost pressure. In another example, in response to a reduced boost demand (such as during operator release of the accelerator pedal), the exhaust valve 872 can be opened (or the exhaust valve opening can be increased). By opening the exhaust valve, the exhaust pressure can be reduced, thereby reducing turbine speed and turbine power. This allows for a reduction in boost pressure.

[0092] However, in an alternative embodiment, compressor 162 may be a mechanical supercharger, wherein power to compressor 162 is drawn from crankshaft 840. Therefore, compressor 162 may be coupled to crankshaft 840 via a mechanical linkage such as a belt. Thus, a portion of the rotational energy output from crankshaft 840 may be transferred to compressor 162 to power compressor 162.

[0093] A compressor recirculation valve 158 (CRV) can be provided in the compressor recirculation path 159 surrounding the compressor 162, thus allowing air to move from the compressor outlet to the compressor inlet to reduce the pressure that can form across the compressor 162. A boost air cooler 157 can be located in the boost chamber 146 downstream of the compressor 162 to cool the boost air supplied to the engine intake manifold. However, in situations such as... Figure 8 In other examples shown, the boost air cooler 157 may be located downstream of the electronic throttle valve 862 in the intake manifold 144. In some examples, the boost air cooler 157 may be an air-to-air boost air cooler. However, in other examples, the boost air cooler 157 may be a liquid-to-air cooler.

[0094] In the depicted example, compressor recirculation path 159 is configured to recirculate cooled compressed air from upstream of booster air cooler 157 to the compressor inlet. In an alternative example, compressor recirculation path 159 may be configured to recirculate compressed air from downstream of the compressor and downstream of booster air cooler 157 to the compressor inlet. CRV 158 can be opened and closed via an electrical signal from controller 812. CRV 158 can be configured as a three-state valve with a default half-open position, and CRV 158 can move from the half-open position to the fully open or fully closed position.

[0095] A universal exhaust oxygen (UEGO) sensor 126 is shown coupled to the exhaust manifold 148 upstream of the emission control device 870. Alternatively, a dual-state exhaust oxygen sensor may replace the UEGO sensor 126. In one example, the emission control device 870 may include multiple catalyst blocks. In another example, multiple emission control devices, each having multiple blocks, may be used. Although the described example shows the UEGO sensor 126 upstream of the turbine 164, it should be recognized that in alternative embodiments, the UEGO sensor may be located downstream of the turbine 164 and upstream of the emission control device 870 in the exhaust manifold. Additionally or alternatively, the emission control device 870 may include a diesel oxidation catalyst (DOC) and / or a diesel cold start catalyst, a particulate filter, a three-way catalytic converter, and a NO₂ filter. x Tracers, selective catalytic reduction devices, and combinations thereof.

[0096] Controller 812 in Figure 8The computer, shown as a microcomputer, includes: a microprocessor unit 102, an input / output port 104, a read-only memory 106, a random access memory 108, a non-fail-to-recover memory (KAM) 110, and a conventional data bus. The controller 812 is shown to receive various signals from sensors coupled to the engine 810, including, in addition to those previously discussed, the following: engine coolant temperature (ECT) from temperature sensor 112 coupled to cooling sleeve 114; position sensor 134 coupled to input device 130 for sensing input device pedal position (PP) adjusted by vehicle operator 132; knock sensor (not shown) for determining exhaust ignition; engine manifold pressure (MAP) measurement from pressure sensor 121 coupled to intake manifold 144; boost pressure measurement from pressure sensor 122 coupled to boost chamber 146; engine position sensor from Hall effect sensor 118 sensing crankshaft 840 position; mass of air entering the engine from sensor 120 (e.g., hot-wire airflow meter); and throttle position measurement from sensor 858. Atmospheric pressure may also be sensed (sensor not shown) for processing by the controller 812. In a preferred aspect of the invention, the Hall effect sensor 118 generates a predetermined number of equally spaced pulses with each rotation of the crankshaft, based on which the engine speed (RPM) can be determined. The input device 130 may include an accelerator pedal and / or a brake pedal. Therefore, the output from the position sensor 134 can be used to determine the position of the accelerator pedal and / or brake pedal of the input device 130, and thus determine the desired engine torque. Therefore, the desired engine torque, as requested by the vehicle operator 132, can be estimated based on the pedal position of the input device 130.

[0097] In some examples, vehicle 805 may be a hybrid vehicle having multiple torque sources available for one or more vehicle wheels 859. In other examples, vehicle 805 may be a conventional vehicle with only an engine, or an electric vehicle with only one or more electric motors. In the example shown, vehicle 805 includes an engine 810 and an electric motor 852. Electric motor 852 may be a motor or a motor / generator. When one or more clutches 856 are engaged, the crankshaft 840 of engine 810 and electric motor 852 are connected to vehicle wheels 859 via transmission 854. In the depicted example, a first clutch 856 is provided between crankshaft 840 and electric motor 852, and a second clutch 856 is provided between electric motor 852 and transmission 854. Controller 812 may send signals to the actuators of each clutch 856 to engage or disengage the clutch, thereby connecting or disconnecting crankshaft 840 from electric motor 852 and its connected components, and / or connecting or disconnecting electric motor 852 from transmission 854 and its connected components. The transmission 854 can be a gearbox, a planetary gear system, or another type of transmission. The powertrain can be configured in various ways, including as a parallel, series, or series-parallel hybrid vehicle.

[0098] The motor 852 receives electrical power from the traction battery 861 to provide torque to the vehicle wheels 859. The motor 852 can also operate as a generator, for example, during braking operation, to provide electrical power to the rechargeable battery 861.

[0099] Turn now Figure 9 The diagram illustrates a method 900 for coating the inner surface of a combustion chamber. More specifically, method 900 describes coating the inner surface of a combustion chamber within an engine cylinder block with respect to the oscillations of a piston disposed therein, adjacent to the combustion chamber.

[0100] Method 900 begins at 902 and includes applying a first coating to the inner surface of the combustion chamber. The first coating may be a coating with high thermal conductivity. In one example, the applied first coating is... Figure 1The first internal extensive coating 26 is substantially identical. Therefore, the applied first coating can be applied to the upper region of the inner surface of the combustion chamber, where the upper region is adjacent to the piston's top dead center (TDC) position. In one example, the upper region is within 5% to 50% of the TDC position in the engine block. Alternatively or additionally, the upper region is within 5% to 40% of the TDC position in the engine block. Alternatively or additionally, the upper region is within 10% to 40% of the TDC position in the engine block. Alternatively or additionally, the upper region is within 15% to 40% of the TDC position in the engine block. Alternatively or additionally, the upper region is within 20% to 40% of the TDC position in the engine block. In one example, the amount of the combustion chamber on which the first coating is applied can be substantially equal to 15% to 25% of the total piston range of motion. In this way, the applied first coating may not be applied to the very top portion of the engine block. The first coating can be applied via one or more of laser cladding and thermal spraying. In some examples, additionally or alternatively, silicon in powder form may be sprayed during the application of the first coating to the engine block, wherein the silicon powder is incorporated into the first coating such that the amount of silicon in the first coating can exceed 20%. In some examples, the amount of silicon is increased to 25% to 50%. In some examples, the amount of silicon is increased to 30% to 40%.

[0101] Method 900 proceeds to 904, which includes applying a second coating while the applied first coating is cooling. The applied second coating may be applied to the remaining uncovered portion of the piston along its oscillating combustion chamber. For example, if the applied first coating is applied to a portion of the combustion chamber surface corresponding to 20% of the total range of piston movement, then the applied second coating may be applied to at least 80% of the total range of piston movement. Additionally or alternatively, the applied first coating and the applied second coating may overlap such that the sum of the portions of the combustion chamber covered by the applied first coating and the second coating is greater than 100%. In one example, the sum may be between 101% and 110%. Additionally or alternatively, the sum may be between 103% and 107%. The applied second coating may be applied via thermal spraying.

[0102] Method 900 proceeds to 906, which includes honing each of the applied first and second coatings. The applied first and second coatings can be honed similarly such that their thicknesses are substantially equal. Additionally or alternatively, the applied first and second coatings can be honed differently such that their thicknesses are unequal. In one example, the applied second coating is honed such that its thickness is greater than that of the applied first coating. Additionally or alternatively, the applied second coating can be honed to include a conical shape, wherein the conical shape may narrow or widen relative to the longitudinal axis of the piston's oscillation.

[0103] Additionally or alternatively, in some embodiments of method 900, the applied first coating may be combined with... Figure 1 The second internal wide-coating 28 is substantially identical to the first coating. The second coating can be applied to the lower region of the combustion chamber via thermal spraying. The second coating can be applied after the application of the first coating (e.g., the second internal wide-coating 28), wherein the applied second coating is similar to... Figure 1 The first internal extensive coating 26 is identical to the first internal extensive coating. The applied second coating (e.g., the first internal extensive coating 26) can be applied via thermal spraying or laser cladding welding. In some examples, if the applied second coating is applied via laser cladding welding, then the applied second coating can be applied in the upper region and over the adjacent portion of the applied first coating, which can result in a weld-metallurgical bond between the two coatings.

[0104] Turn now Figure 10 This illustrates an embodiment 1000 of a combustion chamber 1002 shaped via the surface of an engine block 1004. The combustion chamber 1002 and the engine block 1004 can be respectively coupled to… Figure 8 The combustion chamber 830 and the engine cylinder block 814 are used similarly. More specifically, the engine cylinder block 1004 may form the sidewall of the combustion chamber 1002 (e.g., Figure 8 One or more coatings may be applied to the cylinder wall 832 to adjust the thermal properties of the combustion chamber 1002. The volume of the combustion chamber 1002 may be further defined by the top surface of the piston 1006 and the cylinder head (not shown).

[0105] The first dashed line 1010, the third dashed line 1015, and the second dashed line 1020 illustrate various rotation angle values ​​within the rotation angle range of the piston 1006. The first dashed line 1010 can represent the piston 1006 at 0°. o The rotation angle value, where the first dashed mark 1010 further corresponds to the top dead center position of the piston 1006. The second dashed mark 1020 can represent 180 degrees of rotation of the piston 1006. oThe rotation angle value, where the second dashed mark 1020 further corresponds to the bottom dead center position of the piston 1006. Therefore, in Figure 10 In the example, piston 1006 is at bottom dead center. The third dashed mark 1015 illustrates the midpoint between the first dashed mark 1010 and the second dashed mark 1020, where the third dashed mark 1015 can be equal to 90 degrees of the piston. o Rotation angle value. Therefore, piston 1006 can oscillate around longitudinal axis 1099 from the first dashed mark 1010 to the second dashed mark 1020 and all positions in between.

[0106] First coating (e.g., Figure 1 The first internal extensive coating 26) can be applied from the first dashed mark 1010 at least to a lower threshold 1012. The lower threshold 1012 can be equal to 5 of the piston 1006. o Rotation angle value. Additionally or alternatively, the first coating may be applied from the first dashed mark 1010 to the upper threshold 1013. The upper threshold 1013 may be equal to 50% of the piston 1006. o Rotation angle value. Additionally or alternatively, the first coating may be applied from the first dashed mark 1010 to a position between the lower threshold 1012 and the upper threshold 1013. Furthermore, the first coating may be continuously applied around the perimeter of the inner surface of the combustion chamber 1002, such that the first coating contacts the coolant chambers 1014A and 1014B arranged on both sides of the combustion chamber 1002.

[0107] As shown in the figure, coolant chamber 1014B has a shape different from that of coolant chamber 1014A. In one example, coolant chamber 1014B includes an increased width near the first coating close to top dead center. By doing so, the increased amount of heat dissipation from the upper region of combustion chamber 1002 can be captured by the coolant in the increased-width portion of coolant chamber 1014B to reduce cold start time. Therefore, the increased-width portion of coolant chamber 1014B can extend from the first dashed line marker 1010 to the upper limit threshold 1013.

[0108] Second coating (e.g., Figure 1The second internal extensive coating 28) can extend from an axial position adjacent to the first coating to the second dashed mark 1020. In this way, the second coating can be applied to the remainder of the inner surface of the combustion chamber 1002. In one example, the axial position adjacent to the first coating can be a position where the second coating touches but does not overlap with the first coating. Additionally or alternatively, there can be some overlap between the first and second coatings, such that the second coating is applied over at least the lower portion of the first coating. In some examples, the first coating can extend over the second coating, wherein the thickness of the first coating gradually decreases in the longitudinal direction toward the bottom of the cylinder parallel to the longitudinal axis 1099, such that after a certain distance in the longitudinal direction, the thickness of the first coating is zero, and thereafter only the second coating is applied. In other examples, the second coating can extend over the first coating, wherein the thickness of the second coating gradually decreases in the longitudinal direction toward the top of the cylinder. In some examples, additionally or alternatively, the second coating and / or the first coating can include angled cuts, wherein the angled cuts can be arranged at the position where the first and second coatings meet. In one example, the angled cuts of the first and second coatings can be complementary, such that the transition from the first coating to the second coating is smooth and has a gradual gradient.

[0109] In this way, a portion of the combustion chamber shaped via the engine block can include one or more coatings to enhance the thermal conductivity of different parts of the combustion chamber. The portion of the combustion chamber near the top dead center position of the piston, in which it is arranged to oscillate, can include a first coating with increased thermal conductivity relative to the inner surface of the combustion chamber. The portion of the combustion chamber near the bottom dead center position of the piston can include a second coating with decreased thermal conductivity relative to the inner surface of the combustion chamber. The technical effect of applying the first and second coatings to the combustion chamber is to increase heat transfer in the upper region of the combustion chamber where high heat is generated and to reduce heat transfer in the lower region of the combustion chamber, thereby maintaining lubricant viscosity and the desired engine operating temperature.

[0110] In another representation, an embodiment of an engine block of an internal combustion engine made of aluminum or at least an aluminum alloy includes at least one cylindrical piston path having a longitudinal axis, which, in at least an operating state, is surrounded by the engine block, wherein the piston path has a first extensive internal coating in a section near the top dead center position whose thermal conductivity is higher than that of the radially adjacent material, and a second extensive internal coating in a section near the bottom dead center position whose thermal conductivity is lower than that of the radially adjacent material.

[0111] The first embodiment of the engine block may optionally include the embodiment described above, and further includes, wherein, in a cold operating state, at least one piston path has a conical widening at least in the section near the bottom dead center position.

[0112] A second embodiment of the engine block may optionally include any of the embodiments above, and further includes wherein at least one piston path is formed by the inner wall of a cylinder bore in the engine block or by the inner surface of a cylinder liner.

[0113] A third embodiment of the engine block may optionally include any of the embodiments above, and further includes wherein the first internal coating comprises a hypereutectic aluminum-silicon alloy having at least 12% silicon.

[0114] The fourth embodiment of the engine block may optionally include any of the embodiments above, and further includes wherein the second internal coating comprises an iron-based alloy.

[0115] The fifth embodiment of the engine block may optionally include any of the embodiments above, and further includes, wherein the second internal coating is at least partially formed as an iron-based nanocomposite material.

[0116] The sixth embodiment of the engine block may optionally include any of the embodiments above, further including, wherein the first internal coating extends along the longitudinal axis in a region corresponding to the rotational angle range of the internal combustion engine between 5° and 50°, preferably between 20° and 40°, before and after the top dead center position, wherein the first internal coating thus extends along the longitudinal axis in a region corresponding to the upper 25% and 15% of the piston stroke.

[0117] An embodiment of a method for manufacturing an engine block of any of the above embodiments includes: manufacturing a first internal extensive coating on a rough piston path via a thermal process using an aluminum-silicon alloy having a silicon content of at least 12% as a coating material; manufacturing a second internal extensive coating on the rough piston path via a thermal process using an iron-based material as a coating material; and removing the first and second internal extensive coatings for dimensional trimming of the piston path from the rough piston path.

[0118] A first embodiment of the method may optionally include the embodiments described above, further comprising, wherein a first extensive inner coating is first manufactured via a thermal spraying process, and then a second extensive inner coating is manufactured via a thermal spraying process, wherein the first and second inner coatings partially overlap in the direction of the longitudinal axis, and the second inner coating is deposited on the rough-sprayed first inner coating.

[0119] A second embodiment of the method may optionally include any of the embodiments above, further comprising, wherein the second internal extensive coating is first manufactured via a thermal spraying process, and then the first internal extensive coating is manufactured via a laser cladding process.

[0120] A third embodiment of the method may optionally include any of the embodiments above, further comprising, wherein the first inner coating and the second inner coating are manufactured in such a manner that the first inner coating and the second inner coating partially overlap in the direction of the longitudinal axis.

[0121] A fourth embodiment of the method may optionally include any of the embodiments above, further comprising, wherein the first inner coating is constructed in a wave shape along the circumference about the longitudinal axis, at least in the region overlapping with the second inner coating.

[0122] An embodiment of an engine block includes a first coating and a second coating. The first coating is disposed on the inner surface of the cylinder near the top dead center position of the piston, and the second coating is disposed on the inner surface near the bottom dead center position of the piston. The first coating comprises a hypereutectic aluminum-silicon alloy, and the second coating comprises an iron-based alloy having a lower thermal conductivity than the first coating and the inner surface. A first example of an engine block optionally includes an inner surface comprising aluminum or an aluminum alloy, wherein the thermal conductivity of the inner surface is 110–120 (…). The thermal conductivity of the first coating is 140 ( And the thermal conductivity of the second coating is 2 ( A second example of an engine block may optionally include the first example, further comprising, wherein the silicon content of the first coating is greater than 10%. A third example of an engine block may optionally include the first and / or the second example, further comprising, wherein the second coating comprises a portion having an iron-carbon alloy containing 0.5% to 2% carbon, and wherein the iron-carbon alloy has a thermal conductivity of 20 (…). A fourth example of an engine block may optionally include one or more of the first to third examples, further comprising, wherein the second coating comprises between 20% and 50% iron, and wherein the iron-based alloy further comprises one or more of chromium, tungsten, niobium, boron, molybdenum, manganese, and carbon. A fifth example of an engine block may optionally include one or more of the first to fourth examples, further comprising, wherein the first coating is disposed on the inner surface of the cylinder at the top dead center position and extends to an upper threshold position equal to a 50° rotation angle value of the piston. A sixth example of an engine block may optionally include one or more of the first to fifth examples, further comprising, wherein the second coating is disposed on the inner surface of the cylinder at the bottom dead center position and extends to at least the outermost end of the first coating. A seventh example of an engine block may optionally include one or more of the first to sixth examples, further comprising, wherein the second coating overlaps with the first coating, and wherein the outermost end of the first coating comprises a wavy shape. An eighth example of an engine block may optionally include one or more of the first to seventh examples, further comprising, wherein the second coating includes a conical widening portion, wherein the conical widening portion widens in a direction toward the bottom dead center position. A ninth example of an engine block may optionally include one or more of the first to eighth examples, further comprising, wherein the first coating is disposed on the inner surface via laser cladding, and wherein silicon powder is sprayed during laser cladding, and wherein the first coating comprises between 30% and 40% silicon.

[0123] One embodiment of the system includes: a combustion chamber formed between the surfaces of an engine cylinder head, an engine block, and a piston, the piston being shaped to oscillate along a longitudinal axis passing through its center; a first coating disposed on a surface of the engine block corresponding to the inner surface of the combustion chamber adjacent to the top dead center position of the engine cylinder head and the piston, wherein the first coating has a higher thermal conductivity than the inner surface thermal conductivity, and wherein the first coating is an aluminum-silicon alloy containing more than 12% silicon; and a second coating disposed on a surface of the engine block corresponding to the inner surface of the combustion chamber on the distal side of the engine cylinder head and adjacent to the bottom dead center position of the piston, wherein the second coating has a lower thermal conductivity than the inner surface thermal conductivity, and wherein the second coating is an iron alloy having a nanocomposite material. A first example of the system further includes wherein the first coating has a wavy shape at its distal point where it touches the second coating, and wherein the second coating overlaps with the first coating and completely covers the wavy shape. A second example of the system optionally includes the first example, further comprising, wherein a first coating is disposed on the inner surface of the combustion chamber via laser cladding, and wherein a second coating is disposed on the inner surface of the combustion chamber via thermal spraying after the first coating. A third example of the system optionally includes the first and / or the second example, further comprising, wherein a second coating is disposed on the inner surface of the combustion chamber via thermal spraying, and wherein a first coating is disposed on the inner surface of the combustion chamber via laser cladding after the second coating, and wherein a weld-metallurgical bond is disposed between the overlapping portions of the first and second coatings. A fourth example of the system optionally includes one or more of the first to third examples, further comprising, wherein a first coating is disposed from the top dead center position to a region between a lower threshold and an upper threshold, wherein the lower threshold is equal to a 5° rotation angle of the piston, and wherein the upper threshold is equal to a 50° rotation angle of the piston, and wherein the second coating extends from the outermost end of the first coating to the bottom dead center position, and wherein the second coating touches the outermost end of the first coating.

[0124] An embodiment of one method includes: applying a first coating having a first thermal conductivity to an inner surface of an upper region of a combustion chamber, wherein the first coating is an aluminum-silicon alloy containing greater than or equal to 12% silicon; and during a cooling process of the first coating, applying a second coating having a second thermal conductivity less than the first thermal conductivity to an inner surface of a lower region of the combustion chamber to create a weld-metallurgical bond therebetween, wherein the upper region extends downward from the top of a portion of the combustion chamber formed in an engine block to a portion of the combustion chamber equal to 20% to 40% of its total length, and wherein the lower region extends from the upper region to the bottom of the portion of the combustion chamber formed in the engine block. A first example of the method further includes, wherein applying the first coating comprises laser cladding welding of the first coating. A second example of the method optionally includes the first example, further comprising, wherein silicon powder is sprayed during the application of the first coating to increase the silicon content of the first coating to between 30% and 40%. A third example of the method may optionally include the first and / or second examples, further comprising, wherein the first coating and the second coating are honed to a desired thickness, and wherein the desired thickness of the first coating is less than or equal to 250 µm, and wherein the desired thickness of the second coating is less than or equal to 750 µm. A fourth example of the method may optionally include one or more of the first to third examples, further comprising, wherein the second coating includes a conical widening that increases in width from the upper region to the bottom, and wherein the second coating comprises an iron alloy having a microcrystalline structure, and wherein the first coating comprises an aluminum-silicon alloy.

[0125] Note that the example control and estimation routines included herein can be used with various engine and / or vehicle system configurations. The control methods and routines disclosed herein can be stored as executable instructions in non-transitory memory and can be executed by a control system including a controller in conjunction with various sensors, actuators, and other engine hardware. The specific routines described herein can represent one or more of any number of processing strategies, such as event-driven, interrupt-driven, multitasking, multithreading, etc. Therefore, the various actions, operations, and / or functions described can be executed in the order shown, in parallel, or in some cases omitted. Similarly, this processing order is not necessary to realize the features and advantages of the example embodiments described herein, but is provided for ease of illustration and description. Depending on the specific strategy used, one or more of the described actions, operations, and / or functions can be repeatedly performed. Furthermore, the described actions, operations, and / or functions can be graphically represented as code encoded in a non-transitory memory of a computer-readable storage medium within an engine control system, wherein the described actions are performed by combining instructions in a system including various engine hardware components with an electronic controller.

[0126] It should be recognized that the configurations and routines disclosed herein are exemplary in nature, and these specific embodiments are not to be considered limiting, as many variations are possible. For example, the above-described techniques can be applied to V-6, I-4, I-6, V-12, opposed 4-cylinder, and other engine types. The subject matter of this disclosure includes all novel and non-obvious combinations and sub-combinations of the various systems and constructions and other features, functions, and / or properties disclosed herein.

[0127] As used herein, unless otherwise specified, the term “approximately” is interpreted as the range of average plus or minus five percent.

[0128] The appended claims specifically point to certain combinations and sub-combinations that are considered novel and non-obvious. These claims may relate to a “one” element or a “first” element or its equivalent. These claims should be understood to include combinations of one or more such elements, neither requiring nor excluding two or more such elements. Other combinations and sub-combinations of the disclosed features, functions, elements, and / or characteristics may be claimed by amending existing claims or by filing new claims in this or a related application. These claims, whether broader, narrower, identical, or different from the scope of the original claims, are considered to be included within the subject matter of this disclosure.

Claims

1. An engine block comprising: A first coating and a second coating, wherein the first coating is disposed on the inner surface of the cylinder near the top dead center of the piston, and the second coating is disposed on the inner surface near the bottom dead center of the piston, wherein the first coating comprises a hypereutectic aluminum-silicon alloy having advantageous tribological properties, and the second coating comprises an iron-based alloy having a lower thermal conductivity than the first coating and the inner surface, thereby achieving lower fuel consumption and lower emissions by both improving heat dissipation in the upper region of the piston path and providing thermal insulation in the lower region of the piston path.

2. The engine block according to claim 1, wherein the inner surface comprises aluminum or an aluminum alloy, and wherein the thermal conductivity of the inner surface is less than that of the first coating and greater than that of the second coating.

3. The engine block according to claim 1, wherein the silicon content of the first coating is greater than 10%.

4. The engine block of claim 1, wherein the second coating comprises a portion having an iron-carbon alloy, the iron-carbon alloy comprising between 0.5% and 2% carbon.

5. The engine block of claim 1, wherein the second coating comprises between 20% and 50% iron, and wherein the iron-based alloy further comprises one or more of chromium, tungsten, niobium, boron, molybdenum, manganese, and carbon.

6. The engine block of claim 1, wherein the first coating is disposed on the inner surface of the cylinder at the top dead center position, and the first coating extends to a point equal to 50° of the piston. o The upper limit threshold position of the rotation angle value.

7. The engine block of claim 6, wherein the second coating is disposed on the inner surface of the cylinder at the bottom dead center position, and the second coating extends to at least the far end of the first coating.

8. The engine block of claim 1, wherein the second coating overlaps with the first coating, and wherein the outermost end of the first coating comprises a wavy shape.

9. The engine block of claim 1, wherein the second coating comprises a conical widening portion, wherein the conical widening portion widens in a direction toward the bottom dead center position.

10. The engine block of claim 1, wherein the first coating is disposed on the inner surface via laser cladding, and wherein silicon powder is sprayed during the laser cladding, and wherein the first coating comprises between 30% and 40% silicon.

11. A system for an engine, comprising: A combustion chamber is formed between the surfaces of an engine cylinder head, an engine block, and a piston, the piston being shaped to oscillate along a longitudinal axis passing through its center. A first coating is disposed on the surface of the engine block corresponding to the inner surface of the combustion chamber adjacent to the top dead center position of the engine cylinder head and the piston, wherein the first coating has a higher thermal conductivity than the inner surface thermal conductivity, and wherein the first coating is an aluminum-silicon alloy containing more than 12% silicon, and the first coating has advantageous tribological properties. as well as A second coating is disposed on the surface of the engine block corresponding to the inner surface of the combustion chamber at the position of the piston's bottom dead center on the far side of the engine cylinder head, and wherein the thermal conductivity of the second coating is lower than that of the inner surface, and wherein the second coating is an iron alloy having nanocomposite materials. Lower fuel consumption and lower emissions are achieved by improving heat dissipation in the upper region of the piston path and providing thermal insulation in the lower region of the piston path.

12. The system of claim 11, wherein the first coating comprises a wave-like shape at the point where the first coating touches the far end of the second coating, and wherein the second coating overlaps with the first coating and completely covers the wave-like shape.

13. The system of claim 11, wherein the first coating is disposed on the inner surface of the combustion chamber via laser cladding, and wherein the second coating is disposed on the inner surface of the combustion chamber via thermal spraying after the first coating.

14. The system of claim 11, wherein the second coating is applied to the inner surface of the combustion chamber via thermal spraying, and wherein the first coating is applied to the inner surface of the combustion chamber via laser cladding after the second coating, and wherein a weld-metallurgical bond is provided between the overlapping portions of the first and second coatings.

15. The system of claim 11, wherein the first coating is disposed from the top dead center position into a region between a lower threshold and an upper threshold, wherein the lower threshold is equal to 5% of the piston. o The rotation angle value, wherein the upper limit threshold is equal to 50 degrees of the piston. o The rotation angle value, wherein the second coating extends from the far end of the first coating to the lower stop position, and wherein the second coating touches the far end of the first coating.

16. A method for an engine, comprising: A first coating having a first thermal conductivity is applied to the inner surface of the upper region of the combustion chamber, wherein the first coating is an aluminum-silicon alloy containing greater than or equal to 12% silicon, and the first coating has favorable tribological properties. as well as During the cooling process of the first coating, a second coating having a second thermal conductivity lower than the first thermal conductivity is applied to the inner surface of the lower region of the combustion chamber to create a weld-metallurgical bond between the first coating and the second coating. in The upper region extends downward from the top of a portion of the combustion chamber formed in the engine block to a portion of the combustion chamber equal to 20% to 40% of the total length of the combustion chamber, and the lower region extends from the upper region to the bottom of a portion of the combustion chamber formed in the engine block, thereby achieving lower fuel consumption and lower emissions by both improving heat dissipation in the upper region of the piston path and providing thermal insulation in the lower region of the piston path.

17. The method of claim 16, wherein applying the first coating comprises laser cladding welding of the first coating.

18. The method of claim 17, further comprising spraying silicon powder during the application of the first coating to increase the silicon content of the first coating to between 30% and 40%.

19. The method of claim 16, further comprising honing the first coating and the second coating to a desired thickness, wherein the desired thickness of the first coating is less than or equal to 250 µm, and wherein the desired thickness of the second coating is less than or equal to 750 µm.

20. The method of claim 19, wherein the second coating comprises a conical widening that increases in width from the upper region to the bottom, and wherein the second coating comprises an iron alloy having a microcrystalline structure, and wherein the first coating comprises an aluminum-silicon alloy.

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