JPS61238947A - Manufacture of al-si alloy blank - Google Patents

Abstract

PURPOSE:To obtain an Al-Si alloy blank having superior wear resistance and workability by mixing powder of an Al-Si alloy having a specified composition as the 1st alloy with powder of an Al-Si alloy having a specified composition as the 2nd alloy in a specified ratio, and by compacting the mixture so as to regulate the average and maximum diameters. CONSTITUTION:Powder of an Al-Si alloy consisting of 15-34% Si and the balance Al as the 1st alloy is mixed with powder of an Al-Si alloy consisting of 35-50% Si and the balance Al as the 2nd alloy in 1:(0.05-2) ratio. The mixture is compacted so as to regulate the average diameter of the Si grains to 5-15mum and the maximum diameter to 10-30mum.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention is applicable to, for example, cylinder blocks, cylinder liners, cylinder sleeves, pistons and valve train parts (valve lifters, valve spring retainers, valve seat rings, rockers) of internal combustion engines. The present invention relates to a method of manufacturing Al-Si alloy materials used for automobile synchronizer rings, rotary compressor vanes, VTR cylinders, etc.

[Prior Art] As this type of alloy, hypereutectic Arr-s alloys have been known that have excellent properties such as wear resistance, low thermal expansion, and heat resistance.

In this alloy, as the amount of Si added increases, properties such as wear resistance and low thermal expansion can be improved. Processability such as hardness, rollability, forgeability, machinability, polishability, etc. became inferior, and the amount of Si added was reduced to 35%.
It cannot be increased by more than %.

As a means to solve this problem, P is added to the alloy and Si
Although a method of making particles finer is known, even with this method it is still not possible to reduce the size of primary Si particles to 30 to 40 μm or less.

On the other hand, as a means of making Si particles finer, Si15-3
It is known that alloy powder is produced using a rapid solidification method using a 5% alloy at a cooling rate of 100° C./sec or more, and this powder is molded to make the average diameter of Si particles 1 to 5 μl. . However, according to this method, the primary crystal Si becomes too fine, so that the wear resistance is rather deteriorated.

Problem to be Solved by the Invention 1 From the above, in order to have wear resistance and improve workability, it is necessary to set the average diameter of Si particles to 5 to 15 μm and the maximum diameter to 10 to 30 μm. There is.

However, by simply manufacturing an alloy powder from an A1 alloy containing 35 to 50% Si and molding it, the above-mentioned Si
Although it is possible to achieve a certain particle size, the material produced by this method has significantly poor ductility and processability, making it impractical.

The present invention was achieved by exploring the problems of the above-mentioned conventional technology.
It is an object of the present invention to provide a manufacturing method capable of obtaining an i-based alloy material.

[Means for solving the problems] The present invention, which has been made to achieve the above object, is based on Si15
~ 34%, the remainder Amonohena-Si alloy manufactured from the first
of alloy powder, Si 35-50%, balance AM A1-
and a second alloy powder manufactured from a Si alloy at a ratio of 1:0.0.
They are mixed at a ratio of 5 to 2 and molded, and the average diameter of the Si particles is set to 5.
It is characterized by having a thickness of ~15 μm and a maximum diameter of 10 to 30 μm.

Here, in addition to the above-mentioned elements, the first and second alloy powders contain Cu0.5-10 to add age hardening properties.
%, M (10, 3 to 6%, may also contain 20,
In addition, to add heat resistance, Fe%Mn 1N
It may contain 9% or less of i, Co, and Zr.

In addition, for the production of alloy powder, for example, an atomization method using rapid solidification, a so-called roll method (single roll method, twin roll method) in which atomized metal is sprayed onto a roll, or a centrifugal atomization method can be used. It is manufactured so that the average particle size is 5 to 300 μm.

Forming methods after mixing the powders include sintering, hot pressing, and HI P (Hot Isostatic Pr).
Methods such as essing), extrusion, forging or rolling can be used.

[Function] By mixing and molding two A1-Si alloy powders with different Si component concentrations, A1 with Si of 35 to 50%
In the case of the A4 alloy powder, wear resistance is ensured because the primary crystal Si particle size is large, while in the case of the A1 alloy powder containing 15 to 34% Si, the Si particle size itself is small, so that workability is improved. Therefore, by utilizing the characteristics of the 100% alloy powder, it is possible to produce an excellent Ajl-Si alloy material that has both wear resistance and workability.

[Example] Examples of the present invention will be described below.

As shown in Figure 1, A1 containing 15-34% Si
Powders of alloys and Heme alloys containing 35 to 50% Si and having various compositions shown in Table 1 were manufactured using an atomization method. That is, a molten metal having the above alloy composition is dropped into a gas fluid, and in a gas atomized state,
Cooled at a cooling rate of 10 to 10'C/sec to form first and second alloy powders A1 to A5 with an average particle size of 70 μm;
B1 to B4 were manufactured.

Next, as shown in Table 2, 2p of the above alloy powder
Class J was mixed and filled into a cylindrical mold with a diameter of 60.2ml and a height of 2001mm, and compression molding was performed by uniaxial compression at a pressure of 30 kg/mmz.

Furthermore, after performing vacuum degassing treatment, hot extrusion processing was performed to produce the material. As conditions for extrusion processing, a temperature of 430° C., an extrusion speed of 1 m/min, and an extrusion ratio of 15 were adopted.

Next, among the combinations in Table 1, samples other than sample No. 10, which did not contain Cu or Mg, were subjected to age hardening treatment, and sample No. 10 was not subjected to this treatment. In the above age hardening treatment, first, solution treatment is performed at 500°C for 1 hour, then water-cooled, and then further heated to 175°C.
Tempering was performed for 6 hours.

In addition, as a comparative example, the same treatment was performed on an alloy powder made of an AM-Si alloy with a single composition, and Table 1 shows
Also listed in Table 2.

Next, for each of the above-mentioned materials, the particle diameter was measured, the wear resistance was determined based on the size of the particle diameter, and the workability in terms of hot extrudability, hot forgeability, tensile strength, and elongation was examined.

In the above test, the wear resistance was judged based on the size of the Si particles, since the wear resistance improved depending on the size of the Si particles.

On the other hand, hot extrudability was visually inspected for the presence or absence of cracks in the material obtained by hot extrusion processing. In addition, for the hot forgeability test, the diameter of the material after extrusion was 141 mm.
A sample with a length of 11L and 151 mm was formed, heated to 450° C., and forged at an upsetting rate (height reduction rate) of 50%, and hot forgeability was evaluated based on the presence or absence of cracks.

As shown in Table 2, according to this example, 8115-3
A first alloy powder consisting of 4%-A1 alloy and Si35~
50% - a second alloy powder consisting of A1 alloy at a mixing ratio of 1
:0.2 to 2 and molded. As a result, the maximum diameter of the Si particles is 19 to 29 μm, and 813 μm in the comparative example.
Since the maximum diameter corresponding to 5% or more (No. 915 to 18) is secured, wear resistance is improved, and moreover, the comparative example No.
15 to 18 have poor workability and mechanical properties such as tensile strength, elongation, hot extrudability, and hot forgeability, whereas this example has excellent workability and mechanical properties. .

[Effects of the Invention] As explained above, according to the present invention, an A1-5+ alloy material having excellent wear resistance and workability can be manufactured.

[Brief explanation of the drawing]

FIG. 1 is a process diagram showing a manufacturing method according to an embodiment of the present invention.

Claims (1)

[Claims] A first alloy powder manufactured from an Al-Si alloy containing 15 to 34% Si and the balance Al and a second alloy powder manufactured from an Al-Si alloy containing 35 to 50% Si and the balance Al at 1:0.
．． A method for producing an Al-Si alloy material, characterized in that the Si particles are mixed at a ratio of 0.05 to 2 and molded, and the average diameter of Si particles is 5 to 15 μm, and the maximum diameter is 10 to 30 μm.