Surface treatment of a metal surface of a metal component, such as a glass manufacturing

Abstract

The present disclosure relates to a surface treatment method for treating a molding surface (2) of a glass manufacturing mold (1). The surface treatment method comprises the step of cold spraying a solid metal powder (4) onto a molding surface (2) of a glass manufacturing mold (1) to obtain a solid deposit (5). It further comprises a step of machining the solid deposit (5) to obtain the coating. The disclosure also relates to a metal powder, a surface treatment machine and a surface treatment apparatus for implementing such a method, and a glass manufacturing mold obtained by such a method.

Description

Technical Field

[0001] This application generally relates to metal castings in the glass manufacturing field, particularly molds made of cast iron, brass, bronze (and other alloys containing copper and tin) or steel, used to manufacture glass objects, such as bottles or any metal parts that may typically come into contact with the preform.

[0002] This application relates more particularly to the surface treatment of the metal surfaces of these metal parts that come into contact with the glass preform (or droplet) during the manufacture of glass objects. It finds specific, but not limiting, applications in the surface treatment of molded surfaces of molds to improve the thermal and / or mechanical properties of the mold during the roughing and finishing stages. Background Technology

[0003] The manufacture of glass objects, especially insulated glass such as bottles, involves several steps.

[0004] During the first step, known as the roughing step, viscous glass is fused together (at temperatures between 700°C and 1200°C), poured out as a preform (drop), and then introduced into a die (known as a roughing die) via a deflector and dispensing channel. The viscous glass undergoes compression in the roughing die and is then perforated to bring it into contact with the die wall and obtain a billet. The billet is then subjected to temperatures up to 900°C, depending on the area and thickness of the billet.

[0005] Then, during a second step called finishing, the resulting preform is transferred to a finishing mold for blow molding to give it its final shape. During the contact between the preform and the finishing mold, a sharp drop in temperature occurs, along with elongation of the glass. The final product is obtained after this blow molding step. It is then heated to approximately 600°C.

[0006] Glass manufacturing molds therefore have several functions.

[0007] First, glass-making molds possess a thermal function by allowing the glass to cool. In practice, the preform must be sufficiently cooled to retain its shape upon exiting the roughing die. For this, the preform must be held in the roughing die for a sufficient time to allow a certain amount of heat to dissipate, thus allowing the glass to reach the desired viscosity. It is readily understood that this heat increases with the weight of the preform, and at a constant thermal conductivity, the weight of the preform typically results in a longer residence time in the roughing die. Furthermore, during the finishing steps, the molding surface of the die is heated via heat transfer between the core of the preform and its surface. To avoid excessively long cooling times in the roughing die that are incompatible with industrial production rates, and excessively high surface temperatures in the finishing die that would alter the die structure, the die material must be carefully selected to possess sufficient thermal conductivity.

[0008] For large objects, such as sparkling wine and champagne bottles, copper and tin alloy molds, especially bronze molds, have been proposed due to their good thermal conductivity. However, these molds are very expensive.

[0009] Therefore, there is a desire for glass manufacturing molds that exhibit good thermal conductivity while being cheaper than copper and tin alloy molds.

[0010] Secondly, glass manufacturing molds serve a geometrical function, as they impart the final shape of the finished product. However, this function is compromised by mold wear. These molds, typically made of cast iron, bronze (and other alloys containing copper and tin), or steel (especially carbon steel, stainless steel, and heat-resistant steel), tend to wear rapidly due to abrasion and / or corrosion caused by the presence of silica in the glass, particularly in areas such as the mold's mating planes (or seams), bottom, rings, or neck. To avoid the need to replace the entire mold, techniques have been proposed for refilling with a welding torch, plasma-transferred arc (PTA), or laser, during which a layer of metallic alloy is fused to the mold surface at the edges. The resulting mold is then machined after cooling to achieve the desired geometry.

[0011] However, known surface treatment techniques are not entirely satisfactory because they allow for treatment only of the edges rather than the entire molding surface. In fact, treating the entire molding surface with these known techniques poses a high risk of mold breakage. Therefore, known surface treatment techniques cannot completely prevent mold wear, necessitating periodic mold replacement.

[0012] Therefore, it is desirable to have new surface treatment technologies available to treat the entire molded surface. Summary of the Invention

[0013] One objective of this application is to at least partially remedy the aforementioned shortcomings.

[0014] Therefore, according to a first aspect, the present invention provides a method for surface treatment to treat the metal surface of a metal part configured to contact a preform, such as the molding surface of a glass manufacturing mold, the surface treatment method comprising the following steps:

[0015] - Cold spraying solid metal powder onto a metal surface to obtain a solid deposit; and

[0016] - The solid deposit is mechanically processed to obtain a coating.

[0017] Some preferred but non-limiting features of the surface treatment method according to the first aspect are as follows, used individually or in combination:

[0018] - Use spraying gas that has been subjected to a pressure greater than 30 bar, such as between 40 bar and 70 bar, such as about 50 bar, to spray metal powder;

[0019] - Use spraying gas heated to a temperature greater than or equal to 750°C, especially greater than or equal to 800°C, for example including temperatures between 900°C and 1150°C to spray metal powder;

[0020] - During the spraying step, the spraying distance corresponding to the distance between the nozzle used for spraying metal powder and the metal surface includes between 15 mm and 60 mm, preferably between 15 mm and 35 mm, for example equal to about 20 mm or about 30 mm;

[0021] - During the spraying step, the travel speed of the nozzle used to spray the metal powder during spraying includes between 200 mm / s and 1000 mm / s, for example, between 200 mm / s and 450 mm / s;

[0022] - The spraying process is carried out for a sufficient amount of time to obtain a solid deposit with a thickness of 0.3 mm to 3 mm, preferably 0.5 mm to 2.5 mm;

[0023] - The injection flow rate of the metal powder into the spraying gas is 1 to 10 cm³. 3 / min, preferably 2 to 3cm 3 / min, for example, about 2.5 cm 3 / min;

[0024] - The coating has better mechanical strength than the metal surface, especially better wear resistance;

[0025] - The coating has a higher thermal conductivity than the metal surface;

[0026] -The metal powder is essentially composed of NiCr powder; and / or

[0027] -Based on the mass relative to the total mass of the powder, metal powder is essentially composed of the following:

[0028] • 60-70%, preferably 62-68% copper;

[0029] •7-17%, preferably 10-15% nickel;

[0030] • 5-15%, preferably 8-12% aluminum;

[0031] • 5-15%, preferably 8-12% zinc

[0032] It should be understood that the sum of the components equals 100%.

[0033] According to the second aspect, a metal component, such as a glass manufacturing mold, is proposed, comprising:

[0034] - A metal surface, said metal surface being configured as a contact blank; and

[0035] - A coating that covers all or part of a metal surface and comprises a metal alloy, said metal alloy being obtained by cold spraying metal powder onto the metal surface according to the surface treatment method of the first aspect.

[0036] Some preferred, but non-limiting, features of the metal component according to the second aspect are as follows, individually or in combination:

[0037] - The metal surface includes at least one of the following materials: graphite cast iron having a layered, worm-like or spherical microstructure, copper and tin based alloys such as bronze, carbon steel, fire-resistant steel or stainless steel, or brass;

[0038] -The metal powder is essentially composed of nickel and chromium;

[0039] - The coating is obtained by cold spraying a metal powder consisting essentially of NiCr powder or, by mass, a metal powder consisting essentially of the following:

[0040] • 60-70%, preferably 62-68% copper;

[0041] •7-17%, preferably 10-15% nickel;

[0042] • 5-15%, preferably 8-12% aluminum; and

[0043] •5-15%, preferably 8-12% zinc;

[0044] It should be understood that the sum of the components equals 100%;

[0045] - The component includes a glass manufacturing mold, a metal surface corresponding to the molding surface of the glass manufacturing mold, and includes at least one of the following materials: graphite cast iron, carbon steel, fire-resistant steel, or stainless steel having a layered, worm-like, or spherical microstructure.

[0046] According to the third aspect, a device includes:

[0047] - A machine for surface treatment of glass manufacturing molds, comprising:

[0048] - A support member configured to receive a metal component, such as a glass manufacturing mold, the metal component having a metal surface configured to contact a preform; and

[0049] - A nozzle configured to cold-spray the solid metal powder onto the metal surface to form a solid deposit, and

[0050] - A processing station configured to process the solid deposit and obtain a coating. Attached Figure Description

[0051] Other features, purposes, and advantages will become apparent from the following description, which is purely illustrative and not restrictive, and is given with reference to the accompanying drawings, wherein:

[0052] Figure 1 An example of an apparatus for metal surface treatment of metal parts according to one embodiment is shown schematically;

[0053] Figure 2 This is a flowchart illustrating the steps of a surface treatment method for a surface of a metal component according to one embodiment; and

[0054] Figure 3 It is a schematic cross-sectional view of a glass manufacturing mold, which includes a coating according to one embodiment.

[0055] In all the accompanying drawings, similar elements have the same reference numerals. Detailed Implementation

[0056] The present disclosure will be described in more detail below with regard to the surface treatment of the molding surface 2 of the glass manufacturing mold 1. However, this is not limiting; the present disclosure applies to the surface treatment of any metal surface of a metal component configured to contact the preform.

[0057] refer to Figure 1 This application relates to the surface treatment of all or part of the molding surface 2 of a glass manufacturing mold 1. The glass manufacturing mold 1 may specifically include a roughing die 1 configured to receive glass droplets (preforms) and form blanks. The molding surface 2 corresponds to the surface of the mold 1 that may come into contact with the preform during the forming process. The molding surface 2 may specifically include at least one of the following materials: graphite cast iron having a layered, worm-like, or spherical microstructure; bronze (and other alloys including copper and tin); carbon steel; fire-resistant steel or stainless steel; or brass. Preferably, the glass manufacturing mold 1 is integrally formed from the same constituent material as the molding surface 2.

[0058] To process the molding surface 2 of the glass manufacturing mold 1, it is proposed to spray cold metal powder 4 onto all or part of the molding surface 2 by means of spraying gas 3 under high pressure.

[0059] Cold spraying under high pressure allows for a deposit density very close to the theoretical density of the solid metal material constituting the powder without heating the molding surface 2 during deposition, thus avoiding changes to the metallurgical quality of the molding surface 2 and the solid deposit 5. Furthermore, it enables the achievement of high deposition thicknesses (up to several millimeters) with low roughness and material efficiency greater than 90%, as well as high interparticle cohesion. Moreover, this cold spraying method eliminates the need for prior steps of preparing the molding surface 2 or masking the mold 1 to be treated.

[0060] Surface treatment equipment 9

[0061] Figure 1 The image shows an apparatus 9 for such surface treatment of all or part of the molding surface 2 of a glass manufacturing mold 1. The apparatus 9 includes a surface treatment machine 10 and a processing station 11.

[0062] The surface treatment machine 10 is configured to cold spray metal powder 4 in solid form onto the molding surface 2 of the mold 1. For this purpose, it includes a nozzle 7, preferably made of ceramic, comprising:

[0063] - A system for heating and pressurizing the spray gas 3 (typically nitrogen or helium) in the pressurization chamber 12;

[0064] - Powder dispenser 13, for supplying metal powder 4;

[0065] - Injection system 18, for injecting metal powder 4 into spray gas 3 downstream of pressurized chamber 12 so that it is not heated by surface treatment machine 10 and thus remains solid;

[0066] - Delivery system 19 for conveying metal powder 4 from powder dispenser 13 to injection system 18 by means of carrier gas (usually the same as spraying gas 3);

[0067] - A convergent-divergent nozzle 8, positioned downstream of the injection system 18 and configured to accelerate the spray gas 3 as it delivers the metal powder 4, the divergent portion of the nozzle 8 forming a deposition tube 14; and

[0068] - Cooling system 15, which may include conduits surrounding the deposition tube 14 to cool the spraying gas 3 that carries the metal powder 4 by means of conducting cooling fluid around the deposition tube 14; the cooling fluid may particularly include distilled water at a temperature lower than that of the spraying gas 3, typically at a temperature of 8 to 20°C.

[0069] The outlet diameter of nozzle 7 (at the free end of deposition tube 14) is between 2 mm and 10 mm, for example, about 6 mm.

[0070] The surface treatment machine 10 also includes a support 17 and actuators (not shown). The support 17 is configured to fix the glass manufacturing mold 1 relative to the nozzle, and the actuators (not shown) are configured to move the nozzle 7 relative to the molding surface 2 in all three spatial directions. These actuators can move the nozzle 7, the support 17 on which the mold 1 is mounted, or both the nozzle 7 and the support 17. The actuators are configured to move the nozzle 7 relative to the molding surface 2 at a speed between 200 mm / s and 1000 mm / s. Preferably, to limit premature wear of the equipment, particularly premature wear of the injection head, the sweeping speed is included between 200 mm / s and 450 mm / s (within 5%). The actuators are also configured to displace the impact zone by a distance between 0.5 mm and 2.5 mm (without sweeping between two adjacent beads), for example, about 1 mm or 2 mm (within 10%).

[0071] The heating system is configured to heat the spray gas 3 to a temperature greater than or equal to 750°C, particularly greater than or equal to 800°C, for example, between 900°C and 1150°C. The spray gas 3 is also pressurized in a pressurization chamber to a pressure greater than or equal to 35 bar, preferably between 40 bar and 70 bar, for example, about 50 bar.

[0072] The nozzle 7 can be controlled by a remote control station 16 placed near the surface treatment machine 10 or at a certain distance.

[0073] The processing station 11 includes a support and processing tools. The support is configured to receive a mold 1 coated with a solid deposit 5. The processing tools, such as a milling machine, are configured to process the solid deposit 5 and obtain a coating 6. The processing tools can be operated by an operator or mounted on the equipment 8 and controlled by a remote control station, such as the same control station 16 for the nozzle 7.

[0074] Surface treatment method 100

[0075] exist Figure 2 The image shows a method 100 for surface treatment of a molded surface 2, implemented by a surface treatment apparatus 9. It includes the following steps:

[0076] - Solid metal powder 4 is cold-sprayed 110 onto the molding surface 2 of a glass manufacturing mold 1 to obtain a solid deposit 5; and

[0077] - Machining 120 solid deposits 5 to obtain a coating 6 ( Figure 3 ).

[0078] Method 100 can be applied to the entire molding surface 2 of the mold 1 or only to a portion of the surface 2.

[0079] During spraying step 110, a spraying gas 3 at high temperature (typically nitrogen or helium) and high pressure propels metal powder 4 onto the molding surface 2 at supersonic speeds (greater than 300 m / s) to generate a solid deposit 5 intended to form a coating 6 through the impact of the metal powder 4 on the molding surface 2. This impact ensures the quality of the deposit. In this application, the deposit is referred to as "solid" in relation to the fact that the particles of the metal powder 4 remain solid throughout the spraying and adhesion to the molding surface 2 step 110. This is in contrast to methods where the temperature of the metal powder 4 exceeds its melting point, causing all or part of the powder 4 to melt at a certain point during the process. When the metal powder 4 comes into contact with the molding surface 2 at high speed, it mechanically adheres to the molding surface 2 through plastic deformation with strong adhesion, which allows for the avoidance of high-temperature-related defects such as oxidation, residual stress, phase transformation, etc. The solid deposit 5 then becomes integral with the molding surface 2; that is, it can only be separated from the molding surface 2 by complete or partial decomposition.

[0080] The spraying step 110 is referred to as cold because the metal powder 4 is not heated before or during deposition, except through its contact with the spraying gas 3 or the molding surface 2.

[0081] During spraying step 110, the spraying gas 3 is heated and pressurized to ensure that the metal powder 4 is sprayed at a spraying speed (the speed of the metal powder 4 at the exit of the nozzle 7) that allows the metal powder 4 to plastically deform during its impact contact with the surface. It should be noted that the gas is heated and pressurized before injecting the solid powder into the gas and spraying it onto the molded surface 2 to ensure that the metal powder 4 remains solid. For this purpose, the spraying speed is greater than or equal to the critical speed of the metal powder 4. This critical speed corresponds to the speed at which the solid deposit 5 may adhere: when the impact speed is below the material's critical speed, the metal powder particles 4 will not plastically deform and may bounce and / or erode the molded surface 2. The critical speed depends on the properties of the material and the particle size of the metal powder 4. The critical speed is, for example, higher than 1250 m / s in the case of metal powder 4 containing hard materials (such as titanium dioxide-based materials) than in the case of metal powder 4 containing ductile materials (such as copper-based materials) (approximately 600 m / s). The formula E1 for determining the critical velocity of a material has been confirmed by T. Schmidt, F. Gärtner, H. Assadi and H. Kreye, “Development of a generalized parameter window for cold spray deposition”, Acta Mater. 54(2006)729-742; https: / / doi.org / 10.1016 / j.actamat.2005.10.005.

[0082] (E1)

[0083] Where: σ u It is the fracture stress of the material;

[0084] ρ is the density of the material to be characterized;

[0085] T I It is the initial temperature of the material to be characterized;

[0086] T m It is the melting point of the material to be characterized;

[0087] C p It is specific heat;

[0088] T r It is a reference temperature equal to 293K; and

[0089] F1 and F2 are calibration coefficients used to recalibrate the calculated values ​​to the measured speed values.

[0090] Therefore, the pressure applied to the spraying gas 3 is selected to exceed the critical velocity of the metal powder 4 used for the solid deposit 5. A pressure greater than or equal to 35 bar, preferably greater than or equal to 40 bar, and for example equal to 50 bar, is suitable for most metal powders that can be used for surface treatment of glass manufacturing molds.

[0091] Furthermore, the spraying gas 3 is heated to a temperature generally greater than or equal to 750°C, particularly greater than or equal to 800°C, for example, between 900°C and 1150°C. This heating temperature is advantageously at least 300°C lower than the melting point of the components of the metal powder 4, which has the lowest melting point, and is, for example, between 300°C and 700°C lower than that melting point.

[0092] Where applicable, the spraying gas 3 can also be accelerated by modifying the construction of the nozzle 7 (such as by modifying the gas channel cross-section, for example in a convergent-divergent nozzle 8).

[0093] For the nickel-chromium based powder described below, the critical velocity is, for example, about 574 m / s.

[0094] Where applicable, the spraying gas 3 can be cooled downstream of the point where the metal powder 4 is injected into the gas to ensure that the metal powder 4 remains solid without reducing the spraying speed of the powder.

[0095] A spraying step 110 is performed to obtain a solid deposit 5, the thickness of which is sufficient to allow machining of the solid deposit 5 to obtain a coating 6. This thickness of the solid deposit 5 typically includes between 0.3 mm and 3 mm, preferably between 0.5 mm and 2.5 mm. Therefore, the thickness of the coating 6 (after machining) can include between 0.1 mm and 1.5 mm.

[0096] For this purpose, the molding surface 2 moves relative to the surface treatment machine 10 during the spraying step 110 to allow deposition on all or part of the molding surface 2. The nozzle 7 may move while the glass manufacturing mold 1 is stationary, or in a variation, the glass manufacturing mold 1 may move while the nozzle 7 is stationary, or both the nozzle 7 and the glass manufacturing mold 1 may move. The relative travel speed and number of passes on a given surface determine the thickness of the deposit. For example, the relative travel speed between the nozzle 7 and the molding surface 2 of the glass manufacturing mold 1 may range from 200 mm / s to 1000 mm / s, such as from about 200 mm / s to 450 mm / s (up to 5%).

[0097] The flow rate of the distributor 13 to the metal powder 4 includes 1 cm 3 / min and 10cm 3 Between / min, preferably within 2cm 3 / min and 3cm 3 Between / min, for example, about 2.5 cm 3 The metal powder 4 supplied in this way is entirely conveyed to the injection system 18 via the carrier gas, such that this conveying flow rate also constitutes the flow rate through which the metal powder 4 is injected into the spraying gas 3 via the injection system 18. For this purpose, the carrier gas flow rate is typically between 2.0 cubic meters per hour and 6.0 cubic meters per hour (m³ / min). 3 Between / h), for example, approximately 4.0 cubic meters per hour or 4.5 cubic meters per hour (m 3 / h).

[0098] The size of the solid deposit 5 (the width of the bead) is preferably between 0.5 mm and 2 mm, for example, about 1 mm (within 10%). This size depends on the distance between the outlet of the nozzle 7 of the surface treatment machine 10 and the molding surface 2, and on the outlet diameter of the nozzle 7. To obtain the aforementioned solid deposit size, the distance is typically between 15 mm and 60 mm, preferably between 15 mm and 35 mm, for example, equal to about 20 mm or about 30 mm, and the outlet diameter of the nozzle 7 is between 2 mm and 10 mm, for example, about 6 mm.

[0099] The sweep spacing (the distance between the centers of two adjacent solid sediment beads 5) includes a range of 0.5 mm and 2 mm, for example, about 1 mm (within 10%). It is preferably substantially equal to the size of the solid sediment 5.

[0100] Metal powder 4

[0101] The metal powder 4 preferably contains 75% by mass or more, advantageously at least 80% by mass, spherical particles relative to the total mass of the powder.

[0102] Laser particle size distribution was measured according to ISO 13320:2019.

[0103] The diameter of the powder particles is advantageously between 10 and 50 μm, particularly between 12 and 45 μm, and preferably has a D50 value between 20 and 30 μm.

[0104] The melting point of the powder compound is typically higher than the temperature of the preform (which can reach 1100°C) to avoid thermal degradation of the coating 6 during molding. Preferably, the melting point of the powder component with the lowest melting point is 300°C higher than the preform temperature.

[0105] “ Bulk density The evaluation was conducted according to NF EN ISO 3923 (2018) concerning "Metallic Powders - Determination of Apparent Density After Packing". Typically, a volume of 25 cm³ is used. 3 The sample was prepared using a KERN SEAL balance with a maximum capacity of 6000g and a resolution of 0.1g. Filling was stopped after 3000 strokes.

[0106] “ True density The evaluation was conducted according to NF EN ISO 8130-2 (2011) "Coating powders - Determination of density by gas comparison pycnometer (reference method)". A 10cm... 3 A small helium specific gravity flask (Konta UPYC 1200E). The powder mass was measured using a balance, for example, a METTLER TOLEDO AB104 with a maximum weighing capacity of 110 g and a resolution of 0.1 mg.

[0107] The bulk density of metal powders is typically 3 to 7 g / cm³. 3 between.

[0108] The actual density is usually 6-10 g / cm³ 3 Ideally, the density should have a small standard deviation, such as 0.001. Metal powders with this true density allow for the acquisition of denser solid deposits.

[0109] Within the meaning of this disclosure, when the powder contains at least 98% by mass, preferably at least 99% by mass of compound A relative to the total mass of the powder, the powder is considered "..." Basically by Compound A composition ".

[0110] Metal powder containing NiCr alloy

[0111] According to the first embodiment, the metal powder 4 is essentially composed of an alloy of nickel and chromium (referred to as a nickel-chromium alloy and denoted as NiCr). By essentially being composed of…, it will be understood here that at least 98% by mass of the NiCr powder consists of an alloy of nickel and chromium, with the remainder possibly containing at most 2% by mass of another component. Preferably, the matrix powder contains at least 99% by mass of NiCr. Other components may include, for example, at least one of the following elements: carbon, silicon, manganese, oxygen, and nitrogen. This makes it possible to obtain a coating 6 containing NiCr, which imparts thermomechanical protection to the mold 1. In particular, the NiCr-containing coating 6 imparts better wear resistance to the mold 1, which is especially useful in the case of molds made of borosilicate glass and in the case of molds made of copper and tin alloys. Borosilicate glass is particularly abrasive and often causes premature wear of the mold. Copper and tin alloy molds have good thermal conductivity and are often very expensive, so it is advantageous to exchange some of the thermal conductivity of the mold to allow it to last longer.

[0112] Therefore, according to an advantageous variation of the first embodiment, the glass manufacturing mold 1 is a mold for borosilicate glass or a mold made of a copper and tin alloy (e.g., bronze).

[0113] The nickel content in the NiCr alloy is advantageously included between 40% by mass and 85% by mass, preferably between 45% by mass and 80% by mass, relative to the total mass of the NiCr alloy, with the balance consisting essentially of chromium.

[0114] According to the first variant, the nickel content in the NiCr alloy is 40% to 50% by mass relative to the total mass of the NiCr alloy, while the chromium content is 50% to 60% by mass (i.e., the margin required to achieve essentially 100% NiCr alloy mass). For example, the nickel content in the NiCr alloy is essentially equal to 50% by mass relative to the total mass of the NiCr alloy, while the chromium content is essentially equal to 50% by mass (i.e., the margin required to achieve essentially 100% NiCr alloy mass). According to the second variant, the nickel content in the NiCr alloy is approximately 80% by mass relative to the total mass of the NiCr alloy, while the chromium content is approximately 20% by mass (i.e., the margin required to achieve essentially 100% NiCr alloy mass).

[0115] The particle size of NiCr powder is advantageously included between 10 and 50 μm. The D50 value of NiCr powder is typically included between 20 and 30 μm, preferably between 25 and 27 μm, for example, substantially equal to 26.1 μm. The D10 value of NiCr powder is typically included between 10 and 20 μm, preferably between 14 and 16 μm, for example, substantially equal to 14.7 μm. The D90 value of NiCr powder is typically included between 40 and 50 μm, preferably between 43 and 45 μm, for example, substantially equal to 44.0 μm.

[0116] The bulk density of NiCr powder is typically 4 to 5 g / cm³. 3 Especially 4.3 to 4.8 g / cm³ 3 For example, approximately 4.7 g / cm³ 3 The actual density of NiCr powder is typically 7.5 to 8.5 g / cm³. 3 Especially 7.6 to 8.0 g / cm 3 For example, approximately 7.71 g / cm³ 3 .

[0117] Metal powder containing cupronickel alloy

[0118] According to the second embodiment, the metal powder 4 comprises an alloy of copper, nickel, aluminum, and zinc, or essentially an alloy of copper, nickel, aluminum, and zinc, referred to hereinafter as "white copper" or CuNiAlZn for simplicity. This allows for the preparation of a coating 6 comprising a so-called white copper alloy, which imparts better thermal conductivity to the mold, enabling more uniform cooling of the glass upon contact with the coated mold. This coating is particularly advantageous in the case of molds used for soda-lime glass.

[0119] Therefore, according to an advantageous variation of this first embodiment, the glass manufacturing mold 1 is a mold for soda-lime glass. The material of the mold 1 is typically cast iron, such as graphite cast iron with a layered, worm-like, or spherical microstructure, carbon steel, fire-resistant steel, or stainless steel.

[0120] According to this second embodiment, the metal powder 4 is essentially composed of an alloy powder, which comprises, by mass, the following relative to the total mass of the alloy:

[0121] • 60-70%, preferably 62-68% copper;

[0122] • 7-17%, preferably 10-15% nickel;

[0123] • 5-15%, preferably 8-12% aluminum;

[0124] • 5-15%, preferably 8-12% zinc; and

[0125] • Any balance is preferably composed essentially of chromium, manganese and / or iron;

[0126] It should be understood that the sum of the components equals 100%.

[0127] By being substantially composed of…, it will be understood herein that the matrix powder contains at least 97%, preferably at least 99%, of copper, nickel, aluminum, and zinc. Typically, the other component comprises at most 3% by mass, preferably at most 1% by mass, relative to the total mass of the alloy. Preferably, the other components, by mass, may include:

[0128] • Up to 1% chromium;

[0129] • Up to 1% manganese; and / or

[0130] • At most 1% iron.

[0131] As a non-limiting example, the cupronickel matrix powder may include (relative to the total mass of the matrix powder):

[0132] • 68.1% (±0.4%) copper by mass;

[0133] • 15.4% (±0.1%) of nickel by mass;

[0134] • 9.02% (±0.06%) aluminum by mass;

[0135] • 7.5% (±0.1%) of zinc by mass; and

[0136] • 640 ppm (m) of oxygen;

[0137] It should be understood that the sum of the components equals 100%.

[0138] The bulk density of cupronickel powder is typically 1 to 6 g / cm³. 3 Especially 4.5 to 5.5 g / cm 3 The actual density of cupronickel powder is typically 4 to 9 g / cm³. 3 Especially 7.5 to 9.0 g / cm 3 .

[0139] The particle size of cupronickel powder is advantageously between 15 and 45 μm. The D50 value of cupronickel matrix powder is typically between 20 and 30 μm.

[0140] advantage

[0141] Therefore, due to the above invention, the wear resistance and thermal conductivity of the glass manufacturing mold 1 can be improved. Thus, the frequency of glass manufacturing mold replacement can be reduced by completely coating the molding surface of the glass manufacturing mold with a coating having good wear resistance (e.g., a NiCr coating), or by using a cheaper mold to mold large quantities of glass or soda-lime glass, whose molding surface is simply covered with a coating having good thermal conductivity (e.g., a cupronickel alloy coating).

[0142] Therefore, the cost of purchasing and replacing molds can be reduced.

[0143] Example of surface treatment of metal component 1

[0144] An example of the treatment of the metal surface of a metal component will now be described.

[0145] Example 1

[0146] Preparation of metal powder 4

[0147] Metal powder 4 is obtained by mixing NiCr matrix powder with TiO2 lubricating powder in the following proportion:

[0148] - 95% by mass NiCr powder, which contains 50% by mass nickel and 50% by mass chromium (i.e., 47.5% by mass nickel and 47.5% by mass chromium in the total powder); and - 5% by mass titanium dioxide powder.

[0149] Mix these powders for 17.5 hours to obtain a uniform metal powder 4, and place it in a sealed chamber until use.

[0150] The NiCr powder used consists of an alloy containing approximately 50% by mass of nickel and approximately 50% by mass of chromium. It is sold by SANDVIK OSPREY.

[0151] The melting point of NiCr compounds is 1345℃.

[0152] The NiCr powder contains at least 75% by mass, advantageously at least 80% by mass, spherical particles relative to the total weight of the NiCr powder.

[0153] The average bulk density after three measurements was 4.7 g / cm³. 3 .

[0154] The powder sample used for the true density measurement was 30.8561 g. The average true density after five measurements was 7.71 g / cm³. 3 The standard deviation is 0.001.

[0155] Three measurements were performed to determine the parameters D10, D50, and D90 (laser particle size analysis). The average values ​​of these parameters are as follows: - D10 = 14.7 μm; - D50 = 26.1 μm; and - D90 = 44.0 μm.

[0156] The TiO2 powder used was sold by Saint Gobain under the name "TiO2 anatase nanostructure powder".

[0157] The TiO2 powder comprises at least 95% by weight, and advantageously at least 98% by weight, spherical particles relative to the total weight of the TiO2 powder. The surface appearance of the particles is very smooth. At least 80% by weight of the particles have internal pores relative to the total weight of the TiO2 powder.

[0158] The average bulk density after three measurements was 1.2 g / cm³. 3 .

[0159] The true density was measured under the same conditions as for NiCr, with a powder test sample of 7.3359 g. The average true density after five measurements was 4.16 g / cm³. 3 The standard deviation is 0.002.

[0160] Laser particle size analysis was performed under the same conditions as for the NiCr compound: the average values ​​of these parameters are as follows: - D10 = 8.80 μm; - D50 = 17.8 μm; and - D90 = 33.9 μm.

[0161] Prepare a plate representing the metal surface of a metal component.

[0162] Prepare 5 flat plates. Each plate has a free surface representing a metal part, such as the molded surface 2 of a glass manufacturing mold 1 designed to receive glass droplets.

[0163] The five plates 22 are made of graphite cast iron with the same layered microstructure.

[0164] Each plate 22 has its free surface covered with a coating obtained according to method 100 of this disclosure. Each plate 22 has its free surface 21 covered with a lubricating coating 6 obtained according to method 100 of this disclosure, having the following parameters:

[0165]

[0166] For each of these boards, use the following parameters:

[0167] - Laval type ceramic nozzle 7 (convergent-divergent), with an outlet diameter of 6mm;

[0168] - Powder flow rate: 2.89 cm 3 / min;

[0169] - Spraying gas 3: Nitrogen;

[0170] - Spraying gas flow rate: 4m 3 / h;

[0171] - Coolant: Distilled water;

[0172] - Metal powder 4: composed of nickel-chromium and titanium dioxide, as described in Example 1, at room temperature (20°C); and

[0173] - Number of passes: 10

[0174] The efficiency of cold spraying parameters can be evaluated by measuring the thickness of the resulting deposit:

[0175]

[0176] Plate 5 has the optimal thickness. The deposition efficiency of plate 1 is also satisfactory.

[0177] The porosity of the coating is evaluated by making slices of the coating.

[0178] By increasing pressure and temperature parameters (40 bar - 900°C to 50 bar - 1000°C), a comparison of plates 3 and 4 showed equivalent efficiency and similar porosity. Plate 3 was produced with a 2 mm sweep spacing and a speed of 200 mm / s, while the coating of plate 1 was produced with a 1 mm spacing and a speed of 400 mm / s. As a result, the reduction in spacing and the increase in spraying speed allowed for an increase in deposition thickness and a decrease in porosity (assessed by image analysis, 1.0% ± 0.5 for plate 1 and 2.3% ± 0.3 for plate 3).

[0179] The comparison between plates 1 and 5 shows the gain in efficiency (the ratio between the mass of the coating obtained and the mass of powder sprayed onto the plate) by increasing the temperature of the spraying gas from 1000°C (plate 1) to 1100°C (plate 2). The deposition efficiencies (abbreviated as %DE) for plates 1 and 5 are 52% and 68%, respectively.

[0180] The spraying distance was optimized to 20mm because the thickness deposited on plates 3 and 2 was slightly reduced (20mm and 35mm).

[0181] Plate 5 results in the thickest coating and, most importantly, in very good compactness, exhibiting very low porosity. The porosity of the coating on plate 5, quantitatively assessed by image analysis, is 0.3% ± 0.05, while that on plate 3 is 2.3 ± 0.3.

[0182] The table below shows the pore size index (area equivalent diameter) of the coatings on plates 3 and 5 calculated through image analysis. The minimum pore size considered is 0.99 μm².

[0183]

[0184] The median pore size (area equivalent) is three times smaller in the coating of plate 5 than in the coating of plate 3. It should be noted that these pore size values ​​are satisfactory for applications in glass manufacturing molds.

[0185] Image analysis showed that the coating adhesion of plate 3 was 83.7% and that of plate 5 was 98.4%, demonstrating the superior performance of the parameterization of plate 5.

[0186] No cracks were found on any of the plates and cross sections analyzed.

[0187] From the perspectives of thickness, porosity, efficiency, and bonding strength, the coating on plate 5 is optimal. The roughness of coating 5 is 7.0 μm (measured using a Mitutoty SJ210 roughness meter).

[0188] For NiCr powder, the optimized spraying parameters are as follows:

[0189]

[0190]

[0191]

[0192] Example 2

[0193] Preparation of metal powder 4

[0194] Metal powder 4 is obtained by mixing NiCr matrix powder with TiO2 lubricating powder in the following proportion:

[0195] - 95% by mass NiCr powder, which contains 78.7% by mass nickel (±0.6%) and 20.10% by mass chromium (±0.05%) (i.e., in the total powder, 39.35% by mass nickel and 10.1% by mass chromium);

[0196] - 5% by mass of titanium dioxide powder.

[0197] The NiCr powder used was Metco 43VF-NS powder sold by SANDVIK OSPREY.

[0198] The exact composition of the powder is as follows:

[0199]

[0200] *Oxygen content is quantified using instrumental gas analysis.

[0201] Mix these powders for 17.5 hours to obtain a uniform metal powder 4, and place it in a sealed chamber until use.

[0202] The melting point of NiCr compounds is 1345℃.

[0203] NiCr powder contains irregularly shaped particles.

[0204] The average bulk density after three measurements was 4.6 g / cm³. 3 .

[0205] The average value of the true density after 5 measurements was 8.30 g / cm³. 3 .

[0206] Three measurements were performed to determine parameters D10, D50, and D90 (laser particle size analysis). The average values ​​of these parameters are as follows:

[0207] - D10 = 11.7 μm;

[0208] - D50 = 21.6 μm; and

[0209] - D90=36.6 μm.

[0210] The TiO2 powder used is the same as that used in Example 1.

[0211] Prepare a plate representing the molding surface of a glass manufacturing mold.

[0212] Seven plates 22 were prepared using 80 / 20NiCr powder in the same manner as in Example 1.

[0213] The seven plates 22 are made of graphite cast iron with a layered microstructure having the same composition.

[0214] Each plate 22 has its free surface 21 covered with a lubricating coating 6 obtained according to method 100 of this disclosure, having the following parameters:

[0215]

[0216] For each of these boards, use the following parameters:

[0217] - Laval type ceramic nozzle 7 (convergent-divergent), with an outlet diameter of 6mm;

[0218] - Powder flow rate: 2.45 cm 3 / min;

[0219] - Spraying gas 3: Nitrogen;

[0220] - Spraying gas flow rate: 4m 3 / h;

[0221] - Coolant: Distilled water;

[0222] - Metal powder 4: composed of nickel-chromium and titanium dioxide, as described in Example 2, at room temperature (20°C); and

[0223] - Number of passes: 10

[0224] The efficiency of cold spraying parameters is evaluated by measuring the thickness of the obtained deposit:

[0225]

[0226] The coatings on plates 1, 5, and 7 exhibited optimal thickness. The coatings were obtained with a 1mm pitch and a sweep speed of 400mm / s. Therefore, this is relevant to the spray pitch and sweep speed parameters.

[0227] Analysis of the coatings on plates 1, 2, 3, 4 and 7 indicates that it is advantageous to use lower pressure / temperature parameters for spraying 80 / 20NiCr.

[0228] The efficiency obtained is satisfactory for all boards (e.g., 88% for board 5 and 65% for board 2). The efficiency of board 1 is calculated to be 80%.

[0229] The porosity of the coating was evaluated by preparing cross-sections of the coating. The coating exhibited very good metallurgical quality, with porosity between 1.5% and 4%.

[0230] The porosity of the coating was evaluated by preparing cross-sections of the coating. The coatings on plates 1 to 6 exhibited very good metallurgical quality, with porosities between 1.5% and 3%.

[0231] For each plate, the coating adhesion is greater than 95%. The coating on plate 7 has lower adhesion and higher porosity, which results in poorer metallurgical quality: this is due to the low temperature and pressure of the sprayed gas (800°C and 40 bar).

[0232] The table below shows the pore size index (area equivalent diameter) of the coatings on plates 1 and 7 calculated through image analysis. The minimum pore size considered is 0.99 μm².

[0233]

[0234] No cracks were found on any of the plates and cross sections analyzed.

[0235] From the perspectives of thickness, porosity, efficiency, and bonding strength, the coating on plate 1 is optimal. The roughness of coating 1 is 6.5 μm (measured using a Mitutoty SJ210 roughness meter).

[0236] Example 3

[0237] Preparation of metal powder 4

[0238] Metal powder 4 is obtained by mixing a base powder of cupronickel with a lubricating powder of TiO2 in the following proportion:

[0239] - 95% by mass of cupronickel powder; and - 5% by mass of titanium dioxide powder.

[0240] The cupronickel powder used was sold by NANOVAL. The exact composition of the powder is as follows:

[0241]

[0242] Mix these powders for 17.5 hours to obtain a uniform metal powder 4, and place it in a sealed chamber until use.

[0243] The powder has a melting point of 1235℃.

[0244] Apart from a few very irregular clusters, cupronickel powder consists of spherical particles. The particles do not have many satellites.

[0245] The average bulk density after three measurements was 4.6 g / cm³. 3 .

[0246] The average value of the true density after 5 measurements was 7.44 g / cm³. 3 .

[0247] Three measurements were performed to determine parameters D10, D50, and D90 (laser particle size analysis). The average values ​​of these parameters are as follows:

[0248] - D10 = 14.8 μm;

[0249] - D50 = 24.4 μm; and

[0250] - D90=40.0 μm.

[0251] The TiO2 powder used is the same as that used in Example 1.

[0252] Prepare a plate representing the molding surface of a glass manufacturing mold.

[0253] Eight plates 22 were prepared using 80 / 20NiCr powder in the same manner as in Example 1.

[0254] The eight plates 22 are made of graphite cast iron with the same layered microstructure.

[0255] Each plate 22 has its free surface 21 covered with a lubricating coating 6 obtained according to method 100 of this disclosure, having the following parameters:

[0256]

[0257] For each of these boards, use the following parameters:

[0258] - Laval type ceramic nozzle 7 (convergent-divergent), with an outlet diameter of 6mm;

[0259] - Powder flow rate: 2.5 cm 3 / min;

[0260] - Spraying gas 3: Nitrogen;

[0261] - Spraying gas flow rate: 4m 3 / h;

[0262] - Coolant: Distilled water;

[0263] - Metal powder 4: composed of cupronickel and titanium dioxide, as described in Example 3, at room temperature (20°C); and

[0264] - Number of passes: 10

[0265] The efficiency of cold spraying parameters is evaluated by measuring the thickness of the obtained deposit:

[0266]

[0267] The coatings on plates 1 to 3 are too thin, indicating that the temperature of the spraying gas must be at least 800°C. The efficiency gain is also quite significant when the spraying temperature increases from 800°C to 900°C. Then, for spraying temperatures greater than or equal to 900°C, the efficiency remains stable.

[0268] The porosity of the coating was evaluated by preparing cross-sections of the coating. The coating exhibited very good metallurgical quality, with porosities between 0.3% and 2%. The porosity of the coating on plate 7 was, for example, 0.3%, while the porosities of plates 5 and 8 were 1.4% and 1.0%, respectively.

[0269] The porosity of the coating was evaluated by preparing cross-sections of the coating. The coatings on plates 1 to 6 exhibited very good metallurgical quality, with porosities between 1.5% and 3%.

[0270] The table below shows the pore size index (area equivalent diameter) of the coatings on plates 1 and 7 calculated through image analysis. The minimum pore size considered is 0.99 μm².

[0271]

[0272] The bonding rates of plates 5 and 7 are 72% and 88% respectively, which are very good.

[0273] No cracks were found on any of the plates and cross sections analyzed.

[0274] From the perspectives of thickness, porosity, efficiency, and bonding strength, the coating on plate 7 is optimal. The roughness of coating 7 is 7.6 μm (measured using a Mitutoty SJ210 roughness meter).

[0275] For cupronickel powder, the optimized spraying parameters are as follows:

[0276]

[0277]

[0278]

Claims

1. A surface treatment method (100) for treating a metal surface of a metal part configured to contact a preform, such as the molding surface (2) of a glassware mold (1), said surface treatment method (100) comprising the following steps: - Solid metal powder (4) is cold-sprayed (110) onto a metal surface to obtain a solid deposit (5); and - Machining (120) the solid deposit (5) to obtain a coating (6).

2. The surface treatment method (100) according to claim 1, wherein, The metal powder (4) is sprayed using a spraying gas (3) subjected to a pressure greater than 30 bar, for example 40 bar to 70 bar, for example about 50 bar.

3. The surface treatment method (100) according to claim 1 or 2, wherein, The metal powder (4) is sprayed using a spraying gas (3) heated to a temperature of 750°C or higher, particularly 800°C or higher, for example, 900°C to 1150°C.

4. The surface treatment method (100) according to any one of claims 1 to 3, wherein, During the spraying step (110), the spraying distance corresponding to the distance between the nozzle (7) used for spraying the metal powder (4) and the metal surface (2) includes between 15 mm and 60 mm, preferably between 15 mm and 35 mm, for example equal to about 20 mm or about 30 mm.

5. The surface treatment method (100) according to any one of claims 1 to 4, wherein, During the spraying step (110), the travel speed of the nozzle (7) for spraying the metal powder (4) during spraying is between 200 mm / s and 1000 mm / s, for example, between 200 mm / s and 450 mm / s.

6. The surface treatment method (100) according to any one of claims 1 to 5, wherein, The spraying step (110) is carried out for a sufficient time to obtain a solid deposit (5) with a thickness of 0.3 mm to 3 mm, preferably 0.5 mm to 2.5 mm.

7. The surface treatment method (100) according to any one of claims 1 to 6, wherein the injection flow rate of the metal powder (4) in the spraying gas (3) comprises 1 to 10 cm⁻¹ 3 Between / min, preferably between 2 and 3cm 3 Between / min, for example, about 2.5 cm 3 / min.

8. The surface treatment method (100) according to any one of claims 1 to 7, wherein, The coating (6) has better wear resistance than the metal surface (2).

9. The surface treatment method (100) according to any one of claims 1 to 7, wherein, The coating (6) has a higher thermal conductivity than the metal surface (2).

10. The surface treatment method (100) according to any one of claims 1 to 9, wherein, The metal powder (4) is basically composed of NiCr powder.

11. The surface treatment method (100) according to any one of claims 1 to 9, wherein, The metal powder (4) consists substantially of the following by mass relative to the total mass of the powder: • 60-70%, preferably 62-68% copper; •7-17%, preferably 10-15% nickel; • 5-15%, preferably 8-12% aluminum; and •5-15%, preferably 8-12% zinc; It should be understood that the sum of the components equals 100%.

12. A metal component (1), such as a glass manufacturing mold, comprising: - Metal surface (2), said metal surface (2) is configured as a contact blank; and - A coating (6) that covers all or part of the metal surface (2) and comprises a metal alloy, the metal alloy being obtained by cold spraying metal powder (4) onto the metal surface (2) by a surface treatment method (100) according to any one of claims 1 to 9.

13. The metal component (1) according to claim 12, wherein, The metal surface (2) includes at least one of the following materials: graphite cast iron having a layered, worm-like or spherical microstructure, copper and tin based alloys such as bronze, carbon steel, fire-resistant steel or stainless steel, or brass.

14. The metal component (1) according to any one of claims 12 to 13, wherein, The metal powder (4) is basically composed of nickel and chromium.

15. The metal component (1) according to any one of claims 12 and 13, wherein, The coating (6) is obtained by cold spraying a metal powder consisting essentially of NiCr powder or a metal powder consisting essentially of the following by mass relative to the total mass of the powder: • 60-70%, preferably 62-68% copper; •7-17%, preferably 10-15% nickel; • 5-15%, preferably 8-12% aluminum; and •5-15%, preferably 8-12% zinc, It should be understood that the sum of the components equals 100%.

16. The metal component of claim 15, the metal component comprising a glass manufacturing mold, the metal surface corresponding to the molding surface of the glass manufacturing mold and comprising at least one of the following materials: graphite cast iron, carbon steel, fire-resistant steel or stainless steel having a layered, worm-like or spherical microstructure.

17. An apparatus comprising: - A machine (10) for surface treatment of metal parts, such as glass manufacturing molds (1), comprising: - A support member (17) configured to receive a metal component (1), said metal component (1) having a metal surface (2) configured to contact a blank; and - Nozzle (7), which is configured to cold spray solid metal powder (4) onto the metal surface (2) to obtain a solid deposit (5), and - A processing station (11) configured to process the solid deposit (5) and obtain a coating (6).

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