不同温度下铜基粉末冶金摩擦材料往复滑动磨损规律

FATIGUE WEAR OF RECIPROCATING SLIDING FOR COPPER-BASE POWDER METALLURGY(Cu-PM) FRICTION MATERIAL UNDER VARIED TEMPERATURE

研究不同温度下高速列车用铜基粉末冶金摩擦材料磨损特征。在PlintTE77高温疲劳试验机上对该材料进行磨损性能测试 ,工况分别为室温、10 0℃、2 0 0℃、3 0 0℃、3 5 0℃、5 0 0℃ ,法向载荷为 2 0 0N、45 0N等 12种工况 ,振动频率为 4Hz ,滑动幅值为± 5mm。并对摩擦后的磨痕进行Scanelectro mirror (SEM)分析。发现①在 2 0 0N、3 0 0℃时出现碾压的多源弧形裂纹 ,这和冲击时的沿树枝晶裂纹截然不同。②在 45 0N、3 0 0℃时 ,磨痕表面出现球状的石墨颗粒层 ,这起到了极好的润滑作用 ,使得 3 0 0℃时磨损较低。③在 45 0N、3 5 0℃时 ,有沿磨痕方向的长条裂纹出现。④在不同载荷 5 0 0℃时 ,发生粘附现象 ,即摩擦材料粘附到对偶材料上。

High temperature friction wear properties of Cu-PM(power metallurgy) for high-speed train are investigated and the high temperature wear parameters are measured by Plint TE77 high temperature fatigue equipment. Cases are room temperature, 100℃, 200℃, 300℃, 350℃, 500℃; forces are 200?N, 450?N; vibration frequency is 4?Hz; sliding displacement is ±5?mm; and analyzed the wear scar after 15?000 cycles by SEM. Found(1)There are the multi-sources arc crack at 200?N, 300℃, it is different to impact crack with tree shape. (2)There are graphite coating on the surface, it is a good lubrication coating, it made a less wear at 450?N,300℃. (3)There are a strip crack along wear scar after 15?000 at 450?N, 300℃. (4)Take place negative wear, that is, the friction material adhere to the match material at 500℃, various pressures, but the coefficient of friction is the biggest. Fitted rough the wear law by the least square method.