JP2006193765A - Method for producing member made of aluminum alloy - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for producing a member made of an aluminum alloy where the eutectic fusion of Al-Cu compounds in solution treatment is prevented. <P>SOLUTION: The stock 12 to be worked formed of an aluminum alloy is subjected to forging at a high working degree in such a manner that the eutectic fusion of Al-Cu compounds in the stock 12 to be worked by the subsequent solution treatment is prevented, and a scroll 13 after the forging is subjected to solution treatment and aging treatment. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a method for producing an aluminum alloy member.

  The scroll is used for a compressor or the like constituting an air conditioner such as an air conditioner, and its shape is shown in FIG. The scroll 101 includes an end plate 102, a wrap 103 extending spirally from one end surface of the end plate 102, and a cylindrical attachment portion 104 formed on the other end surface of the end plate 102. The scroll compressor combines the scrolls 101 so that the wraps 103 face each other, and revolves one of the scrolls 101 with respect to the other scroll 101 to compress the fluid between the wraps 103 of both scrolls 101. Is.

  In recent years, scrolls are often made of an aluminum alloy (Al—Si—Cu—Mg alloy) for weight reduction and the like, and the manufacturing method has been mainly casting.

  A conventional scroll manufacturing method by general casting is shown in FIGS. FIG. 12A shows a manufacturing method by cutting a continuous cast bar. In this method, a casting rod 105 extruded by continuous casting is cut and peeled to form a material 106 having a predetermined size. Then, a solution treatment and an aging heat treatment are performed on the material 106 in order to improve the strength, and then a scroll 107 is manufactured by machining and finishing by machining or the like. FIG. 2B shows a manufacturing method by casting. In this method, first, a scroll 108 made of an aluminum alloy is cast-molded by a mold or the like, and then solution treatment and aging heat treatment are performed in order to improve the strength. Thereafter, machining and finishing are performed.

  Such a conventional method for producing an aluminum alloy casting scroll is disclosed in, for example, Patent Document 1.

JP 2000-192180 A

  However, scrolls made of an aluminum alloy are not only lighter, but also require higher strength. This can be dealt with by increasing the amount of Cu that composes the aluminum alloy. For example, a conventional aluminum alloy scroll is made of Al-9Si-2Cu-0.4Mg, but can be made by forming it with an aluminum alloy of Al-9Si-4Cu-0.35Mg. However, if the solution is changed and the solution treatment is performed under the same conditions as in the prior art, defects may occur in the material.

  The defect of the material which arises during this solution treatment is demonstrated using Fig.13 (a), (b). The figure (a) is an organization chart of the scroll after casting, and the figure (b) is an organization chart of the scroll after the solution treatment (510 ° C. × 5H) and the aging treatment (T6 treatment: 170 ° C. × 6H). is there.

  As shown in FIG. 13A, when the added amount of Cu increases, the Al—Cu compound particles become coarse and intervene in the structure. Si has a function of dissolving the Al—Cu compound, and Mg has a function of lowering the melting point of the Al—Cu compound to make the Al—Cu compound a low melting point compound. As a result, it takes time until the Al—Cu compound is dissolved in the Al mother layer by diffusion in the temperature rising process of the solution treatment, and Si and Mg are dissolved before the Al—Cu compound dissolves and disappears. As a result, the Al—Cu compound is dissolved while the diffusion is insufficient. As shown in FIG. 5B, the portion where the Al—Cu compound is dissolved becomes a cavity in the structure, resulting in a material defect. Such a phenomenon is called eutectic melting. If eutectic melting occurs during the heat treatment of the material, there is a possibility of adversely affecting the quality and the like of the subsequent cast product.

  Furthermore, in recent years, it has been understood that it is more advantageous to manufacture by forging than casting due to problems such as strength and productivity of the scroll, and scrolls are used in forged products. The scroll manufacturing method by forging is performed using a forging die, and the upsetting process is performed to form the upsetting material into a work material of a predetermined shape before the forging process so that it can be inserted into the forging die. Is to do. However, even in the conventional aluminum alloy forging scroll, no measures have been taken for the eutectic melting described above.

  Therefore, this invention solves the said subject, and it aims at providing the manufacturing method of the member made from an aluminum alloy which prevents the eutectic fusion of the Al-Cu compound at the time of solution treatment.

The method for producing an aluminum alloy member according to the first invention for solving the above-mentioned problems is as follows.
A work material formed of an aluminum alloy is forged at a high degree of work so that the Al-Cu compound in the work material does not become a cavity by a subsequent solution treatment,
The forging material is subjected to solution treatment and aging treatment after forging.

The method for producing an aluminum alloy member according to the second invention for solving the above-mentioned problems is as follows.
An aluminum alloy is formed into a casting material by continuous casting,
Forming the casting material into a workpiece by ring cutting and peeling,
The work material is forged at a high workability so that the Al-Cu compound in the work material does not become a cavity by a subsequent solution treatment,
The forging material is subjected to solution treatment and aging treatment after forging.

The method for producing an aluminum alloy member according to the third invention for solving the above-mentioned problems is as follows.
The upsetting material formed of an aluminum alloy is upset processed at a high degree of processing so that the Al-Cu compound in the upsetting material does not become a cavity by a subsequent solution treatment,
A solution treatment and an aging treatment are performed on the upsetting material after forging.

The method for producing an aluminum alloy member according to the fourth invention for solving the above-mentioned problems is as follows.
An aluminum alloy is formed into a casting material by continuous casting,
The casting material is formed into an upsetting material by ring cutting and peeling,
The upsetting material is upset processed at a high degree of processing so that the Al-Cu compound in the upsetting material does not become a cavity by a subsequent solution treatment,
A solution treatment and an aging treatment are performed on the upsetting material after forging.

The method for producing an aluminum alloy member according to the fifth invention for solving the above-described problems is as follows.
In order to prevent the Al-Cu compound in the aluminum alloy from becoming cavities by the subsequent solution treatment, a cast material is formed by continuously extruding at a high workability.
Forming the casting material into a workpiece by ring cutting and peeling,
The forging material is subjected to solution treatment and aging treatment after forging.

A method for producing an aluminum alloy member according to a sixth invention for solving the above-described problems is as follows.
In the method for manufacturing an aluminum alloy member according to any one of the first to fifth inventions,
The aluminum alloy is formed so that the Cu addition amount is 4.2 wt% or less,
A high workability is imparted so as to introduce a strain of ε ≧ 1.5.

A manufacturing method of an aluminum alloy member according to a seventh invention for solving the above-described problems is as follows.
In the method for producing an aluminum alloy member according to any one of the first to sixth inventions,
The manufactured member is a scroll.

  According to the method for manufacturing an aluminum alloy member according to the first aspect of the present invention, the work material formed of the aluminum alloy is formed such that the Al—Cu compound in the work material does not become a cavity by the subsequent solution treatment. By performing forging at a high degree of processing and subjecting the material to be processed to solution treatment and aging treatment after forging, eutectic melting of the Al—Cu compound during solution treatment can be prevented.

  According to the method for manufacturing an aluminum alloy member according to the second invention, an aluminum alloy is formed into a cast material by continuous casting, the cast material is formed into a work material by ring cutting and peeling, and the work is processed. The material is forged at a high degree of processing so that the Al-Cu compound in the material to be processed does not become a cavity by the subsequent solution treatment, and the solution material and the aging treatment are performed on the material to be processed after forging. By doing so, eutectic melting of the Al—Cu compound during the solution treatment can be prevented.

  According to the method for producing an aluminum alloy member according to the third aspect of the invention, the upsetting material formed of the aluminum alloy is not hollowed by the subsequent solution treatment of the Al-Cu compound in the upsetting material. Thus, the eutectic melting of the Al-Cu compound during the solution treatment is prevented by performing upsetting at a high degree of processing and performing solution treatment and aging treatment on the upsetting material after forging. be able to.

  According to the method for manufacturing an aluminum alloy member according to the fourth aspect of the present invention, an aluminum alloy is formed into a casting material by continuous casting, the casting material is formed into an upsetting material by ring cutting and peeling processing, and the mounting The upsetting material is upset with a high workability so that the Al-Cu compound in the upsetting material does not become a cavity by the subsequent solution treatment, and after the forging, the upsetting material is subjected to a solution treatment and By performing the aging treatment, eutectic melting of the Al—Cu compound during the solution treatment can be prevented.

  According to the method for manufacturing an aluminum alloy member according to the fifth invention, a cast material is formed by continuously extruding at a high degree of processing so that the Al—Cu compound in the aluminum alloy does not become a cavity by a subsequent solution treatment. In addition, the cast material is formed into a work material by ring cutting and peeling, and after the forging, the work material is subjected to solution treatment and aging treatment, so that Al-Cu at the time of solution treatment is obtained. Eutectic melting of the compound can be prevented.

  According to the method for producing an aluminum alloy member according to the sixth invention, in the method for producing an aluminum alloy member according to the first to fifth inventions, the amount of Cu added to the aluminum alloy is 4.2 wt% or less. By forming a high degree of work so as to introduce a strain of ε ≧ 1.5, eutectic melting of the Al—Cu compound during the solution treatment can be prevented.

  According to a seventh aspect of the present invention, there is provided a method for producing an aluminum alloy member, wherein the member to be produced is a scroll in the method for producing an aluminum alloy member according to any one of the first to sixth aspects. Since eutectic melting of the Cu compound can be prevented, the high-strength scroll can be manufactured.

  Embodiments of a vehicle body structure according to the present invention will be described below in detail with reference to the drawings.

  First, Embodiment 1 will be described with reference to FIGS. FIG. 1 is a view showing a manufacturing process flowchart of a scroll according to Embodiment 1 of the present invention, FIG. 2 is a view showing chemical components of an aluminum alloy, FIG. 3 is a view showing forging conditions, and FIG. Cross-sectional view of the scroll after solution treatment and T6 treatment, FIG. 5B is an enlarged view of position I in FIG. 8A, FIG. 8C is an enlarged view of position II in FIG. FIG. 5 and FIG. 5 are schematic views of an Al—Cu compound imparted with a high workability.

  As shown in FIG. 1, the aluminum alloy melted by adjusting the alloy components is continuously cast and then cut to form a cast bar 11. This aluminum alloy is composed of Al-9Si-4Cu-0.35Mg, and its chemical composition is shown in FIG. Next, the cast rod 11 is formed into a workpiece 12 by being subjected to a ring cutting process so as to have a predetermined length (height) and then being peeled. The diameter of the casting rod 11 is generally matched to the outer shape of the forged product, and the workpiece 12 is a forging material.

  Next, although not shown, the work material 12 is forged using a forging die, and the scroll 13 is formed. A high degree of processing is imparted to the workpiece 12 by this forging. The forging conditions at this time are shown in FIG. The scroll 13 is subjected to solution treatment and aging treatment in order to obtain strength after forging. The conditions for the solution treatment in this example were 510 ° C. × 5H, and the conditions for the aging treatment (T6 treatment: hereinafter referred to as T6 treatment) were 170 ° C. × 6H. Thereafter, the surface of the scroll 13 is finished by cutting or the like in order to obtain dimensional accuracy.

  And as shown to Fig.4 (a), cross-sectional observation of the structure | tissue of the scroll 13 after solution treatment and T6 process was performed in the position of I and II. FIG. 5B shows a cross-sectional observation of the base of the wrap (position I), and FIG. 5C shows a cross-section observation of the end plate (position II). As a result, it is understood that eutectic melting does not occur at the position I which is the high workability region, and eutectic melting occurs at the position II which is the low workability region.

  In this embodiment, a high workability is imparted by holding the workpiece 12 at a high temperature and compressively deforming it during forging. In addition, by keeping the workpiece 12 at a high temperature, the workpiece 12 is easily deformed and is less likely to crack. Thereby, as shown in FIG. 5, the Al-Cu compound formed in a substantially spherical shape is crushed into a plate shape, and the specific surface area is increased as compared with that before forging. That is, the Al—Cu compound has a larger area in contact with the Al mother layer. Therefore, the diffusion of the Al—Cu compound is promoted in the temperature raising process of the solution treatment, the time required for the diffusion is shortened, and the Al—Cu compound is easily dissolved in the Al mother layer.

  Thus, even if the amount of Cu added is increased in order to increase the strength of the scroll formed of the aluminum alloy, a high workability is imparted to the Al-Cu compound, which is a low melting point eutectic compound, and the specific surface area is increased. By doing so, the Al—Cu compound disappears during the temperature raising process of the solution treatment, and thus eutectic melting can be prevented.

  For example, even if eutectic melting occurs in the vicinity of a low degree of work, it is unlikely that it will be the starting point of fatigue strength if it is in the vicinity of the surface layer of the scroll, and it can be considered that it can be used sufficiently if the use conditions are selected. That is, forging is understood as an effective process for preventing eutectic melting.

  Therefore, according to the method for producing an aluminum alloy member according to the present invention, an aluminum alloy is formed on the cast material 11 by continuous casting, and the cast material 11 is formed on the work material 12 by ring cutting and peeling, The work material 12 is forged and formed at a high degree of work so that the Al—Cu compound in the work material 12 is not eutectic melted by the subsequent solution treatment, so that the scroll 13 is formed. Further, by performing the T6 treatment, eutectic melting of the Al—Cu compound during the solution treatment can be prevented. Further, since such a defect (cavity) is eliminated, the high-strength scroll 13 can be manufactured.

  Next, Example 2 will be described with reference to FIGS. 6 is a view showing a manufacturing process flowchart of the scroll according to the second embodiment of the present invention, FIG. 7 is a view showing upsetting conditions, FIG. 8A is a cross-sectional structure of the scroll after solution treatment and T6 treatment. Fig. 9 (b) is an enlarged view of position III in Fig. 9 (a), Fig. 9 is a diagram showing the shape of the upsetting material and the amount of compression strain introduced, and Fig. 10 is the presence or absence of eutectic melting. It is the figure which showed the relationship between the compressive strain which affects and Cu addition amount.

  As shown in FIG. 6, the aluminum alloy melted by adjusting the alloy components is continuously cast and then cut to form a cast bar 14. This aluminum alloy is composed of Al-9Si-4Cu-0.35Mg as in Example 1, and its chemical composition is the same as that shown in FIG. Next, the cast bar 14 is ring-cut so as to have a predetermined length (height), and then peeled to form the upsetting material 15, which is upset. Thus, the workpiece 16 is formed. This upsetting process gives a high degree of processing. The upsetting conditions at this time are shown in FIG. In general, the diameter of the workpiece 16 is generally matched to the outer shape of the forged product.

  Next, although not shown, the work material 16 is forged using a forging die, and the scroll 17 is formed. The forging conditions at this time are the same as those shown in FIG. The scroll 13 is subjected to solution treatment and aging treatment in order to obtain strength after forging. The conditions for the solution treatment in this example were 515 ° C. × 5H, and the conditions for the aging treatment (T6 treatment: hereinafter referred to as T6 treatment) were 170 ° C. × 6H. Thereafter, the surface of the scroll 17 is finished by cutting or the like in order to obtain dimensional accuracy.

  And as shown to Fig.8 (a), cross-sectional observation of the structure | tissue of the scroll 17 after solution treatment and T6 process was performed in the position of III. FIG. 5B is a cross-sectional observation of the base of the wrap (position III). As a result, the scroll 17 provided with high workability by upsetting has a uniform high workability region as a whole, and no eutectic melting has occurred.

  The upsetting process performed in the present embodiment is different from the conventional upsetting process in which the upsetting material is formed into a workpiece material having a predetermined shape, and not only the upsetting material 15 is formed into a predetermined shape, High-temperature compression deformation that imparts a high degree of processing is also performed. In addition, by keeping the workpiece 12 at a high temperature, the workpiece 12 is easily deformed and is less likely to crack.

  By performing upsetting as described above, as shown in FIG. 5, the Al-Cu compound formed in a substantially spherical shape is crushed into a plate shape, and the specific surface area is increased as compared with that before the upsetting. That is, the Al—Cu compound has a larger area in contact with the Al mother layer. Therefore, the diffusion of the Al—Cu compound is promoted in the temperature raising process of the solution treatment, the time required for the diffusion is shortened, and the Al—Cu compound is easily dissolved in the Al mother layer. In other words, the upsetting process intentionally performs a structure control in which the structure in the material is deformed.

  Thus, even if the amount of Cu added is increased in order to increase the strength of the scroll formed of the aluminum alloy, a high workability is imparted to the Al-Cu compound, which is a low melting point eutectic compound, and the specific surface area is increased. By doing so, the Al—Cu compound disappears during the temperature raising process of the solution treatment, and thus eutectic melting can be prevented.

  Here, preparation materials made of an aluminum alloy with Cu addition amounts of 2.0, 3.5, and 4.2 wt% are prepared, and the compression strain ε of each installation material to the work material is 0. Upsetting was carried out to 0.0, 0.5, 1.0, 1.2, and 1.5. Thus, the relationship between the Cu addition amount and the compressive strain ε will be analyzed.

  FIG. 9 shows the shape common to each upsetting material A to E with 2.0, 3.5, and 4.2 wt% of Cu addition and the magnitude of the compressive strain ε introduced during the upsetting process. It is. ho indicates the height of the upsetting material, and Do indicates the diameter. Since the upsetting material A is 2.0 wt% before increasing the amount of Cu added, there is no need for upsetting, so the compression strain ε is 0.0.

  FIG. 10 shows the presence or absence of eutectic melting by analyzing the scroll structure after solution treatment and T6 treatment after forging the workpiece material upset under the conditions of FIG. Those in which eutectic melting occurred were marked with x, and those in which eutectic melting did not occur were marked with ○.

  As shown in FIG. 10, when the Cu addition amount is 2.0 wt%, eutectic melting does not occur at each compression strain. In the case of 3.5, 4.2 wt%, eutectic melting did not occur only when the compressive strain was ε = 1.5. As a result, if the Cu addition amount is 4.2 wt% or less, eutectic melting can be prevented by imparting a high degree of processing such that the compressive strain is ε ≧ 1.5.

  In addition, by performing upsetting before forging, it is possible to increase the degree of work in the low workability region where the degree of work cannot be raised in forging, reducing the overall Al-Cu compound of the forged product, Eutectic melting is prevented.

  Note that, as in the first and second embodiments, the aluminum alloy may be compressed so as to impart a high degree of workability during continuous extrusion without being applied during forging or upsetting.

  Therefore, according to the method for manufacturing an aluminum alloy member according to the present invention, an aluminum alloy is formed on the casting material 14 by continuous casting, the casting material 14 is formed on the upsetting material 15 by ring cutting and peeling, The upsetting material 15 is upset processed at a high degree of processing so that the Al-Cu compound in the upsetting material 15 is not eutectic melted by the subsequent solution treatment, and formed into the workpiece 16, By forming the workpiece 16 by forging and forming it into the scroll 17 and subjecting the scroll 17 to solution treatment and T6 treatment, it is possible to prevent eutectic melting of the Al—Cu compound during the solution treatment. it can.

  Also, eutectic melting is reliably prevented by forming an aluminum alloy so that the amount of Cu added is 4.2 wt% or less and imparting a high workability so as to introduce a compressive strain of ε ≧ 1.5. can do.

  The present invention is applicable to parts formed of an aluminum alloy for the purpose of preventing eutectic melting after solution treatment.

It is the figure which showed the manufacturing process flowchart of the scroll which concerns on Example 1 of this invention. It is the figure which showed the chemical component of the aluminum alloy. It is the figure which showed the forging conditions. (A) is a cross-sectional view of the structure of the scroll after solution treatment and T6 treatment, (b) is an enlarged view of position I in FIG. (A), and (c) is an enlarged view of position II in FIG. FIG. It is a schematic diagram of the Al-Cu compound to which the high workability was provided. It is the figure which showed the manufacturing process flowchart of the scroll which concerns on Example 2 of this invention. It is the figure which showed the upsetting conditions. (A) is the structure | tissue sectional drawing of the scroll after solution treatment and T6 process, (b) is an enlarged view of the position of III of the figure (a). It is the figure which showed the shape of the upsetting material, and the amount of introduction of compression strain. It is the figure which showed the relationship between the compressive strain which affects the presence or absence of eutectic melting, and Cu addition amount. It is the schematic of the scroll which concerns on one Example of the past. (A) is the figure which showed the manufacturing process flowchart of the scroll by the cutting of the continuous casting rod concerning one conventional example, (b) showed the manufacturing process flowchart of the scroll by casting which concerns on one conventional example. FIG. (A) is the organization chart of the scroll after casting, (b) is the organization chart of the scroll after a solution treatment and an aging treatment.

Explanation of symbols

11, 14 Casting rods 12, 16 Work material 13, 17 Scroll 15 Upsetting material

Claims (7)

A work material formed of an aluminum alloy is forged at a high degree of work so that the Al-Cu compound in the work material does not become a cavity by a subsequent solution treatment,
A method for producing an aluminum alloy member, wherein a solution treatment and an aging treatment are performed on the workpiece after forging. An aluminum alloy is formed into a casting material by continuous casting,
Forming the casting material into a workpiece by ring cutting and peeling,
The work material is forged at a high workability so that the Al-Cu compound in the work material does not become a cavity by a subsequent solution treatment,
A method for producing an aluminum alloy member, wherein a solution treatment and an aging treatment are performed on the workpiece after forging. The upsetting material formed of an aluminum alloy is upset processed at a high degree of processing so that the Al-Cu compound in the upsetting material does not become a cavity by a subsequent solution treatment,
A method for producing an aluminum alloy member, wherein the upsetting material is subjected to a solution treatment and an aging treatment after forging. An aluminum alloy is formed into a casting material by continuous casting,
The casting material is formed into an upsetting material by ring cutting and peeling,
The upsetting material is upset processed at a high degree of processing so that the Al-Cu compound in the upsetting material does not become a cavity by a subsequent solution treatment,
A method for producing an aluminum alloy member, wherein the upsetting material is subjected to a solution treatment and an aging treatment after forging. In order to prevent the Al-Cu compound in the aluminum alloy from becoming cavities by the subsequent solution treatment, a cast material is formed by continuously extruding at a high workability.
Forming the casting material into a workpiece by ring cutting and peeling,
A method for producing an aluminum alloy member, wherein a solution treatment and an aging treatment are performed on the workpiece after forging. In the manufacturing method of the aluminum alloy member according to any one of claims 1 to 5,
The aluminum alloy is formed so that the Cu addition amount is 4.2 wt% or less,
A high workability is imparted so as to introduce a strain of ε ≧ 1.5. A method for producing an aluminum alloy member. In the manufacturing method of the aluminum alloy member according to any one of claims 1 to 6,
The member manufactured is a scroll. The manufacturing method of the member made from aluminum alloy characterized by the above-mentioned.