Machinery's Handbook, 31st Edition
2436
Plain Bearing Materials Table 1. Bearing and Bushing Alloys—Composition, Forms, Characteristics, and Applications SAE General Information
SAE No. and Alloy Grouping
Nominal Composition, Percent
Form of Use (1), Characteristics (2), and Applications (3)
(1) Cast on steel, bronze, or brass backs, or directly in the bearing housing. (2) Soft, corrosion-resistant with moderate fatigue resistance. (3) Main and connecting-rod bearings; motor bushings. Operates with either hard or soft journal. (1) SAE 13 and 14 are cast on steel, bronze, or brass, or in the bearing housing; SAE 15 is cast on steel; and SAE 16 is cast into and on a porous sintered matrix, usually copper-nickel bonded to steel. (2) Soft, moderately fatigue-resistant, corrosion-resistant. (3) Main and connecting-rod bearings. Operates with hard or soft journal with good finish. (1) Electrodeposited as a thin layer on copper-lead or silver bearings faces. (2) Soft, corrosion-resistant. Bearings so coated run satisfactorily against soft shafts throughout the life of the coating. (3) Heavy-duty, high-speed main and connecting-rod bearings. (1) Cast or sintered on steel back with the exception of SAE 481, which is cast on steel back only. (2) Moderately hard. Somewhat subject to oil corrosion. Some oils minimize this; protection with overlay may be desirable. Fatigue resistance good to fairly good. Listed in order of decreasing hardness and fatigue resistance. (3) Main and connecting-rod bearings. The higher lead alloys can be used unplated against a soft shaft, although an overlay is helpful. The lower lead alloys may be used against a hard shaft, or with an overlay against a soft one. (1) Steel-backed and lined with a structure combining sintered copper alloy matrix with corrosion-resistant lead alloy. (2) Moderately hard. Corrosion resistance improved over copper-leads of equal lead content without tin. Fatigue resistance fairly good. Listed in order of decreasing hardness and fatigue resistance. (3) Main and connecting-rod bearings. Generally used without overlay. SAE 484 and 485 may be used with hard or soft shaft, and a hardened or cast shaft is recommended for SAE 482. (1) SAE 770 cast in permanent molds; work-hardened to improve physical properties. SAE 780 and 782 usually bonded to steel back but is procurable in strip form without steel backing. SAE 781 usually bonded to steel back but can be produced as castings or wrought strip without steel back. (2) Hard, extremely fatigue-resistant, resistant to oil corrosion. (3) Main and connecting-rod bearings. Generally used with suitable overlay. SAE 781 and 782 also used for bushings and thrust bearings with or without overlay.
11 Sn, 87.5; Sb, 6.75; Cu, 5.75 12 Sn, 89; Sb, 7.5; Cu, 3.5 13 Pb, 84; Sb, 10; Sn, 6 14 Pb, 75; Sb, 15; Sn, 10 15 Pb, 83; Sb, 15; Sn, 14; As, 1 16 Pb, 92; Sb, 3.5; Sn, 4.5
Sn-Base Alloys
Pb-Base Alloys
19 Pb, 90; Sn, 10 190 Pb, 93; Sn, 7 49 Cu, 76; Pb, 24 48 Cu, 70; Pb, 30 480 Cu, 65; Pb, 35
Pb-Sn Overlays
Cu-Pb Alloys
481 Cu, 60; Pb, 40
482 Cu, 67; Pb, 28; Sn, 5 484 Cu, 55; Pb, 42; Sn, 3
Cu-Pb-Sn Alloys
485 Cu, 46; Pb, 51; Sn, 3
770 Al, 91.75; Sn, 6.25; Cu, 1; Ni, 1
780 Al, 91; Sn, 6; Si, 1.5; Cu, 1; Ni, 0.5 781 Al, 95; Si, 4; Cd, 1 782 Al, 95; Cu, 1; Ni, 1; Cd, 3
Al-Base Alloys
795 Cu, 90; Zn, 9.5; Sn, 0.5 (1) Wrought solid bronze, (2) Hard, strong, good fatigue resistance, (3) Intermediate-load oscillating motion such as tie-rods and brake shafts. 791 Cu, 88; Zn, 4; Sn, 4; Pb, 4 (1) SAE 791, wrought solid bronze; SAE 793, cast on steel back; SAE
Other Cu-Base Alloys
798, sintered on steel back. (2) General-purpose bearing material, good shock and load capacity. Resistant to high temperatures. Hard shaft desirable. Less score-resistant than higher lead alloys. (3) Medium to high loads. Transmission bushings and thrust washers. SAE 791 also used for piston pin and 793 and 798 for chassis bushings.
793 Cu, 84; Pb, 8; Sn, 4; Zn, 4 798 Cu, 84; Pb, 8; Sn, 4; Zn, 4
792 Cu, 80; Sn, 10; Pb, 10 (1) SAE 792, cast on steel back, SAE 797, sintered on steel back. (2) Has maximum shock and load-carrying capacity of conventional cast bearing alloys; hard, both fatigue- and corrosion-resistant. Hard shaft desirable. (3) Heavy loads with oscillating or rotating motion. Used for piston pins, steering knuckles, differential axles, thrust washers, and wear plates. 797 Cu, 80; Sn, 10; Pb, 10 794 Cu, 73.5; Pb, 23; Sn, 3.5 (1) SAE 794, cast on steel back; SAE 799, sintered on steel back.
Other Cu-Base Alloys
(2) Higher lead content gives improved surface action for higher speeds but results in somewhat less corrosion resistance. (3) Intermediate load application for both oscillating and rotating shafts, that is, rocker-arm bushings, transmissions, and farm implements.
799 Cu, 73.5; Pb, 23; Sn, 3.5
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