Page 27 - The Tribology Handbook

A4 Plain bearing materials

Relative load-carrying capacities of bearing materials, and recommended journal hardness

Recommended
Maximum dynamic loading journal hardness
Material
MNIm’ Ibf/in2 Hv min at
20°C
Tin and lead-base white metal linings -0.5 mm (0.020 in) thick 10.3-13.7 1500-2000 Soft journal
(-1 40) satisfactory
As above -0.1 mm (0.004 in) thick > 17.2 > 2500 As above
~ ~~~~ ~~ ~~
70/30 copper-lead on steel 24-27.5 3500-4000 -250
70/30 copper-lead on steel, overlay plated 27.5-31 40004500 -230
Lead bronze, 20-25% lead, 3-5% tin, on steel 35-42 5000-6000 -500
~~~~~ ~
As above, overlay plated 42-52 6000-7500 -230
Low lead (-loyo) lead bronzes, steel-backed > 48 > 7000 -500

Aluminium-6~o tin, ‘solid’ or steel-backed -42 -6000 -500
kF, above, overlay plated 45-52 6500-7500 -280
Aluminium-20% tir. (reticular structure) on steel -42 -6000 -230
Aluminium-tin-silicon on steel -52 -7500 -250

Phosphor-bronze, chill or continuously cast -62 -9000 -500
Note: the above figures must be interpreted with caution, as they apply only to specific testing conditions. They should not be used for
design purposes without first consulting the appropriate bearing supplier.
Fatigue strength and relative compatibility of some bearing all0 ys (courtesy: Glacier Metal
Company Limited)
Fatigue rating(’) Seizure hd‘’’
Material
MN/m2 Ibf/in2 MN/m’ lbf/inz
Tin-base white metal 35 5000 14 2000 not seized

Lead-base white metal 35 5000 14 2000 not seized
70130 copper-lead, unplated 95 13 500 11-14 1600-2000
70130 copper-lead, overlay plated 70 1 O OOO overlay -t3) -(3)
119 17 000 copper- - -( 3 )
(31
lead
Lead bronze (22% lead, 4% tin), unplated - - 5.5-1 1 800- 1600
___ ~
Lead bronze (22% lead, 4% tin), overlay plated 70 10 000 overlay -(3) -( 3 )
125 18 000 lead
bronze
Lead bronze (10% lead, 10% tin), unplated - - 3-8.5 400-1200
6% tin-aluminium, unplated 105 15 000 5.5-14 80Cb2000
6% tin-aluminium, overlay plated 76 11 000 overlay -(’I -(31
114 16 500 tin- -(31 -(31
aluminium
Aluminium-tin-silicon 118 13000 10-14 1500-2000
Aluminium-20% tin 90 13000 14 2000 usually
-
Notes: (1) Fatigue ratings determined on single-cylinder test rig. Not to be used for engine design purposes.
(2) Seizure load determined by stop-start tests on bushes. Maximum load on rig 14 MN/m2 (2000 lbf/in2).
(3) Overlay does not seize, but wears away. Seizure then occurs between interlayer and journal at load depending upon thickness
of overlay, i.e. rate of wear. The overlay thickness on aluminium-tin is usually less than that on copper4ead and lead bronze,
hence the slightly higher fatigue rating.
A4.4