JPH0281989A - Compressor-use cylinder having molybdenum explosion bonding covered layer - Google Patents

Abstract

PURPOSE:To obtain the lightness of weight further with excellent wear resistance by providing a metal molybdenum explosion bonding covered layer of specific thickness in the internal surface of a member molded in a cylinder shape by an aluminum alloy of specific composition. CONSTITUTION:Constitution of this cylinder 3 is such that an explosion bonding covered layer of 30 to 200mum thickness, consisting of metal molybdenum, is provided in internal surfaces of a member molded in a cylindrical shape by an aluminum alloy composed of 5 to 25% silicone, 0.3 to 5% copper, 0.3 to 3% magnesium and the rest of aluminum by the reference of weight as the essential component. Then, of these components, action of the silicone improves wear resistance and decreases a coefficient of linear expansion, and action of the copper improves wear resistance and high temperature strength. While action of the magnesium, similar to the copper, improves the wear resistance and the high temperature strength. And the molybdenum, forming the covered layer by explosion bonding, uses metal single substance molybdenum. Thus, the cylinder 3 for use of a compressor enables even its weight to be reduced with sufficient durability.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a compressor cylinder, and particularly to a compressor cylinder with excellent wear resistance.

[Prior Art] Rotary vane type cooler compressors are widely used, and the components other than the vanes are made of iron.

However, since there is a strong demand for car coolers to be lightweight, it has been proposed to manufacture them from aluminum alloys, but it has been difficult to put them into practical use because they do not have sufficient wear resistance.

[Problems to be Solved by the Invention] It is an object of the present invention to provide a cylinder for a compressor that has a structure that is particularly lightweight and has excellent wear resistance.

[Means for Solving the Problems] The configuration of the present invention for solving the above problem 1 is as follows! Based on li content, essential components include silicon 5-25% and copper 0.3-25%.
5% magnesium, 0.3 to 3% magnesium, and the balance aluminum, and the compressor is characterized by having an explosion-bond coating layer of 30 to 200 μ-thick made of metallic molybdenum on the inner surface of a member formed into a cylindrical shape. and a cylinder for a compressor, characterized in that the aluminum alloy further contains one or more of 1 to 9% of nickel and 0.3 to 3% of manganese in addition to the above metal components.

Regarding the components of the aluminum alloy used in the present invention, silicon acts to improve wear resistance and lower the linear expansion pressure ratio, and the required amount is 5 to 25%.

If it is less than 5%, wear resistance is insufficient, and if it exceeds 25%, extrusion becomes difficult.

However, the appropriate silicon content is 5 for foundry alloys.
~10%, l for extruded profile alloys.

-17% In the case of powdered gold powder, 12-25% is suitable.

The action of copper is to improve wear resistance and high temperature strength, and if the amount is less than 1%, the effect is insufficient, and if the amount is less than 1%, the effect is insufficient.
If it exceeds this value, the effect will be saturated and the performance will not improve.

Like steel, the effect of magnium is to improve wear resistance and high-temperature strength. If the amount is less than 0.3%, the effect is insufficient, and if it exceeds 3%, the effect is saturated.

The effect of nickel is to reduce the coefficient of linear expansion and improve high-temperature strength. If the amount is less than 1%, the effect is insufficient, and if it exceeds 9%, hot workability becomes difficult.

The effect of manganese is to improve heat resistance and high-temperature strength, and if the amount is less than 0.3%, the effect is insufficient, and if it exceeds 3%, the effect is saturated.

The molybdenum forming the coating layer by explosion bonding is an elemental metal molybdenum, and the layer thickness is 30 to 200 μm.

If the layer thickness is less than 30 μm, seizure will occur and the wear resistance will be insufficient. Even if it exceeds 200μ, no further effect can be obtained and the manufacturing cost increases.

In this explosive bonding method for molybdenum coating layers, a metal MO wire is placed in the center of the cylinder, high voltage and high current are momentarily applied to cause explosive bonding, and the surface is then smoothed.

An example of the structure of the above compressor will be explained with reference to a rotary vane type car cooler compressor shown in the drawings. A rotor 2 having vanes 1 is provided in a cylinder 3. As the rotor 2 rotates, refrigerant is sucked, Pressurized refrigerant is discharged.

The properties required for this cylinder are: (1) A small coefficient of linear expansion (15 to 22X10'c
m/°C), (2) no seizure with vanes and excellent wear resistance, (3) excellent productivity, etc.

The material of the cylinder is an aluminum alloy containing 5 to 25% silicon, for example, AI-4%Cu-0.4%
There is a Mg-17%5i-2%Ni alloy.

Using this material, a molten metal forging method with less porosity and shrinkage rate,
Alternatively, molybdenum is coated on the inner surface of a cylinder cast by vacuum die-casting or an extruded cylinder by explosive bonding.

The characteristics of this coating method by explosive bonding are as follows: (1) The thickness of the coating layer can be freely selected, for example, 3
It is possible to form a coating layer with a thickness of about 0 μm to a thickness of about 200 μm.

(2) Explosion bonding is completed instantaneously, so productivity is extremely high.

(3) A coating layer formed by explosive adhesion has stronger adhesion to the base material than a coating layer formed by plating or painting.

[Examples] The present invention will be specifically explained below using Examples and Comparative Examples.

Disks were prepared by forming molybdenum layers of slightly different thickness on disk members manufactured using the aluminum alloys shown in Table 1 by explosive bonding, and the disks were tested.

In the first table baking test, a powder alloy pin was pressed against the outer periphery of the above-mentioned disk with a diameter of 60+mm with a surface pressure of 50 kgr/am'', and the disk was rotated for 30 minutes at a speed of 1000 mm/sec at the contact area between the bottle and the disk. This was done by checking for the presence or absence of burn-in.

The wear resistance test is similar to the seizure test, but with the addition of lubricating oil (
The samples were immersed in Suniso Oil 5GS (manufactured by Nippon Sun Oil Co., Ltd.) at 70° C., and those with no visible wear were evaluated as good.

Table 2 below shows the relationship between the presence or absence of an explosive coating layer made of molybdenum, the thickness of the coating layer, and the test results.

Table 2 *20 is good × is bad [Effects of the invention] As explained above, the compressor cylinder of the present invention has sufficient durability and uses aluminum alloy, so it is compared with conventional cylinders. It is also possible to reduce heavy engineering by about 50%.

[Brief explanation of the drawing]

The drawing is a schematic cross-sectional view for explaining the structure of a rotary vane type car cooler compressor using the cylinder of the present invention. l... Vane, 2... Rotor 3... Cylinder. * Existence is burned in, non-existence is not burned in.

Claims (2)

[Claims] (1) The inner surface of a member formed into a cylindrical shape from an aluminum alloy consisting of 5 to 25% silicon, 0.3 to 5% copper, 0.3 to 3% magnesium, and the remainder aluminum on a weight basis is made of metal molybdenum with a thickness of 30 to 30%. A cylinder for a compressor, characterized in that it has an explosive bonding coating layer of 200μ. (2) The cylinder for a compressor according to claim 1, wherein the aluminum alloy further contains one or more of 1 to 9% nickel and 0.3 to 3% manganese on a weight basis.