微型轴承性能的测试与分析

MEASUREMENT AND ANALYSIS OF THE PERFORMANCE OF MINITYPE BEARING

利用一种新的测试方法,对轴颈尺寸在百微米级、摩擦力为mN级的微型轴承的摩擦性能进行了测试与分析。着重研究了三种不同材料（钢,铜,硬质合金）轴瓦与高速钢轴颈的摩擦性能。研究发现,材料相对硬度以及表面质量对微型轴承的摩擦因数有明显影响;轴颈转速（在100～1200r/min）对微型轴承的摩擦因数影响则较小。在小载荷（5～70 mN）作用时,载荷变化对摩擦因数的影响较小。在3种摩擦副中,铜瓦一钢轴摩擦副的性能最好。

Friction properties of micro journal bearings are investigated with special developed test-rig. The bearings with journal diameter of several hundreds of micro meter are sub-jected to a small contacting load of several milli-Newton. Three kinds of bearing materials including mild steel, copper and cemented carbide are tested against the journal made of high-carbon steel under different contacting load and rotation speed. It is found that the material hardness and the surface roughness of the bearing have obvious influence on the friction coefficient. The change of rotation speed (100-1 200 r/min) has small influence on friction coefficient. The change of contacting load (5-70 mN) only result in slight decrease of friction coefficient. Among the three pairs of micro bearings, the copper bearing against high-carbon steel journal exhibits best friction performance.