JPS6063361A - Manufacture of wear resistant aluminum alloy material having oil retentivity - Google Patents

Abstract

PURPOSE:To obtain a wear resistant Al alloy material preventing the damage of the sliding surface due to short of oil by hot extruding a prescribed Al alloy contg. coarse proeutectic Si grains by >=50% of the total area of Si grains to destroy the proeutectic Si grains and to pierce a large number of pores. CONSTITUTION:An Al alloy contg. 12-30% Si, 0.3-5% Cu and 0.3-2% Mg is melted and cast to form an ingot contg. coarse proeutectic Si grains of 100- 200mum grain size by >=50% of the total area of Si grains. The ingot is hot extruded to destroy the proeutectic Si grains and to pierce a large number of pores. Thus, a wear resistant Al alloy material having oil retentivity and preventing the damage of the sliding surface due to lack of oil is obtd.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a manufacturing method of aluminum alloy 4A 1131 (7), which is used to improve the wear resistance of, for example, engine cylinder liners and compressor vanes. . .

In addition, in this specification, "%" (,1,
It shows the small amount %J.

Conventionally, aluminum alloys for the above uses have been made with C8i as the main additive element to increase wear resistance.
A wear-resistant Δp-s1 alloy containing J:< about 12 to 30% is generally known. In actual use of such an alloy member, it forms a sliding surface J:
In such a case, the sliding surface will be lubricated with oil, but if the equipment is restarted after stopping operation for a long time, the sliding surface will often run out of oil and be damaged. There is a risk of being exposed.

In view of these problems, this invention (j) has been developed to provide oil-retaining properties to the copper-thick aluminum alloy itself, and to prevent damage caused by oil depletion. Conventionally, in order to reduce local variations in the wear resistance of the alloy, the primary Si particles crystallized therein were made finer and distributed evenly. However, in this invention, the above-mentioned oil retention 111. is achieved by effectively utilizing coarse primary Si particles crystallized during the casting process. It has been a great success in encouraging them.

This invention includes 8112-30%, C110, 3-5%,
By melting and casting an aluminum-based alloy containing 0.3 to 2% M
A process of producing a ν1 block of primary crystal 3i particles in a range in which one particle occupies an area ratio of 50% or more, and hot-C extrusion of the ingot to form the Japanese primary crystal Si particles. The process of destroying and forming many small pores and the subsequent oil vapor]'-'1 (
)1. The gist is a method for manufacturing a wear-resistant aluminum alloy material A'1.

First, the significance of adding the above-mentioned alloy components and the reason for limiting the composition range will be explained as follows.

Sl is effective as a component for the well-known anti-wear resistance 111, and is also effective in this invention! It is useful for forming a large number of small pores by crystallizing primary St powder particles in 1:i and breaking one wave after 1:1. If the content is less than 12%, sufficient primary crystals S1 cannot be formed during casting. But 3
If the content exceeds 0%, casting becomes difficult.

Both Cu and Mg contribute to improving the strength of the alloy, and if the content is less than 0.3%, the effect is insufficient. However, when Cu exceeds 5%, -corrosion resistance deteriorates and the effects described in - are not particularly enhanced. Also, if MQ exceeds 2%, the above effects will be greatly increased! Rather, it generates crystallized substances and deteriorates mechanical properties.

In addition to the above-mentioned essential components, the aluminum alloy used in this invention preferably further contains N1, "e, Mn
γF may contain one or more types in the range of 0.5 to 3.0%, respectively. All of these components contribute to improving heat resistance, but each component
．． If it is less than 5%, the effect will be poor, and if it exceeds 3%, the machinability will be extremely poor.

Next, to describe the manufacturing process, the above aluminum alloy is first manufactured into a linofluminium alloy casting by hot-molten casting according to the conventional I;; method. However, during this casting process, no treatment for refining the primary Si crystals, such as the addition of elements effective for refining the primary crystals, shall be performed. Go to 10・
Contains primary Si particles of 200μ711, and has a particle size of 100~
2oo m primary crystal S i particle force 50% on IX (
1) It is said that it is crystallized and formed in a range that occupies the 1t'll fi°1 ratio. .

Therefore, next, the aluminum alloy casting containing the coarse primary crystal 3i particles was extruded at a temperature of about /120 to /130''C to obtain the desired aluminum-based alloy yield.

By the hot extrusion described above, the coarse primary 3i particles contained in the aluminum alloy are partially destroyed and reduced in size, thereby forming a large number of small pores of 10 to 50 μm in size.

These small holes act as oil reservoirs in the wear-resistant aluminum alloy material, resulting in a material with excellent oil retention properties.

Therefore, according to the present invention, the oil retaining property with a large number of small holes that function as oil reservoirs on the surface is achieved by a simple two-step process of melting and casting an aluminum alloy and hot extrusion. It is possible to obtain a +6'i red-resistant aluminum alloy material, and as a material for forming sliding surfaces, J3 has less damage to sliding surfaces due to lack of oil.
PI wear-resistant 4A slope with better performance than conventional products.
simple! li! It has the advantage of being able to be provided at a relatively low cost in the I-build process.

Examples of the present invention will be shown below.
They were first melted and cast, and the billets 1 to 120 mm in diameter were made.
was manufactured. During this ijj manufacturing, the primary crystal S1 was not refined. However, the particle size of the primary Si particles contained in the billet is in the range of 10-200 μm, and is in the range of 100-20 μm.
Coarse grains of 0μ71L accounted for at least 50% of the surface (knee ratio), and on the other hand, the grain size of the same product 51tj37 particles was in the range of 30μ711 or less.

Next, this billet was extruded under the conditions of extrusion temperature of 425°C and extrusion ram speed of 0.04 m/min. :″ Core diameter 30
Extruded into a mtn round bar, the expected monthly yield of J)l aluminum alloy is 111.

When the microstructures of the various aluminum alloys obtained were examined, it was found that the coarse primary Si particles were destroyed and the particle size was refined to within a range of 10 to 100μ7n, and Many small pores of 10 to 50 μm were formed due to the destruction of the coarse original Si particles. This confirmed that it was responsible for the excellent oil retention properties. In addition, the eutectic Si particles are also refined to a particle size of 20 μm or less, and together with the miniaturization and uniform distribution of the primary 3i particles, the i
It was confirmed that the wear resistance of l+41fj was excellent after one summer and there was little local variation.

that's all

Claims (1)

[Claims] 8112-30%, Cu 0.3-5%, MgO, 3-30%
Melt an aluminum-based alloy containing 2% 1'i'i! Cast to a particle size of 100-200 μm17. coarse primary crystal 3
A box in which the i-particles occupy a surface l1ri ratio of 50% or more [11 steps of forming a primary Si particle group 6/J block, hot extruding the ingot, M41', which also improves oil retention by breaking the primary crystal S1 particles and forming a large number of small pores;