Method for making metal ring using beryllium copper alloy and metal ring

Abstract

The invention discloses a method for making a metal ring with a beryllium copper alloy and a metal ring, wherein the metal ring has a fine and uniform grain structure, and relates to the field of metal product manufacturing. Generally, a beryllium copper billet containing 1.6wt% to 2.0wt% beryllium is preheated, hot worked by forging, soaked, ring rolled to reduce the ring wall thickness by at least 50%, solution annealed, and heat treated.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application is a divisional application of the Chinese patent application with application number 201880074421.5. The Chinese patent application with application number 201880074421.5 is a Chinese national phase application of international application PCT / US2018 / 061524, which claims priority to the U.S. provisional patent application serial number 62 / 587,533 filed on November 17, 2017, and its entire contents are incorporated herein by reference. Technical Field

[0003] The present disclosure relates to a metal rim or metal ring for casting amorphous metal. In particular, the ring of the present disclosure is made of beryllium copper alloy. A method of making the ring is disclosed and will be described with particular reference to the ring. Background Art

[0004] Beryllium-copper ("BeCu") alloys are known for their excellent combination of thermal conductivity, strength, toughness, impact energy, and corrosion resistance. Other advantages of BeCu alloys include relatively high electrical conductivity, ultrasonic inspectability, and good thermal management. This combination of properties makes BeCu alloys ideal for a wide range of applications. However, there is a need to find more economical methods for processing BeCu alloys.

[0005] Conventional metal rings have problems with surface quality life, ductility, formability, ultrasonic inspectability, conductivity, and lack of grain size refinement. The metal rings disclosed herein solve these problems while simplifying product manufacturing and reducing costs. Summary of the invention

[0006] The present disclosure relates to beryllium copper metal rings having a fine and uniform grain structure and methods of forming the same. A rough beryllium copper casting is pre-forged and turned to form a beryllium copper billet. Typically, a cycle of heat treatment and cooling is performed to achieve the material property of maintaining surface quality of the ring for a long time while enabling the customer to obtain higher productivity from each ring casting. Broadly speaking, the beryllium copper billet is preheated, hot worked by forging, reheated, hot worked again by ring rolling, then air cooled, solution annealed, then quenched, and air cooled after the last heating.

[0007] In various embodiments herein, a method for making a metal ring is disclosed, the method comprising providing a blank made of a beryllium copper alloy. The blank is preheated at a temperature of about 800° C. to about 850° C. (including about 820° C.) for a period of at least 8 hours. The blank is then hot worked by forging the blank into an annular preform at a temperature of about 750° C. to about 850° C. Forging may include press forging and piercing to produce an annular blank.

[0008] Next, the preform is soaked at a temperature of about 815°C to about 835°C (including about 820°C). The soaking can be performed for a period of at least 2 hours or at least 8 hours. In some specific embodiments, if the preform has been cooled to a temperature of about 600°C or less, the preform is soaked for a period of at least 8 hours. The preform is then hot-worked again by ring-rolling the preform at a temperature of about 750°C to about 850°C to form a ring having a wall thickness that is desirably substantially uniform around the circumference of the ring.

[0009] After ring rolling, the ring is air-cooled. The ring is then solution annealed at a temperature of about 780°C to about 800°C for at least 1.5 hours. Immediately after solution annealing, the ring is quenched in a quenching medium (e.g., water). Typically, the maximum temperature of the quenching medium before quenching is about 40°C, and the maximum temperature after quenching is about 50°C. The ring is then age-hardened by heat treating at a temperature of about 385°C to about 400°C for about 3 hours. In a particular embodiment, the approximately 3-hour period begins at a temperature of about 393°C and is heated to about 400°C. The temperature of 400°C is then maintained for the remainder of the time. After heat treatment, the ring is air-cooled.

[0010] In some embodiments, the ring may be machined to obtain the final desired shape.

[0011] The beryllium content of the beryllium copper alloy used to make the metal ring is about 1.6wt% to about 2.0wt%, including about 1.8wt% to about 2.0wt% and about 1.6wt% to about 1.85wt%. In some specific embodiments, the beryllium content of the beryllium copper alloy is about 1.8wt% to about 1.9wt%. The balance of the beryllium copper alloy is usually copper. In some embodiments, the beryllium copper alloy also contains about 0.2wt% to about 0.3wt% cobalt; or also contains about 0.2wt% to about 0.6wt% lead; or also contains a certain amount of nickel, cobalt and optional iron, so that the sum of (nickel + cobalt) is about 0.2wt% or higher than 0.2wt%, and the sum of (nickel + cobalt + iron) is about 0.6wt% or lower than 0.6wt%.

[0012] In some embodiments, the hot working achieved by ring rolling reduces the wall thickness by at least 50%. In other embodiments, the wall thickness is reduced by at least 70% or more in total throughout the process (ie, all process steps).

[0013] For approximately every 25 millimeters (mm) of ring wall thickness, solution annealing may be performed for approximately 30 minutes.

[0014] In another embodiment of the present invention, a metal ring made by the above method is disclosed. The metal ring is made of a beryllium copper alloy having a beryllium content of about 1.6 wt% to about 2.0 wt%, including about 1.8 wt% to about 2.0 wt% and about 1.8 wt% to about 1.9 wt%, and the balance is essentially copper. The beryllium copper metal ring also has a 0.2% offset yield strength of at least 760 MPa; a Rockwell C hardness of at least 27 HRC; a percent elongation of at least 6%; an electrical conductivity of at least 25% IACS; and / or an average grain size of less than 0.1 mm.

[0015] These and other non-limiting features of the present disclosure are more particularly disclosed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The following is a brief description of the drawings, which are presented to illustrate exemplary embodiments disclosed herein and not to limit the same.

[0017] Figure 1 is a flow chart of a first exemplary method of making a metal ring from a beryllium copper ("BeCu") alloy, the method including various heat treatment and cooling steps.

[0018] Figure 2 is a flow chart of a second exemplary method of making a metal ring from a beryllium copper alloy, the method including various heat treatment and cooling steps.

[0019] Figure 3 is a diagrammatic illustration of a rolling operation utilizing an exemplary ring rolling mill for forming the beryllium copper metal rings disclosed herein.

[0020] Figure 4 is a cross-sectional view of an exemplary beryllium copper metal ring preform formed by the methods disclosed herein. DETAILED DESCRIPTION

[0021] A more complete understanding of the components and methods disclosed herein may be obtained by referring to the accompanying drawings. These figures are merely schematic representations for convenience and ease of illustrating the present disclosure, and are therefore not intended to indicate the relative size and dimensions of the device or its components, and / or are not intended to define or limit the scope of the exemplary embodiments.

[0022] Although specific terms are used in the following description for the sake of clarity, these terms are intended to refer only to the specific structures of the embodiments selected for the illustration in the drawings, and are not intended to define or limit the scope of the present disclosure. In the drawings and the following description, it should be understood that similar numerical numerals represent components with the same functions.

[0023] Unless the context clearly dictates otherwise, unmodified nouns and nouns modified by "the" include singular and plural referents.

[0024] As used in the specification and claims, the term "comprising / including" may include the embodiments of "consisting of" and "consisting essentially of." The terms "comprising," "including," "having," "may," "containing," and variations thereof as used herein refer to open transitional phrases, terms, or words that require the presence of specified components / steps and allow for the presence of other components / steps. However, such descriptions should be interpreted as also describing a composition or method as "consisting of" and "consisting essentially of" the listed components / steps, which allows for the presence of only the specified components / steps and any impurities that may result therefrom, and excludes other components / steps.

[0025] Numerical values ​​in the specification and claims of this application should be understood to include the same numerical values ​​when reduced to the same number of significant figures and numerical values ​​that differ from the stated value by less than the experimental error of ordinary measurement techniques of the type described in this application for determining the stated value.

[0026] All ranges disclosed herein are inclusive of the indicated endpoints and are independently combinable (eg, the range of "2 grams to 10 grams" includes the endpoints 2 grams and 10 grams, and all intermediate values).

[0027] The term "about" can be used to include any numerical value that can vary without changing the basic function of the value. When used with a range, "about" also discloses the range defined by the absolute values ​​of the two endpoints, for example, "about 2 to about 4" also discloses a range of "2 to 4". The term "about" can mean ±10% of the indicated number.

[0028] The present disclosure relates to steps for processing metal alloys / articles occurring at specified temperatures. It should be noted that the temperatures referred to herein are the temperatures of the atmosphere to which the metal alloy is exposed, i.e., the temperatures at which the heating device (e.g., furnace) is set. The metal alloy itself does not necessarily reach these temperatures.

[0029] The present disclosure refers to "uniform" wall thickness. This term allows for variations in wall thickness and should be understood to include values ​​that are identical when reduced to the same number of significant figures and values ​​that differ from the stated value by less than the experimental error of ordinary measurement techniques.

[0030] Metal edges or metal rings are used in methods and equipment related to industrial machinery, wind power plants, high power gears, offshore technology, rings and support rings for slewing bearings, turbines, generators, transformers, hydraulic motors, valves, pipelines, textile machinery, tanks / pressure vessels, gear rings, aerospace, bulk feed presses, steel mills, including but not limited to bearings, clutches, couplings, drives, flanges, etc. However, conventional rings wear quickly, which increases the number of rings that need to be purchased each year.

[0031] The beryllium copper rings disclosed herein are produced by a novel heat treatment process that imparts material properties that provide the surface of the ring with greater stability for a longer period of time and allow more metal to be cast on the ring until the surface has to be reworked or a replacement ring purchased. In particular, the metal rings currently disclosed are made from a beryllium copper ("BeCu") alloy that provides a combination of properties suitable for enhancement by heat treatment and quenching / cooling cycles described in further detail below. These enhanced properties include, but are not limited to, yield strength, hardness, ductility, electrical conductivity, fine and uniform grain structure, and ultrasonic inspectability. The fine and uniform grain structure and maximum electrical conductivity are produced by the process steps of cascading overaging followed by overaging and excessive solution annealing.

[0032] refer to Figure 1 , an exemplary method (S100) for making a metal ring according to a first embodiment starts at S101, and the method includes a cycle of multiple heat treatments and quenching / cooling. In S102, a beryllium copper metal alloy blank is provided or received. In S104, the blank is preheated at a temperature of about 800° C. to about 850° C. (including about 820° C.) for a period of at least 8 hours. The preheating step is intended to obtain a temperature as uniform as possible throughout the thickness of the blank so that the subsequent steps uniformly affect all metal alloys in the blank.

[0033] In S106, the blank is hot worked into an annular preform. In particular, the blank is forged into an annular preform. Hot working is a metal forming method in which the cross section of an alloy is reduced to form a desired shape and size, usually at a temperature above the recrystallization temperature of the alloy. This generally reduces directionality in mechanical properties and produces a new equiaxed microstructure.

[0034] Forging is a process of compressing the thickness of a workpiece by applying heat and pressure to expand the cross section of the workpiece or otherwise change the shape of the workpiece. This plastically deforms the alloy and is usually done above the recrystallization temperature. This improves the mechanical properties, increases ductility, further homogenizes the alloy, and refines the coarse grains.

[0035] During forging, hot working must generally be maintained within a controlled temperature range to avoid forging defects. For example, too high a temperature may result in initial melting, while too low a temperature may result in surface cracking. In any case, the forging temperature should be high enough to allow recrystallization without promoting excessive microstructural grain growth. Therefore, the hot working of S106 is performed at a temperature of about 750°C to about 850°C. Preferably, a temperature of about 770°C to about 834°C is maintained during hot working.

[0036] The first hot working step can be performed by multiple forging steps, including but not limited to press forging and punching. Press forging refers to the slow and continuous application of pressure on the beryllium copper billet. In particular, press forging generally includes upsetting of the beryllium copper billet, wherein pressure is applied to the longitudinal axis of the billet to form the billet into a pancake shape. Upsetting also causes directional grain flow within the billet. During the punching process, a hole is cut in the middle of the beryllium copper billet that has been flattened during press forging. As a result of punching, the beryllium copper billet is transformed into an annular preform, wherein the annular shape is generally toroidal or "doughnut-like". Alternatively, punching can be performed instead of punching or in combination with punching, in which case the punch removes the bulk of the middle portion of the beryllium copper billet.

[0037] In S108, the preform is soaked at a temperature of about 815°C to about 835°C (including about 820°C). Again, this is intended to obtain a temperature as uniform as possible throughout the thickness of the blank for subsequent processing. The soaking generally lasts for at least 2 hours, and in some embodiments may last for at least 8 hours. In a specific embodiment, the soaking lasts for a period of about 2 hours to about 8 hours.

[0038] In S110, the preform is ring-rolled at a temperature of about 750° C. to about 850° C. to form a ring with a uniform wall thickness, and then air-cooled. The temperature should be maintained during the entire ring-rolling step. The ring rolling is preferably performed at a temperature of about 770° C. to about 834° C. The ring rolling reduces the wall thickness by at least 50%. In other words, the hot working forging performed on the ring-shaped preform generally reduces the area of ​​the casting by at least 50%.

[0039] After ring rolling, the rings are air-cooled. For this purpose, the beryllium copper rings are removed from the furnace and exposed to ambient temperature. If necessary, air cooling can be done actively, i.e. ambient air is blown towards the rings.

[0040] In S112, the ring is solution annealed at a temperature of about 780°C to about 800°C for a time of at least 1.5 hours. Typically, for approximately every 25 mm of ring wall thickness, the solution annealing in S112 should be performed for a time of about 30 minutes.

[0041] After the solution annealing, the ring is immediately quenched in a quenching medium in S114. The quenching medium should have a maximum temperature of about 40°C before quenching and a maximum temperature of about 50°C after quenching. This quenching method will quickly change the temperature of the beryllium copper ring and generally obtain a single phase.

[0042] In S116, the ring is age-hardened by heat treatment at a temperature of about 385°C to about 400°C for about 3 hours, and then air-cooled. Optionally, the ring can be machined in S118. Through these steps, a beryllium copper metal ring with a fine uniform grain size is formed.

[0043] refer to Figure 2 , another exemplary method (S200) for making a metal ring according to the second embodiment starts at S201. A beryllium copper metal alloy billet is provided in S202. In S204, the billet is preheated at a temperature of about 800°C to about 850°C (including about 820°C) for at least 8 hours. In S206, the billet is hot worked into an annular preform. Again, as described above, hot working must be generally maintained within a controlled temperature range to avoid forging defects. Therefore, the billet is forged into an annular preform at a temperature of about 750°C to about 850°C. Preferably, a temperature of about 770°C to about 834°C is maintained during the hot working process.

[0044] In S208, if the preform has been cooled to a temperature of about 600°C or less, the preform is soaked at a temperature of about 815°C to about 835°C (including about 820°C) for about 8 hours (including at least 8 hours). In S210, the preform is ring-rolled at a temperature of about 750°C to about 850°C to form a ring with uniform wall thickness, and then air-cooled. Likewise, the ring rolling is preferably performed at a temperature of about 770°C to about 834°C. In S212, the ring is solution annealed at a temperature of about 780°C to about 800°C for at least 1.5 hours. Typically, for approximately every 25 mm of the wall thickness of the ring, the solution annealing in S212 is performed for about 30 minutes.

[0045] After the solution annealing, in S214, the ring is immediately quenched in a quenching medium. The quenching medium is typically water. The quenching medium should have a maximum temperature of about 40°C before quenching and a maximum temperature of about 50°C after quenching.

[0046] In S216, the ring is age-hardened by heat treatment at a temperature of about 385°C to about 400°C for about 3 hours, and then air-cooled. Optionally, the ring can be machined in S218 to form a beryllium copper amorphous metal ring with fine uniform grain size.

[0047] exist Figure 1 and Figure 2 In the particular embodiment shown, during the heat treatment step (S116, S216), the approximately 3 hour period begins at a temperature of approximately 393° C. The temperature is raised to approximately 400° C. and maintained at that temperature for the remainder of the period.

[0048] More generally, Figure 1 and Figure 2 The method shown relates to making a beryllium copper ring with fine uniform grain size. A rough beryllium copper casting is pre-forged and turned into a blank for making a ring. A beryllium copper metal alloy blank is provided (S102, S202). The blank is preheated to a first temperature of about 800°C to about 850°C (including about 820°C), and preheated for a first time of at least 8 hours (S104, S204). The blank is subjected to a first hot working forging to form a ring preform (S106, S206). The ring preform is then soaked for a second time of at least 2 hours at a second temperature of about 815°C to about 835°C (S108, S208). A second hot working forging is performed by ring rolling, followed by air cooling to form a ring with uniform wall thickness (S110, S210). Then, the ring is exposed to a third temperature of about 780°C to about 800°C for a third time (S112, S212). Immediately after the third temperature and the third time, the ring is cooled by quenching (S114, S214). The ring is then heated to a fourth temperature lower than the first, second and third temperatures and for a fourth time, and then air-cooled to the final ambient temperature to produce a ring with a fine uniform particle size (S116, S216). If necessary, the ring can be machined in S118, S218. Machining may include, but is not limited to, sawing, drilling, tapping, boring, milling, turning, grinding, polishing, reaming, electrical discharge machining (EDM), etc., in order to obtain the desired final shape of the beryllium copper metal ring. The final shape of the beryllium copper metal ring can be based on the application in which the ring is used.

[0049] Figure 1 and Figure 2The method shown generally causes a total reduction in wall thickness of at least 70%. In general, the reduction rate of the beryllium copper ring preform should be large enough to allow the deformation to penetrate the entire processing area. Partial penetration (especially in the final stage of ring rolling) will not produce the desired uniform dynamic recrystallization in the beryllium copper ring. Insufficient deformation can lead to inhomogeneity of microstructure and mechanical properties after age hardening in method steps (S116, S216).

[0050] The degree of reduction can be determined by measuring the change in the cross-sectional area of ​​the ring wall before and after hot ring rolling, or before preheating and after heat treatment or optional finishing, according to the following formula:

[0051] %HW=100*[A 0 -A f ] / A 0

[0052] Among them A 0 is the initial or raw cross-sectional area before hot working, and A f is the final cross-sectional area after hot working. It should be noted that changes in cross-sectional area are usually only due to changes in alloy thickness, so %HW can also be calculated using initial and final thicknesses.

[0053] The furnace used in the heat treatment method described herein preferably meets the requirements of AMS2750 or equivalent NORSOK requirements for high temperature determination. The solution annealing in the method steps (S112, S212) is preferably carried out in a Class 5 furnace, more preferably in a Class 2 furnace. The age hardening or heat treatment steps of (S116, S216) are preferably carried out in a Class 2 furnace. The definition of furnace grades is described in AMS2750 or equivalent NORSOK.

[0054] exist Figure 1 and Figure 2 In the two embodiments shown, the second hot working forging ( S110 , S210 ) is usually performed by ring rolling on a rolling mill. Figure 3 An exemplary ring rolling operation 300 is shown that includes a ring rolling mill 302. During the ring rolling process, a beryllium copper annular preform 304 is placed on an idler roll 306. The idler roll 306 is generally disposed within a hollow portion 308 of the annular preform 304 and acts on an inner surface 310 or a diameter thereof. A drive roll 312 is generally disposed against an outer surface 314 or a diameter of the annular preform. An upper axial roll 316 is disposed against a top surface 320 of the preform. A lower axial roll 318 is disposed against a bottom surface 322 of the preform.

[0055] Pressure is continuously applied to the preform 304 by the idler roller 306, the drive roller 312, the upper axial roller 316 and the lower axial roller 318. Pressure is continuously applied until the desired inner diameter, outer diameter, height and / or wall thickness of the ring is achieved. In general, the purpose of ring rolling is to fully process the cross section of the ring to be as uniform as possible to minimize the difference in grain size after recrystallization. An average grain size of less than about 0.1 mm is desirable.

[0056] Figure 4 is a cross-sectional view of a preform 304, which may also represent the finished ring. The preform has an inner diameter D i and outer diameter D o The wall thickness T of the ring is the difference between these two diameters. The ring also has a height H. The diameter is measured from the central axis 305.

[0057] In some embodiments, the beryllium copper ring may have an outer diameter D of about 250 mm to about 8,000 mm, including about 350 mm to about 2,000 mm. o The inner diameter of the beryllium copper ring is D i It can be at least about 150 mm to about 350 mm. The beryllium copper ring generally has a wall thickness T of less than about 700 mm to about 800 mm. The height H of the beryllium copper ring is generally about 20 mm to about 900 mm, including about 200 mm to about 300 mm.

[0058] Inner surface 310 is generally smooth. Outer surface 314, upper surface 320, and lower surface 322 are shown as being flat, however they may be shaped as desired for the application / device in which the ring is to be used.

[0059] As a result of the exemplary method steps described above, a metal ring made of beryllium copper having a variety of advantageous properties is formed. These advantageous properties include, but are not limited to, strength, hardness, ductility, electrical conductivity, and refined grain size. In particular, the advantageous properties include any combination of the following: a 0.2% residual deformation yield strength of at least 760 MPa; a Rockwell C hardness of about 27 HRC to about 33 HRC; a percent elongation of at least 6%; an electrical conductivity of at least 25% of the International Annealed Copper Standard (International Annealed Copper Standard, "IACS", where 100% IACS equals 5.8×107 Siemens / meter or 1.72 microohm centimeters); and an average grain size of less than 0.1 mm. The average grain size is measured in the axial direction of a slice taken from the rolled ring and on the inner surface of the slice closest to the finished part. The 0.2% residual deformation yield strength is measured according to ASM E8. The Rockwell C hardness is measured according to ASTM E18. The % elongation is measured according to ASTM E3. The electrical conductivity is measured according to ASTM E1004.

[0060] The beryllium copper alloy used to form the metal ring includes about 1.6 wt % to about 2.0 wt % beryllium, including about 1.8 wt % to about 2.0 wt % and about 1.8 wt % to about 1.9 wt % beryllium.

[0061] The beryllium copper alloy may also contain small amounts of cobalt (Co), nickel (Ni), iron (Fe) and / or lead (Pb). In some embodiments, the beryllium copper alloy may also contain about 0.2 wt % to about 0.3 wt % cobalt. In other embodiments, the beryllium copper alloy may contain about 0.2 wt % to about 0.6 wt % lead.

[0062] In other embodiments, the sum of cobalt and nickel in the beryllium copper alloy is at least 0.2 wt%. In other embodiments, the sum of cobalt, nickel and iron in the beryllium copper alloy is at most 0.6 wt%. It should be noted that all three elements do not need to be present. Such an alloy may contain at least one of nickel or cobalt, but may only contain nickel or cobalt. Iron is not required to be present, but in some specific embodiments, iron is present in an amount of about 0.1 wt% or more (up to the stated limit).

[0063] In some specific embodiments, the beryllium copper alloy comprises about 1.8 wt% to about 2.0 wt% beryllium; at least 0.2 wt% cobalt and nickel in total; up to 0.6 wt% cobalt, nickel and iron in total; and the balance copper. The alloy is commercially available from Materion Corporation as Alloy 25. Alloy 25 has an elastic modulus of about 131 GPa; a density of about 8.36 g / cc; a thermal conductivity of about 105 W / (m·K) at 25°C; a 0.2% residual deformation yield strength before heat treatment of about 130 MPa to about 280 MPa; a minimum ultimate tensile strength before heat treatment of about 410 MPa; and a minimum elongation before heat treatment of 35%.

[0064] In some specific embodiments, the beryllium copper alloy comprises about 1.6 wt% to about 1.85 wt% beryllium; at least 0.2 wt% cobalt and nickel in total; up to 0.6 wt% cobalt, nickel and iron in total; and the balance copper. The alloy is commercially available from Materion Corporation as Alloy 165. Alloy 165 has an elastic modulus of about 131 GPa; a density of about 8.41 g / cc; a thermal conductivity of about 105 W / (m·K) at 25°C; a 0.2% residual deformation yield strength before heat treatment of about 130 MPa to about 280 MPa; a minimum ultimate tensile strength before heat treatment of about 410 MPa; and a minimum elongation before heat treatment of 35%.

[0065] In other embodiments, the beryllium copper alloy comprises about 1.6 wt % to about 2.0 wt % beryllium; about 0.2 wt % to about 0.3 wt % cobalt; and the balance copper. or MoldMax Commercially available from Materion Corporation.

[0066] MoldMax The elastic modulus is about 131 GPa; the density is about 8.36 g / cc; and the thermal conductivity at 25°C is about 130 W / (m·K); the 0.2% residual deformation yield strength is about 1000 MPa; the typical ultimate tensile strength is about 1170 MPa; and the typical elongation is 5%.

[0067] MoldMax The elastic modulus is about 131 GPa; the density is about 8.36 g / cc; and the thermal conductivity at 25°C is about 155 W / (m·K); the 0.2% residual deformation yield strength is about 760 MPa; the typical ultimate tensile strength is about 965 MPa; and the typical elongation is 15%.

[0068] In other specific embodiments, the beryllium copper alloy contains about 1.8 wt% to about 2.0 wt% beryllium; at least 0.2 wt% cobalt and nickel in total; up to 0.6 wt% cobalt, nickel and iron in total; about 0.2 wt% to about 0.6 wt% lead; and the balance copper. The alloy is commercially available from Materion Corporation as Alloy M25. Alloy M25 has an elastic modulus of about 131 GPa; a density of about 8.36 g / cc; a thermal conductivity of about 105 W / (m·K) at 25°C; a 0.2% residual deformation yield strength before heat treatment of about 130 MPa to about 250 MPa; a minimum ultimate tensile strength before heat treatment of about 410 MPa; and a minimum elongation before heat treatment of 20%.

[0069] In some specific embodiments, the beryllium copper alloy comprises about 1.8 wt% to about 2.0 wt% beryllium; at least 0.2 wt% cobalt and nickel in total; up to 0.6 wt% cobalt, nickel and iron in total; and the balance copper. The alloy is commercially available from Materion Corporation as Alloy 190. Alloy 190 has an elastic modulus of about 131 GPa; a density of about 8.36 g / cc; and a thermal conductivity of about 105 W / (m·K) at 25°C.

[0070] In some specific embodiments, the beryllium copper alloy comprises about 1.8 wt% to about 2.0 wt% beryllium; at least 0.2 wt% cobalt and nickel in total; up to 0.6 wt% cobalt, nickel and iron in total; and the balance copper. The alloy is commercially available from Materion Corporation as alloy 290. Alloy 290 has an elastic modulus of about 131 GPa; a density of about 8.36 g / cc; and a thermal conductivity of about 105 W / (m·K) at 25°C.

[0071] As mentioned above, one benefit of using beryllium copper alloy for the rings of the present disclosure is the ability to perform ultrasonic inspection. Ultrasonic inspection is an effective and versatile nondestructive testing technique that can be used for defect detection / assessment, dimensional measurement, material characterization, etc. Ultrasonic testing is typically performed in accordance with AMS 2154 Type I and Class A or the equivalent EN 10228-4, Level 3. Depending on the size of the beryllium copper ring, it may be necessary to pre-machine the ring prior to ultrasonic inspection to provide a better surface finish for ultrasonic inspection and to allow for arbitrary movement of the ring prior to finishing.

[0072] The present disclosure has been described with reference to exemplary embodiments. Others may conceive of modifications and changes upon reading and understanding the foregoing detailed description. The present disclosure is intended to be interpreted as including all such modifications and changes, as long as such modifications and changes fall within the scope of the appended claims or their equivalents.

[0073] In some embodiments, the present application provides technical solutions in the following projects:

[0074] 1. A method for making a metal ring using a beryllium copper alloy, the method comprising:

[0075] preheating the beryllium copper alloy billet at a temperature of about 800° C. to about 850° C.;

[0076] forging the billet into an annular preform at a temperature of about 750° C. to about 850° C.;

[0077] soaking the preform at a temperature of about 815°C to about 835°C;

[0078] Ring rolling the preform at a temperature of about 750° C. to about 850° C. to form a ring having a wall thickness;

[0079] solution annealing the ring at a temperature of about 780°C to about 800°C and immediately quenching the ring; and

[0080] The ring is heat treated at a temperature of about 385°C to about 400°C.

[0081] 2. The method according to claim 1, wherein the preheating lasts for at least 8 hours.

[0082] 3. The method according to item 1, wherein the soaking lasts for at least 2 hours.

[0083] 4. The method according to item 3, wherein if the preform has been cooled to a temperature of about 600° C. or less, the soaking is performed for a period of at least 8 hours.

[0084] 5. The method according to item 1, wherein the solution annealing lasts for a period of at least 1.5 hours.

[0085] 6. The method according to item 1, wherein the heat treatment lasts for about 3 hours.

[0086] 7. The method according to item 6 further comprises: starting the time of about 3 hours at a temperature of about 393°C, increasing the temperature to about 400°C, and heat treating the ring at a temperature of about 400°C for the remaining time.

[0087] 8. The method according to item 1, wherein the preheating and soaking are both performed at a temperature of about 820°C.

[0088] 9. The method according to item 1, wherein the ring rolling reduces the wall thickness by at least 50%.

[0089] 10. The method according to item 1, wherein the solution annealing is performed for about 30 minutes for approximately every 25 mm of ring wall thickness.

[0090] 11. The method according to item 1, further comprising air cooling the ring after the ring rolling and the heat treatment.

[0091] 12. A metal ring comprising:

[0092] A beryllium copper alloy comprising about 1.6 wt % to about 2.0 wt % beryllium, wherein the beryllium copper alloy has:

[0093] 0.2% residual strain yield strength of at least 760MPa;

[0094] A Rockwell C hardness of at least 27 HRC; and

[0095] A percentage elongation of at least 6%.

[0096] 13. The ring of item 12, wherein the beryllium copper alloy contains about 1.8 wt% to about 2.0 wt% beryllium, or about 1.8 wt% to about 1.9 wt% beryllium.

[0097] 14. The ring of item 12, wherein the beryllium copper alloy further comprises about 0.2 wt % to about 0.3 wt % cobalt.

[0098] 15. The ring of item 12, wherein the beryllium copper alloy further comprises about 0.2 wt % to about 0.6 wt % lead.

[0099] 16. The ring according to item 12, wherein the beryllium copper alloy further comprises an amount of nickel, cobalt and optionally iron such that the sum of (nickel + cobalt) is about 0.2 wt % or more and the sum of (nickel + cobalt + iron) is about 0.6 wt % or less.

[0100] 17. The ring of item 12, wherein the beryllium copper alloy has an electrical conductivity of at least 25% IACS.

[0101] 18. The ring according to item 12, wherein the beryllium copper alloy has an average grain size of 0.1 mm or less, or wherein the beryllium copper alloy has a Rockwell C hardness of 27 HRC to about 33 HRC.

[0102] 19. A method for making a metal ring, comprising:

[0103] providing a billet made of a beryllium copper alloy comprising about 1.6 wt % to about 2.0 wt % beryllium;

[0104] preheating the billet at a temperature of about 800° C. to about 850° C. for a period of at least 8 hours;

[0105] forming the blank into an annular preform at a temperature of about 750° C. to about 850° C.;

[0106] soaking the preform at a temperature of about 815° C. to about 835° C. for a period of about 2 hours to about 8 hours;

[0107] Ring rolling the preform at a temperature of about 750° C. to about 850° C. until the preform has a substantially uniform wall thickness, followed by air cooling;

[0108] solution annealing the preform at a temperature of about 780°C to about 800°C for a period of at least 1.5 hours and immediately thereafter quenching in a quenching medium;

[0109] heat treating the preform at a temperature of about 385° C. to about 400° C. for a period of about 3 hours, followed by air cooling; and,

[0110] The preform is machined to form the metal ring into a desired shape.

[0111] 20. An amorphous metal casting apparatus comprising a metal ring, wherein the metal ring is made of a beryllium copper alloy containing about 1.6 wt % to about 2.0 wt % beryllium, wherein the beryllium copper alloy has:

[0112] 0.2% residual strain yield strength of at least 760MPa;

[0113] A Rockwell C hardness of at least 27 HRC; and

[0114] A percentage elongation of at least 6%.

Claims

1. A method for making a metal ring using a beryllium copper alloy, the method comprising: Preheating a beryllium copper alloy billet at a temperature of 800° C. to 850° C., wherein the beryllium copper alloy consists of 1.6 wt % to 2.0 wt % of beryllium, 0.2 wt % to 0.3 wt % of cobalt, and the balance of copper; Forging the blank into an annular preform at a temperature of 750° C. to 850° C.; soaking the preform at a temperature of 815°C to 835°C; Ring rolling the preform at a temperature of 750° C. to 850° C. to form a ring having a wall thickness, wherein the ring rolling reduces the wall thickness by at least 50%; The rings are solution annealed at a temperature of 780°C to 800°C and immediately quenched; and the rings are heat treated at a temperature of 385°C to 400°C.

2. The method according to claim 1, wherein: The heat treatment lasted for a period of 3 hours, and the 3 hour period was started at a temperature of 393°C, the temperature was increased to 400°C, and the ring was heat treated at a temperature of 400°C for the remaining time.

3. The method according to claim 1, wherein: The ring rolling reduces the wall thickness by at least 70%.

4. The method according to claim 1, wherein: The solution annealing was performed for 30 minutes for every 25 mm of ring wall thickness.

5. A method for making a metal ring, comprising: Providing a billet made of a beryllium copper alloy, wherein the beryllium copper alloy consists of 1.6 wt % to 2.0 wt % beryllium, 0.2 wt % to 0.3 wt % cobalt, and the balance copper; preheating the blank at a temperature of 800° C. to 850° C. for a period of at least 8 hours; forming the blank into an annular preform at a temperature of 750° C. to 850° C.; soaking the preform at a temperature of 815° C. to 835° C. for a period of 2 to 8 hours; Ring rolling the preform at a temperature of 750° C. to 850° C. until the preform has a substantially uniform wall thickness, followed by air cooling; Solution annealing the preform at a temperature of 780°C to 800°C for a period of at least 1.5 hours and immediately thereafter quenching in a quenching medium; heat treating the preform at a temperature of 385° C. to 400° C. for a period of 3 hours, followed by air cooling; And, the preform is machined to form the metal ring having a desired shape.

6. The method according to claim 5, wherein: The heat treatment lasted for a period of 3 hours, and the 3 hour period was started at a temperature of 393°C, the temperature was increased to 400°C, and the ring was heat treated at a temperature of 400°C for the remaining time.

7. The method according to claim 5, wherein: The ring rolling reduces the wall thickness by at least 70%.

8. The method according to claim 5, wherein: The solution annealing was performed for 30 minutes for every 25 mm of ring wall thickness.

9. A metal ring comprising: Beryllium copper alloy, which consists of 1.6wt% to 2.0wt% beryllium, 0.2wt% to 0.3wt% cobalt, and the balance copper, wherein: The beryllium copper alloy has: 0.2% residual strain yield strength of at least 760MPa; Ultimate tensile strength of at least 965Mpa; A Rockwell C hardness of at least 27 HRC; and, A percentage elongation of at least 6%.

10. The metal ring according to claim 9, wherein: The beryllium copper alloy has an average grain size of 0.1 mm or less.

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