TW201326414A - White metal babbitt for rolling mill bushing - Google Patents

Abstract

A tin based white metal alloy consisting essentially by weight of approximately 5.0%-9.0% antimony, approximately 3.0%-8.0% copper, approximately 0.1%-0.7% cobalt, and the balance tin.

Description

White metal babbitt for rolling mill bushing

This application is based on 35 U.S.C. § 119(e), which is entitled to the benefit of the benefit of the benefit of the benefit of the benefit of the benefit of the benefit of the benefit.

Embodiments of the present invention and aspects relate to tin-based white metal alloys that can be used in a variety of different industrial applications, including bushings for roll oil film bearings.

Among the oil film bearings in the field of the rolling mill, the most prominent white metal alloy used is described in ASTM B23 #2 (hereinafter referred to as ASTM #2), and is mainly composed of tin and an element in which bismuth and copper are alloyed. ASTM #2 is well known and can be easily deposited onto bushings by centrifugal casting, spray forming or welding. Unfortunately, ASTM #2 has a relatively low fatigue resistance, which limits the load capacity of bearings made from this material.

Variants of various nickel hardened white metal alloys have been used, and a commonly used variant is called Tuftin. These alloys can be cast and welded, but they contain nickel, which is a heavy metal that is undesirable based on environmental considerations.

No. 6,589,372 B1 (Roeingh et al.) teaches the use of known tin-based white metal alloys which consist essentially of tantalum, copper, zinc, silver and tin.

Roeingh alloys are suitable for centrifugal casting applications. But due to the brittleness of the zinc component. This alloy is difficult to pull into the metal needed for spray coating and welding applications. line.

U.S. Patent No. 4,140,835 (Goddard) and U.S. Patent Application Serial No. 2,146,354, the disclosure of which is incorporated herein by reference. Cadmium is known to be a carcinogen and most workplaces are banned, so it is not a good choice.

Alloys are proposed in U.S. Patent Nos. 4,150,983 (Mori) and 5,512,242 (Tanake et al.), in which cobalt is used with chromium. The inclusion of chromium metal is not practical and it does not dissolve easily under normal alloying conditions.

No. 4,795,682 (Turner et al.) discloses a tin/cobalt alloy which can be used as a sacrificial coating designed to absorb particulates. Such coatings lack the toughness required for high load oil film bearing applications, and the proposed cobalt content is a high percentage which will inhibit the flow characteristics necessary in the casting or welding process.

Briefly, the present invention is directed to tin-based white metal alloys that can be used in centrifugal casting, spray coating, and welding applications.

The present invention is also directed to tin-based white metal alloys having high strength and fatigue resistance required for high load oil film bearings commonly found in the metal industry.

The present invention is further directed to a low toxicity tin-based white metal alloy, and generally does not contain carcinogenic components including cadmium.

In one embodiment, the present invention can be substituted for the zinc and silver components of the alloy disclosed in the previously cited U.S. Patent No. 6,589,372 B1 by the amount of cobalt between about 0.1% and 0.7% by weight. The optimum amount is between 0.2% by weight and 0.5% by weight.

In order to facilitate the understanding of the embodiments, principles, and features of the present invention, the following description will be explained with reference to the embodiments of the illustrative embodiments. In particular, it will be described in the context of a novel and non-obvious tin-based white metal alloy.

However, embodiments of the invention are not limited to the described system.

The ingredients and materials used to form the various embodiments are described as illustrative and not limiting. Many suitable ingredients and materials that exhibit the same or similar function as the materials described herein are included within the scope of embodiments of the invention.

The tin-based white metal alloy of the present invention comprises tin, bismuth and copper as main components, among which cobalt is incorporated. When the amount of cobalt added is more than about 0.7% by weight, it has been found that the fluidity of the resulting alloy is lowered to cause a bad influence. Accordingly, the amount of cobalt added is preferably between about 0.1% and 0.7% by weight, which has been found to be effective for the above purposes, with an optimum of between about 0.2% and 0.5% by weight.

The tin-based white metal alloy of the present invention is essentially composed of the components listed in the following examples:

Example I

锑 5.0-9.0% by weight

Copper 3.0-8.0% by weight

Cobalt 0.1-0.7% by weight

Tin residual difference

Example II

锑 6.0-8.0% by weight

Copper 3.0-8.0% by weight

Cobalt 0.1-0.7% by weight

Tin residual difference

Example III

锑 6.0-8.0% by weight

Copper 6.0-7.0% by weight

Cobalt 0.1-0.7% by weight

Tin residual difference

Example IV

锑 6.0-8.0% by weight

Copper 6.0-7.0% by weight

Cobalt 0.2-0.5% by weight

Tin residual difference

Example V

锑 6.0-8.0% by weight

Copper 6.0-7.0% by weight

Cobalt 0.2-0.5% by weight

Tin residual difference

The alloys obtained in the present invention can be centrifugally cast and can be drawn into the metal wires required for spray coating or welding applications. In addition, the alloys of the present invention have the strength and fatigue resistance required for high load bearing applications, including in the steel industry, and do not contain banned or otherwise hazardous ingredients.

The fatigue resistance of white metal alloys can be determined by experiments using periodic stretching/compression until sample failure. The results of the comparison of the laboratory test data of the alloy of the present invention with the alloys commonly used in the art are shown in Table 1. From the test data, it is known that the fatigue strength of an alloy containing 0.3% by weight to 0.5% by weight of cobalt has excellent fatigue resistance, surpassing other alloys commonly used in the field of rolling mill applications. The test data shown is determined in accordance with ASTM E 466 at a load of 7,500 psi (51.7 MPa) and a test frequency of 10 Hz.

While the embodiments of the present invention have been disclosed by way of illustration, it will be apparent to those skilled in the art Such as As described in the scope of the following patent application.

Claims (10)

A tin-based white metal alloy comprising essentially from about 5.0% to about 9.0% by weight bismuth, from about 3.0% to about 8.0% by weight copper, from about 0.1% to about 0.7% by weight cobalt, and the balance being tin . An alloy according to claim 1, wherein the content of cerium is from about 6.0% by weight to about 8.0% by weight. An alloy according to claim 1, wherein the copper content is from about 6.0% by weight to about 7.0% by weight. An alloy according to claim 1, wherein the cobalt is present in an amount of from about 0.2% by weight to about 0.5% by weight. For example, the alloy of the first application of the patent scope is applicable to high load bearings for the steel industry. For example, the alloy of claim 1 is applicable to high load bearings for power generation equipment. For example, the alloy of the first application of the patent scope is suitable for the bearing of spray coating and welding. For example, the alloy of claim 1 is suitable for cast-formed babbitt type bearings. A tin-based white metal alloy comprising essentially from about 6.0% to about 8.0% by weight bismuth, from about 6.0% to about 7.0% by weight copper, from about 0.2% to about 0.5% by weight cobalt, and the balance being tin . For example, the alloy of claim 9 is applicable to at least one of the following: high load bearing for steel industry; high load bearing for power generation equipment; spray coated and welded bearing; or cast molded Papillon Alloy bearing.