氮气、空气条件下炭/炭复合材料的摩擦磨损性能

在MM-1000型摩擦试验机上,对炭/炭复合材料分别在氮气和空气中模拟正常着陆能量条件下的摩擦磨损行为进行测试。结果表明:在氮气中,炭/炭复合材料的摩擦因数较高,达到0.32～0.4,磨损率较低,质量磨损率为18 mg/次,线性磨损率为1.4μm/次;在空气中,材料的摩擦因数较低,为0.2～0.3,但磨损率较高,质量磨损率为48 mg/次,线性磨损率为3.8μm/次。磨损表面及磨屑的SEM形貌表明:在空气中,材料摩擦表面易形成炭纤维、基体炭相互脱离的磨屑,其主要磨损机制为氧化磨损;在氮气中,则有纤维与基体炭连接良好、大尺寸的磨屑出现,主要磨损机制为磨粒磨损和粘着磨损。

Friction and wear properties of C/C composite materials in nitrogen and air atmospheres

The friction and wear behaviors of C/C composites in nitrogen and air environments under simulating normal landing energy condition were investigated on the MM-1000 friction tester.The results show that C/C composites exhibit the higher friction coefficient(0.32～0.4) but the smaller wear rate in N2,mass wear rate and linear wear rate are 18 mg/times and 1.4 μm/times,respectively;however,C/C composites shows the lower friction coefficient which is 0.2～0.3 but the larger wear rate in air,mass wear rate and linear wear rate are 48 mg/times and 3.8 μm/times,respectively.The SEM morphologies of worn surface and wear debris show that in air,wear debris which carbon fiber separates from carbon matrix appear on the worn surface,wear mechanism is mainly oxidation wear.However,in N2,large-size debris which carbon fiber is well-connected with carbon matrix appear,wear mechanisms are mainly abrasive wear and adhesive wear.