JPS582578B2 - aluminum bearing alloy - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an aluminum-zinc (Zn) bearing material having aluminum (Al) as a base material.

More specifically, Al-Z, which has excellent wear resistance and fatigue resistance, is made by dispersing a large amount of hard material in an Al-Zn bearing alloy.
An object of the present invention is to provide an n-type bearing alloy.

Aluminum-tin (Sn) alloys are mainly used as conventional aluminum bearing alloys, but as modern automobile fuel engines are used at higher speeds and under higher load conditions, this alloy has become more difficult to bond with shafts and bearings. This is due to the thinning of the lubricating oil film intervening between the shaft and bearing, resulting in direct contact between the shaft and bearing.
Abrasion and seizure often occurred.

Therefore, the present invention uses Al-Z, which has sufficient wear resistance even when the shaft and bearing come into direct contact, and also has excellent fatigue resistance.
An object of the present invention is to provide an n-type bearing alloy.

That is, Zn0.5~ by weight with Al as the substantial remainder.
less than 3%, silicon (Si) 0.05 to less than 2%, lead (
pb) and/or indium (In) 0.1-5
%, antimony (Sb), nickel (Ni), iron (Fe
), chromium (Cr), titanium (Ti), zirconium (
A bearing base metal (alloy) l comprising one or more of Zr), molybdenum (Mo), cobalt (Co), tungsten (W), and vanadium (V) in a total content of more than 0.8 and less than 5%.

Alloy 1 contains copper (Cu) and/or magnesium (M
The present invention provides a bearing alloy (alloy 2) containing 0.1 to 2% of g).

Next, the characteristics of various elements added to this alloy are Zn:
A solid solution or an Al-Zn solid solution is dispersed in the Al base to provide appropriate lubricity and wear resistance.

If it is less than 0.5%, Zn has almost no effect, and if it is more than 3%, the load-bearing property decreases.

Si: Hard enough to show 600 or more on the Vickers hardness, Al
By casting with aluminum, crystallized substances are dispersed, which improves the hardness of the entire alloy, strengthens the Al base, and improves wear resistance.

If it is less than 0.05%, it is ineffective, and if it is more than 2%, the mating shaft will wear more due to the hardness of Si.

pb, ■n: Provides particularly non-seizure properties among slip properties, resulting in a material with excellent slip properties.

It also has excellent machinability and facilitates post-processing.

If it is less than 0.1, there will be no above effect, and if it exceeds 5%, it will be A.
Uniform dispersion over the ground becomes difficult due to weight segregation.

Cu, Mg: Strengthens the Al base in terms of load resistance and fatigue strength, and prevents a large decrease in hardness when the bearing is exposed to high temperatures (200°C or higher).

If it is less than 0.1%, there is no effect, and if it exceeds 2%, the Al base becomes too hard and brittle.

Sb, Ni, Fe, Cr, Ti, Zr, Mo, Co, W
,■: By casting these elements together with Al (generally added in the master alloy), precipitates etc. are generated, and since these are all hard substances (Vickers hardness of several hundred or more), the hardness of the entire alloy and strengthens the aluminum base and improves wear resistance.

However, since these have lower hardness than Si, the same amount cannot produce the same effect as Si.

Therefore, by dispersing the above-mentioned precipitates, which have a slightly lower hardness, around the hard Si, it is possible to improve the wear resistance and hardness as a whole and strengthen the Al base.

If it is less than 0.8%, there is no effect, and if it exceeds 5%, there will be too much hard dispersion and it will become brittle.

The preferred ranges here are: Zn: 1-2.5% Pb, In: 0.5-5% Si
: 0.5 or more Cu, Mg: 0.7 to 1.5% Sb, etc.: 1.0 to 4.0%.

Next, the present invention will be explained by examples.

The following table shows the chemical component values of test subjects (1) to (12) according to the present invention and (13) to (15) as comparative examples.

Alloys (1) to (12) are produced by melting Al base metal in a gas furnace, and then melting Al-Sb master alloy, Al-Cu master alloy, and A
l-Mg master alloy, Al-Si master alloy, Al-Ni master alloy, Al-Ti master alloy, Al-Fe master alloy, Al-Zr master alloy, Al-Co master alloy, etc. are melted according to the target components. Finally, Zn, Pb, In, etc. are added, followed by degassing treatment, casting into a mold, and then rolling and annealing (3
50° C.) to prepare samples and measure their hardness.

Next, this sample was further rolled, and then these alloys and a backing steel plate were bonded to form a bimetallic material, which was annealed and processed into a flat bearing, and a friction test was conducted.

For alloys (13) to (15), comparative alloys were prepared using the same manufacturing method as the above-mentioned alloys and used as samples, and the same tests were conducted.

Table 1 shows the results of measuring the hardness of the above alloys (1) to (15) using Witzkers hardness.

As is clear from these graphs, (1
) to (12) all have hardness equivalent to or higher than comparative alloys (13) to (15).

This is due to hard substances such as Si and precipitates.

In particular, alloys to which Cu and/or Mg are added,
It has been found that when hardness is measured at elevated temperatures, the decrease in hardness is small even at high temperatures.

This means that the bearing has load resistance and wear resistance even when used at high temperatures.

Next, FIG. 1 shows alloys (3), (7), and (9) according to the present invention.
), (11) and comparative alloys (13), (14), (1
5) shows the results of a friction test.

In this experiment, the shaft rotation speed was 1000 r. p. m, S55C hardened material is used as the shaft material, and the shaft surface roughness is 1 μm.
It is a graph showing the results of measuring the state of wear loss when the load is increased under forced lubrication at a constant oil temperature (120° C.).

According to this graph, comparative alloys (13), (14),
Compared to (15), (3), (7), (9), and (11) were found to have extremely small amounts of wear, indicating excellent wear resistance.

It is recognized that this is an effect of hard materials dispersed in the Al ground.

In addition, in the alloy composition according to the present invention, it goes without saying that Al contains impurities that cannot be avoided by ordinary refining techniques.

As described above, the Al-Zn bearing alloy according to the present invention contains Zn
For high-load applications, it has moderate lubricity due to the use of Pb and In, wear resistance due to hard materials such as Si and SB, fatigue resistance due to the synergistic effect of these, and improved conformability and seizure resistance due to Pb and In. Bearing alloy.

[Brief Description of the Drawings] Fig. 1 is a graph showing changes in the amount of wear when a load is applied.

Claims (1)

[Claims] 1. Zn 0.5 to less than 3%, Si 0.05 to 2% by weight
less than PB and/or In 0.1-5%, Sb,
An aluminum bearing alloy containing one or more of Ni, Fe, Cr, Ti, Zr, Mo, Co, W, (2) in an amount of more than 0.8% and less than 5%, and the balance being substantially Al. 2 Zn 0.5 to less than 3%, Si 0.05 to 2% by weight
less than pb and/or In 0.1-5%, Cu and/or Mg 0.1-2%, Sb, Mi, Fe,
One or two of Cr, Ti, Zr, Mo, Co, W, V
An aluminum bearing alloy consisting of a total of more than 0.8% and less than 5%, and the balance is substantially Al.