Friction-resistant alloy for use as a bearing

Abstract

A friction-resistant alloy being a tin matrix containing copper, antimony, and between about 0.10% and about 2% by weight bismuth; and an industrial bearing component having this alloy on a wear surface.

Description

BACKGROUND OF THE INVENTION

[0001] This invention relates to a friction-resistant alloy for use as a bearing.

[0002] When a lubricant film cannot completely separate rubbing surfaces of a bearing, friction and wear increase. The resulting frictional heat combined with high pressure promotes localized welding of the two rubbing surfaces. Welded contact points form which break apart with relative motion and metal is pulled from one or both surfaces decreasing the life of the bearing. This friction and welding is most common when like metals, such as steel or cast iron, are used as bearings. Compatibility of bearing materials, therefore, and absorption of lubricant upon the bearing surface, is necessary to reduce metallic contact and extend bearing life.

[0003] In the 19th century Isaac Babbitt formulated a white metal alloy that showed excellent bearing properties. Since then, the name “babbitt” has been used for other alloys involving similar ingredients. Babbitts offer an almost unsurpassed combination of compatibility, conformability, and embedability. They easily adapt their shapes to conform to the bearing shaft and will hold a lubricant film. Foreign matter not carried away by the lubrication is embedded below the surface and rendered harmless. These characteristics are due to babbitts' hard/soft composition. ASTM B-32 presents a class of tinbased babbitts. High-tin babbitts consist of a relatively soft, solid matrix of tin in which are distributed hard copper-tin needles and tin-antimony cuboids. This provides for “good run-in,” which means the bearing will absorb a lubricant on the surface and hold the lubricant film. Even under severe operating conditions, where high loads, fatigue problems, or high temperatures dictate the use of stronger materials, babbitts are often employed as a thin surface coating to obtain the advantages of their good rubbing characteristics.

[0004] Many babbitts have historically included lead. This use of lead, however, presents toxicity concerns.

[0005] U.S. Pat. No. 5,705,126 discloses a bearing alloy consisting of 6 to 15% antimony, 3 to 10% copper, 0.05 to 1% silver, and 0.1 to 2% zinc, all by weight, with the remainder being tin. The use of silver, however, presents concerns with regard to the cost of the alloy. Also, the use of zinc presents concerns with regard to excessive drossing and castability during manufacturing.

[0006] The '126 patent also discloses a prior art bearing alloy having 12% antimony, 5.5% copper, 1.2% cadmium, 0.3% nickel, and 0.5% arsenic, with the remainder being tin. Cadmium and arsenic, however, are toxic. And the use of nickel is disadvantageous because of the difficulty to melt and hold nickel in solution prior to casting into final form.

SUMMARY OF THE INVENTION

[0007] It is an object of this invention, therefore, to provide a friction-resistant alloy for use as a bearing which specifically excludes intentional additions of silver, zinc, cadmium, arsenic, nickel, and lead; to provide a friction-resistant alloy for use as a bearing having improved resistance to creep rupture at elevated temperatures; and to provide a friction-resistant alloy for use as a bearing comprising bismuth to enhance resistance to creep rupture at elevated temperatures.

[0008] Briefly, therefore, the invention is directed to an alloy and to an industrial bearing component with the alloy thereon. The friction-resistant alloy is a tin matrix containing copper, antimony, and bismuth in an amount between about 0.10% and about 2% by weight.

[0009] Other objects and feature will be in part apparent and in part pointed out hereinafter.

DETAILED DESCRIPTION OF THE INVENTION

[0010] The alloy of the invention is a friction-resistant alloy being a tin matrix containing Cu, Sb, and between about 0.10% and about 2% by weight Bi. All percentages presented herein are by weight. The major constituent of the alloy is Sn. The Sn content of the alloy is preferably in the range of about 73 wt % to about 97 wt %. Tin is relatively soft, which provides lubrication to bearing surfaces, and facilitates application by spraying, welding, or other techniques. The tin matrix has excellent corrosion resistance, easy bonding, and a low tendency for segregation and welding in service.

[0011] In formulating the alloy of the invention, antimony is employed because it forms relatively hard tin-antimony cuboids. These cuboids improve the strength characteristics of the alloy and facilitate absorption and maintenance of a lubricant film at the surface. The concentration of antimony is from about 3 to about 15%. If insufficient antimony is employed, the alloy will have insufficient load-bearing capacity. If too much antimony is employed, the alloy may embrittle. In certain preferred embodiments, antimony is between about 3 and about 6%, and in other preferred embodiments it is between about 6 and about 9%, and in still others between about 7 and about 9%.

[0012] Copper is employed to form copper-tin needles, which adds hardness to the relatively soft tin matrix. These needles facilitate absorption and maintenance of lubricant film at the surface. The concentration of copper is at least about 0.5% or 1%. It is no greater than about 10%. In certain preferred embodiments, copper is between about 3 and 6%, in others between about 7 and 9%, and in still others between about 2 and about 5%. If too much copper is employed, the alloy is embrittled. If insufficient copper is employed, the alloy has insufficient load-bearing capability.

[0013] Bismuth is employed in the alloys, as it has been discovered to provide enhanced creep properties and high temperature strength at service temperatures exceeding 160° F., and in the range of from room temperature to about 250° F. The bismuth is a fine precipitate at room temperature, and is in solution within the tin matrix at these service temperatures. The concentration of bismuth is at least about 0.1%. If insufficient bismuth is employed, the alloy will have decreased high temperature strength and creep life. In certain preferred embodiments, bismuth is at least about 0.1%, and in other preferred embodiments at least about 0.25%. The concentration of bismuth is no more than about 2%.

[0014] The alloy is preferably Pb-free, Cd-free, As-free, Ni-free, Ag-free, and Zn-free, meaning that there are no intentional additions of lead, cadmium, arsenic, nickel, silver and zinc. The use of scrap in formulating the alloys, however, indicates that these and other tramp elements may be found in the alloys in trace amounts. The overall trace elemental composition is preferably maintained below about 0.75%. The trace elemental composition of each of lead, cadmium, nickel, arsenic, silver and zinc is individually held below 0.35%, preferably below about 0.1%.

[0015] There is an alternative embodiment specifically formulated for higher service temperatures in the range of about 160° F. This embodiment is Pb-free, Cd-free, As-free, Ag-free, and Zn-free. This embodiment optionally includes intentional additions of Ni on the order of about 0.1 wt % to about 0.5 wt % for high temperature service enhancement.

[0016] Among the preferred compositions for the alloy are the following:

[0017] Sb 3 to 15%

[0018] Cu 0.5 to 10%

[0019] Bi 0.1 to 2%

[0020] Sn remainder

[0021] plus incidental impurities.

[0022] Sb 3 to 6%

[0023] Cu 3 to 6%

[0024] Bi 0.1 to 2%

[0025] Sn remainder

[0026] plus incidental impurities.

[0027] Sb 7 to 9%

[0028] Cu 7 to 9%

[0029] Bi 0.25 to 2%

[0030] Sn remainder

[0031] plus incidental impurities.

[0032] And

[0033] Sb 6 to 9%

[0034] Cu 2 to 5%

[0035] Bi 0.25 to 2%

[0036] Sn remainder

[0037] plus incidental impurities.

[0038] Variations of these include formulations which have from about 0.1% to about 0.5% Ni, as well as formulations which are specifically Pb-free, Cd-free, and As-free; formulations which are specifically Ni-free, Ag-free, and Zn-free; formulations which are specifically Ag-free and Zn-free; and formulations combining certain of these requirements.

[0039] The physical form of the alloy is cast, in bars, wire, or in powder, as best suited for the particular method to be employed in applying the alloy to particular bearing surfaces.

[0040] In forming the alloys, the starting materials are in virgin raw material or recycle scrap form. Controlled melting procedures are employed involving gas, electrical resistive, or induction sources dissolving the higher melting constituents into a tin bath.

EXAMPLE 1

[0041] A sample was prepared by melting a virgin charge of tin, copper, antimony, and bismuth into an electrical resistance heated cast iron pot. The melt charge was of the following composition:

[0042] 7.3% Sb

[0043] 3.7% Cu

[0044] 1.5% Bi

[0045] Balance Sn

[0046] The molten metal was cast into a water-cooled steel test bar mold (0.75 inches in diameter by 4.5 inches in length).

EXAMPLE 2

[0047] Compression stress and tensile strength tests were performed according to the procedures of ASTM E9-89a and E8-00 respectively. These tests compared the properties of the alloy of the invention in Example 1 to a Grade 2 babbitt alloy having a specification composition range as follows:

[0048] 7-8% Sb

[0049] 3-4% Cu

[0050] 0.08% Bi max

[0051] 0.35% Pb max

[0052] 0.1% As max

[0053] 0.08% Fe max

[0054] 0.005% Zn max

[0055] 0.005% Al max

[0056] 0.05% Cd max

[0057] 88-90% Sn

[0058] The results of the two tests are presented in Tables 1 and 2A-B respectively, with the alloy of the invention designated N and the Grade 2 babbitt alloy designated 2. The compression test results reveal a 40% increase in the load bearing capacity at room temperatures for the alloy. The tensile test results reveal an improvement in room-temperature UTS, yield strength, and ultimate load of greater than 10%.

TABLE 1
Results of Compression Stress Test
				Ultimate
Bar	Sample	Temp.	UTS	Load	Orig. Dia.	Original Area
ID	ID	(EF)	(ksi)	(lbs)	(in)	(in2)
2	C1	Room	13.3	2608	0.5004	0.19666383
N	C1	Room	19.6	3849	0.5004	0.19666383

[0059]

TABLE 2A
Results of Tensile Test
				0.125%			Modu-	Ult.
Bar	Sample	Temp.	UTS	YS	Elong	RA	lus	Load
ID	ID	(EF)	(ksi)	(ksi)	(%)	(%)	(MSI)	(lbs)
2	1	Room	10.5	7.4	18	26	5.7	1044
N	1	Room	12.6	8.7	11	12	7.0	1254

[0060]

TABLE 2B
Results of Tensile Test (cont.)
					4D
		Orig.	Final	4D Orig	Final
Bar	Sample	Dia.	Dia.	GL	GL	Orig. Area
ID	ID	(in)	(in)	(in)	(in)	(in2)
2	1	0.3557	0.3050	1.40	1.65	0.09937052
N	1	0.3560	0.3339	1.40	1.55	0.09953823

EXAMPLE 3

[0061] Compression stress and tensile strength tests were performed according to the procedures of ASTM E9-89a and E21-92 respectively. These tests examined the characteristics of test bars prepared according to the invention as described in Example 1 (sample N) versus the Grade 2 babbitt alloy of Example 2 (designated 2). A thirty minute soak at the test temperature was performed prior to each test. The results of the two tests are presented in Tables 3 and 4A-B respectively. The compression test results show a 30% increase in load bearing capacity at 160° F. The tensile test results show an improvement in elevated-temperature (160° F.) UTS and yield strength of greater than 20%.

TABLE 3
Results of Compression Stress Test
				Ultimate
Bar	Sample	Temp.	UTS	Load	Orig. Dia.	Original Area
ID	ID	(EF)	(ksi)	(lbs)	(in)	(in2)
2	C2	160	8.6	1111	0.4058	0.12933438
N	C2	160	11.9	2348	0.5004	0.19666383

[0062]

TABLE 4A
Results of Tensile Test
				0.125%			Modu-	Ult.
Bar	Sample	Temp.	UTS	YS	Elong	RA	lus	Load
ID	ID	(EF)	(ksi)	(ksi)	(%)	(%)	(MSI)	(lbs)
2	2	160	7.0	5.6	28.5	34.5	5.5	696
N	2	160	9.2	7.3	10.0	12.0	6.6	909

[0063]

TABLE 4B
Results of Tensile Test (cont.)
					4D
		Orig.	Final	4D Orig	Final
Bar	Sample	Dia.	Dia.	GL	GL	Orig. Area
ID	ID	(in)	(in)	(in)	(in)	(in2)
2	2	0.3556	0.2875	1.40	1.80	0.09931467
N	2	0.3556	0.3337	1.40	1.54	0.09931467

EXAMPLE 4

[0064] Compression stress and tensile strength tests were performed according to the procedures of ASTM E9-89a and E21-92 respectively. These tests examined the characteristics of the alloy of the invention of Example 1 (designated N) versus the Grade 2 babbitt alloy of Example 2 (designated 2). A thirty minute soak at the test temperature was performed prior to each test. The results of the two tests are presented in Tables 5 and 6A-B respectively. The compression test results show an improvement in load bearing capacity at 250° F. The tensile test results show an improvement in elevated temperature (250° F.) UTS and yield strength of greater than 20%.

TABLE 5
Results of Compression Stress Test
				Ultimate
Bar	Sample	Temp.	UTS	Load	Orig. Dia.	Original Area
ID	ID	(EF)	(ksi)	(lbs)	(in.)	(in2)
2	C3	250	6.0	1058	0.4738	0.17631124
N	C3	250	7.1	1400	0.5009	0.19705701

[0065]

TABLE 6A
Results of Tensile Test
				0.125%			Modu-	Ult.
Bar	Sample	Temp.	UTS	YS	Elong	RA	lus	Load
ID	ID	(EF)	(ksi)	(ksi)	(%)	(%)	(MSI)	(lbs)
2	3	250	4.4	3.4	40.5	55.5	4.9	435
N	3	250	5.6	4.3	10.0	12.0	5.2	559

[0066]

TABLE 6B
Results of Tensile Test (cont.)
					4D
		Orig.	Final	4D Orig	Final
Bar	Sample	Dia.	Dia.	GL	GL	Orig. Area
ID	ID	(in)	(in)	(in)	(in)	(in2)
2	3	0.3545	0.2370	1.40	1.97	0.09870118
N	3	0.3556	0.3335	1.40	1.54	0.09931467

EXAMPLE 5

[0067] Creep tests were performed according to the procedures of ASTM E139-96. These tests examined the characteristics of the alloy of the invention of Example 1 (designated N) versus the Grade 2 babbitt alloy of Example 2 (designated 2). A sixty minute soak at the test temperature was performed prior to each test. The results of the tests are presented in Tables 7A-B. The tests show an improvement in time to rupture at both room temperature and elevated temperature (160° F.), with the improvement at elevated temperature being greater than 150%. It is evident that the alloy has a time to elevated temperature creep rupture of at least about 100 hours when tested at 160° F. and in accordance with procedures of ASTM E139-96.

TABLE 7A
Results of Tensile Creep Tests
			Rupture			Total	Pan
Bar	Sample	Temp.	Time	Elong	RA	Creep	Load
ID	ID	(EF)	(hrs)	(%)	(%)	(%)	(lbs)
2	S1	76	1332.2*	19.0	20.9	6.3	10.9
2	S2	160	64.9	9.0	16.9	6.35	10.9
N	S1	76	1397.4*	8.0	7.8	7.5	10.8
N	S2	160	173.9	27.0	30.2	5.1	10.8
*Upload: 500 PSI every 12 hrs after 1276 hrs.

[0068]

TABLE 7B
Results of Tensile Creep Tests (cont.)
			Orig.	Final	Eff.	Orig.	Final
Bar	Sample	Stress	Dia.	Dia.	GL	GL	GL
ID	ID	(ksi)	(in)	(in)	(in)	(in)	(in)
2	S1	3.5	.2516	.2237	1.3360	1.00	1.19
2	S2	3.5	.2517	.2294	1.3320	1.00	1.09
N	S1	3.5	.2508	.2408	1.3350	1.00	1.08
N	S2	3.5	.2507	.2095	1.3365	1.00	1.27

[0069] The ASTM specifications under which the tests were conducted are submitted as Appendices.

[0070] The foregoing relates to a limited number of embodiments that have been provided for illustration purposes only. It is intended that the scope of invention is defined by the appended claims and there are modifications of the above embodiments that do not depart from the scope of the invention.

Claims

1. An industrial bearing component comprising: a substrate having a wear surface; and a friction-resistant alloy on the wear surface, the alloy being a tin matrix containing copper, antimony, and between about 0.10% and about 2% by weight bismuth.

2. The industrial bearing component of claim 1 wherein the friction-resistant alloy comprises, by approximate weight %: Sb 3 to 15% Cu 0.5 to 10% Bi 0.1 to 2% Sn remainder plus incidental impurities.

3. The industrial bearing component of claim 1 wherein the friction-resistant alloy comprises, by approximate weight %: Sb 3 to 6% Cu 3 to 6% Bi 0.1 to 2% Sn remainder plus incidental impurities.

4. The industrial bearing component of claim 1 wherein the friction-resistant alloy comprises, by approximate weight %: Sb 7 to 9% Cu 7 to 9% Bi 0.25 to 2% Sn remainder plus incidental impurities.

5. The industrial bearing component of claim 1 wherein the friction-resistant alloy comprises, by approximate weight %: Sb 6 to 9% Cu 2 to 5% Bi 0.25 to 2% Sn remainder plus incidental impurities.

6. The industrial bearing component of claim 1 wherein the friction-resistant alloy consists of, by approximate weight %: Sb 3 to 15% Cu 0.5 to 10% Bi 0.1 to 2% Sn remainder plus incidental impurities.

7. The industrial bearing component of claim 1 wherein the friction-resistant alloy consists of, by approximate weight %: Sb 3 to 6% Cu 3 to 6% Bi 0.1 to 2% Sn remainder plus incidental impurities.

8. The industrial bearing component of claim 1 wherein the friction-resistant alloy consists of, by approximate weight %: Sb 7 to 9% Cu 7 to 9% Bi 0.25 to 2% Sn remainder plus incidental impurities.

9. The industrial bearing component of claim 1 wherein the friction-resistant alloy consists of, by approximate weight %: Sb 6 to 9% Cu 2 to 5% Bi 0.25 to 2% Sn remainder plus incidental impurities.

10. The industrial bearing component of claim 1 wherein the friction-resistant alloy is Pb-free, Cd-free, As-free and comprises, by approximate weight %: Sb 3 to 15% Cu 0.5 to 10% Bi 0.1 to 2% Sn remainder plus incidental impurities.

11. The industrial bearing component of claim 1 wherein the friction-resistant alloy is Ni-free, Ag-free, Zn-free and comprises, by approximate weight %: Sb 3 to 15% Cu 0.5 to 10% Bi 0.1 to 2% Sn remainder plus incidental impurities.

12. The industrial bearing component of claim 1 wherein the friction-resistant alloy is Pb-free, Cd-free, As-free, and comprises, by approximate weight %: Sb 3 to 6% Cu 3 to 6% Bi 0.1 to 2% Sn remainder plus incidental impurities.

13. The industrial bearing component of claim 1 wherein the friction-resistant alloy is Ni-free, Ag-free, Zn-free, and comprises, by approximate weight %: Sb 3 to 6% Cu 3 to 6% Bi 0.1 to 2% Sn remainder plus incidental impurities.

14. The industrial bearing component of claim 1 wherein the friction-resistant alloy is Pb-free, Cd-free, As-free, and comprises, by approximate weight %: Sb 7 to 9% Cu 7 to 9% Bi 0.25 to 2% Sn remainder plus incidental impurities.

15. The industrial bearing component of claim 1 wherein the friction-resistant alloy is Ni-free, Ag-free, Zn-free, and comprises, by approximate weight %: Sb 7 to 9% Cu 7 to 9% Bi 0.25 to 2% Sn remainder plus incidental impurities.

16. The industrial bearing component of claim 1 wherein the friction-resistant alloy is Pb-free, Cd-free, As-free, and comprises, by approximate weight %: Sb 6 to 9% Cu 2 to 5% Bi 0.25 to 2% Sn remainder plus incidental impurities.

17. The industrial bearing component of claim 1 wherein the friction-resistant alloy is Ni-free, Ag-free, Zn-free, and comprises, by approximate weight %: Sb 6 to 9% Cu 2 to 5% Bi 0.25 to 2% Sn remainder plus incidental impurities.

18. The industrial bearing component of claim 1 wherein the friction-resistant alloy comprises, by approximate weight %: Sb 3 to 15% Cu 0.5 to 10% Bi 0.1 to 2% Ni 0.1 to 0.5% Sn remainder plus incidental impurities.

19. The industrial bearing component of claim 1 wherein the friction-resistant alloy comprises, by approximate weight %: Sb 3 to 6% Cu 3 to 6% Bi 0.1 to 2% Ni 0.1 to 0.5% Sn remainder plus incidental impurities.

20. The industrial bearing component of claim 1 wherein the friction-resistant alloy comprises, by approximate weight %: Sb 7 to 9% Cu 7 to 9% Bi 0.25 to 2% Ni 0.1 to 0.5% Sn remainder plus incidental impurities.

21. The industrial bearing component of claim 1 wherein the friction-resistant alloy comprises, by approximate weight %: Sb 6 to 9% Cu 2 to 5% Bi 0.25 to 2% Ni 0.1 to 0.5% Sn remainder plus incidental impurities.

22. The industrial bearing component of claim 1 wherein the friction-resistant alloy consists of, by approximate weight %: Sb 3 to 15% Cu 0.5 to 10% Bi 0.1 to 2% Ni 0.1 to 0.5% Sn remainder plus incidental impurities.

23. The industrial bearing component of claim 1 wherein the friction-resistant alloy consists of, by approximate weight %: Sb 3 to 6% Cu 3 to 6% Bi 0.1 to 2% Ni 0.1 to 0.5% Sn remainder plus incidental impurities.

24. The industrial bearing component of claim 1 wherein the friction-resistant alloy consists of, by approximate weight %: Sb 7 to 9% Cu 7 to 9% Bi 0.25 to 2% Ni 0.1 to 0.5% Sn remainder plus incidental impurities.

25. The industrial bearing component of claim 1 wherein the friction-resistant alloy consists of, by approximate weight %: Sb 6 to 9% Cu 2 to 5% Bi 0.25 to 2% Ni 0.1 to 0.5% Sn remainder plus incidental impurities.

26. The industrial bearing component of claim 1 wherein the friction-resistant alloy is Pb-free, Cd-free, As-free and comprises, by approximate weight %: Sb 3 to 15% Cu 0.5 to 10% Bi 0.1 to 2% Ni 0.1 to 0.5% Sn remainder plus incidental impurities.

27. The industrial bearing component of claim 1 wherein the friction-resistant alloy is Ag-free, Zn-free and comprises, by approximate weight %: Sb 3 to 15% Cu 0.5 to 10% Bi 0.1 to 2% Ni 0.1 to 0.5% Sn remainder plus incidental impurities.

28. The industrial bearing component of claim 1 wherein the friction-resistant alloy is Pb-free, Cd-free, As-free, and comprises, by approximate weight %: Sb 3 to 6% Cu 3 to 6% Bi 0.1 to 2% Ni 0.1 to 0.5% Sn remainder plus incidental impurities.

29. The industrial bearing component of claim 1 wherein the friction-resistant alloy is Ag-free, Zn-free, and comprises, by approximate weight %: Sb 3 to 6% Cu 3 to 6% Bi 0.1 to 2% Ni 0.1 to 0.5% Sn remainder plus incidental impurities.

30. The industrial bearing component of claim 1 wherein the friction-resistant alloy is Pb-free, Cd-free, As-free, and comprises, by approximate weight %: Sb 7 to 9% Cu 7 to 9% Bi 0.25 to 2% Ni 0.1 to 0.5% Sn remainder plus incidental impurities.

31. The industrial bearing component of claim 1 wherein the friction-resistant alloy is Ag-free, Zn-free, and comprises, by approximate weight %: Sb 7 to 9% Cu 7 to 9% Bi 0.25 to 2% Ni 0.1 to 0.5% Sn remainder plus incidental impurities.

32. The industrial bearing component of claim 1 wherein the friction-resistant alloy is Pb-free, Cd-free, As-free, and comprises, by approximate weight %: Sb 6 to 9% Cu 2 to 5% Bi 0.25 to 2% Ni 0.1 to 0.5% Sn remainder plus incidental impurities.

33. The industrial bearing component of claim 1 wherein the friction-resistant alloy is Ag-free, Zn-free, and comprises, by approximate weight %: Sb 6 to 9% Cu 2 to 5% Bi 0.25 to 2% Ni 0.1 to 0.5% Sn remainder plus incidental impurities.

34. A friction-resistant alloy for use as a bearing surface, the alloy being a tin matrix containing copper, antimony, and between about 0.10% and about 2% by weight bismuth.

35. The alloy of claim 34 comprising, by approximate weight %: Sb 3 to 15% Cu 0.5 to 10% Bi 0.1 to 2% Sn remainder plus incidental impurities.

36. The alloy of claim 34 comprising, by approximate weight %: Sb 3 to 6% Cu 3 to 6% Bi 0.1 to 2% Sn remainder plus incidental impurities.

37. The alloy of claim 34 comprising, by approximate weight %: Sb 7 to 9% Cu 7 to 9% Bi 0.25 to 2% Sn remainder plus incidental impurities.

38. The alloy of claim 34 comprising, by approximate weight %: Sb 6 to 9% Cu 2 to 5% Bi 0.25 to 2% Sn remainder plus incidental impurities.

39. The alloy of claim 34 consisting of, by approximate weight %: Sb 3 to 15% Cu 0.5 to 10% Bi 0.1 to 2% Sn remainder plus incidental impurities.

40. The alloy of claim 34 consisting of, by approximate weight %: Sb 3 to 6% Cu 3 to 6% Bi 0.1 to 2% Sn remainder plus incidental impurities.

41. The alloy of claim 34 consisting of, by approximate weight %: Sb 7 to 9% Cu 7 to 9% Bi 0.25 to 2% Sn remainder plus incidental impurities.

42. The alloy of claim 34 consisting of, by approximate weight %: Sb 6 to 9% Cu 2 to 5% Bi 0.25 to 2% Sn remainder plus incidental impurities.

43. The alloy of claim 34 wherein the alloy is Pb-free, Cd-free, As-free, and comprises, by approximate weight %: Sb 3 to 15% Cu 0.5 to 10% Bi 0.1 to 2% Sn remainder plus incidental impurities.

44. The alloy of claim 34 wherein the alloy is Nifree, Ag-free, Zn-free, and comprises, by approximate weight %: Sb 3 to 15% Cu 0.5 to 10% Bi 0.1 to 2% Sn remainder plus incidental impurities.

45. The alloy of claim 34 wherein the alloy is Pb-free, Cd-free, As-free, and comprises, by approximate weight %: Sb 3 to 6% Cu 3 to 6% Bi 0.1 to 2% Sn remainder plus incidental impurities.

46. The alloy of claim 34 wherein the alloy is Ni-free, As-free, Zn-free, and comprises, by approximate weight % Sb 3 to 6% Cu 3 to 6% Bi 0.1 to 2% Sn remainder plus incidental impurities.

47. The alloy of claim 34 wherein the alloy is Pb-free, Cd-free, As-free, and comprises, by approximate weight %: Sb 7 to 9% Cu 7 to 9% Bi 0.25 to 2% Sn remainder plus incidental impurities.

48. The alloy of claim 34 wherein the alloy is Ni-free, Ag-free, Zn-free, and comprises, by approximate weight %: Sb 7 to 9% Cu 7 to 9% Bi 0.25 to 2% Sn remainder plus incidental impurities.

49. The alloy of claim 34 wherein alloy is Pb-free, Cd-free, As-free, and comprises, by approximate weight %: Sb 6 to 9% Cu 2 to 5% Bi 0.25 to 2% Sn remainder plus incidental impurities.

50. The alloy of claim 34 wherein the alloy is Ni-free, Ag-free, Zn-free, and comprises, by approximate weight %: Sb 6 to 9% Cu 2 to 5% Bi 0.25 to 2% Sn remainder plus incidental impurities.

51. The alloy of claim 34 wherein the alloy comprises, approximate weight %: Sb 3 to 15% Cu 0.5 to 10% Bi 0.1 to 2% Ni 0.1 to 0.5% Sn remainder plus incidental impurities.

52. The alloy of claim 34 wherein the alloy comprises, by approximate weight %: Sb 3 to 6% Cu 3 to 6% Bi 0.1 to 2% Ni 0.1 to 0.5% Sn remainder plus incidental impurities.

53. The alloy of claim 34 wherein the alloy comprises, by approximate weight %: Sb 7 to 9% Cu 7 to 9% Bi 0.25 to 2% Ni 0.1 to 0.5% Sn remainder plus incidental impurities.

54. The alloy of claim 34 wherein the alloy comprises, by approximate weight %: Sb 6 to 9% Cu 2 to 5% Bi 0.25 to 2% Ni 0.1 to 0.5% Sn remainder plus incidental impurities.

55. The alloy of claim 34 wherein the alloy consists of, by approximate weight %: Sb 3 to 15% Cu 0.5 to 10% Bi 0.1 to 2% Ni 0.1 to 0.5% Sn remainder plus incidental impurities.

56. The alloy of claim 34 wherein the alloy consists of, by approximate weight %: Sb 3 to 6% Cu 3 to 6% Bi 0.1 to 2% Ni 0.1 to 0.5% Sn remainder plus incidental impurities.

57. The alloy of claim 34 wherein the alloy consists of, by approximate weight %: Sb 7 to 9% Cu 7 to 9% Bi 0.25 to 2% Ni 0.1 to 0.5% Sn remainder plus incidental impurities.

58. The alloy of claim 34 wherein the alloy consists of, by approximate weight %: Sb 6 to 9% Cu 2 to 5% Bi 0.25 to 2% Ni 0.1 to 0.5% Sn remainder plus incidental impurities.

59. The alloy of claim 34 wherein the alloy is Pb-free, Cd-free, As-free and comprises, by approximate weight Sb 3 to 15% Cu 0.5 to 10% Bi 0.1 to 2% Ni 0.1 to 0.5% Sn remainder plus incidental impurities.

60. The alloy of claim 34 wherein the alloy is Ag-free, Zn-free and comprises, by approximate weight %: Sb 3 to 15% Cu 0.5 to 10% Bi 0.1 to 2% Ni 0.1 to 0.5% Sn remainder plus incidental impurities.

61. The alloy of claim 34 wherein the alloy is Pb-free, Cd-free, As-free, and comprises, by approximate weight %: Sb 3 to 6% Cu 3 to 6% Bi 0.1 to 2% Ni 0.1 to 0.5% Sn remainder plus incidental impurities.

62. The alloy of claim 34 wherein the alloy is Ag-free, Zn-free, and comprises, by approximate weight %: Sb 3 to 6% Cu 3 to 6% Bi 0.1 to 2% Ni 0.1 to 0.5% Sn remainder plus incidental impurities.

63. The alloy of claim 34 wherein the alloy is Pb-free, Cd-free, As-free, and comprises, by approximate weight %: Sb 7 to 9% Cu 7 to 9% Bi 0.25 to 2% Ni 0.1 to 0.5% Sn remainder plus incidental impurities.

64. The alloy of claim 34 wherein the alloy is Ag-free, Zn-free, and comprises, by approximate weight %: Sb 7 to 9% Cu 7 to 9% Bi 0.25 to 2% Ni 0.1 to 0.5% Sn remainder plus incidental impurities.

65. The alloy of claim 34 wherein the alloy is Pb-free, Cd-free, As-free, and comprises, by approximate weight %: Sb 6 to 9% Cu 2 to 5% Bi 0.25 to 2%. Ni 0.1 to 0.5% Sn remainder plus incidental impurities.

66. The alloy of claim 34 wherein the alloy is Ag-free, Zn-free, and comprises, by approximate weight %: Sb 6 to 9% Cu 2 to 5% Bi 0.25 to 2% Ni 0.1 to 0.5% Sn remainder plus incidental impurities.

67. The alloy of claim 34 wherein the alloy has a time to elevated temperature creep rupture of at least about 100 hours when tested at 160° F. and in accordance with procedures of ASTM E139-96.

68. A friction-resistant alloy for use as a bearing surface, the alloy being a tin matrix containing about 3.7 wt % Cu, 7.3 wt % Sb, 1.5 wt % Bi, balance Sn, plus incidental impurities.