Ti3SiC2、不锈钢和NiCr合金在人工海水中的摩擦学性能

在SRV-1型摩擦磨损试验机上考察了Ti3SiC2、NiCr合金和不锈钢在干摩擦、蒸馏水和人工海水中的摩擦磨损性能,并用扫描电镜(SEM-EDS)及光电子能谱(XPS)对磨痕形貌及成分进行分析.结果表明:Ti3SiC2/Al2O3摩擦副的摩擦系数对摩擦条件变化不敏感,在液体介质中磨损稍有降低.3种摩擦条件下存在机械磨损和摩擦氧化磨损竞争,但机械磨损始终为主要磨损机制,因此摩擦和磨损较大.不锈钢/Al2O3和NiCr合金/Al2O3两摩擦副对摩擦条件变化较敏感,摩擦系数和磨损率在于摩擦、蒸馏水和海水中依次降低,其中NiCr合金降低幅度最大.干摩擦条件下两者以机械磨损为主要磨损机制,表现为黏着磨损和材料转移;蒸馏水中机械磨损和摩擦氧化磨损并存;海水中以腐蚀磨损为主导,腐蚀产物FeCl2、CrCl3或CrO22-或CrO2-等具有减摩抗磨作用.

Tribological Properties of Ti3SiC2, Stainless Steel and NiCr Alloy in Artificial Seawater

The tribological properties of Ti₃SiC₂, stainless steel and NiCr alloy under dry sliding, in distilled and sea water were investigated on an SRV-1 tribometer. The worn surfaces were analyzed by using scanning electron microscopy and X-ray photoelectron spectrometer. The results show that the friction coefficient of Ti₃SiC₂/Al₂O₃ tribo-pair was insensitive to sliding condition. The wear rate of Ti₃SiC₂ in liquids (distilled water and sea water) was one order of magnitude lower than that under dry sliding. In the competition between the two wear mechanisms of mechanical wear and tribo-oxidation wear, mechanical wear was the dominant mechanism, which was independent on the sliding condition. So the friction coefficient and wear were high for Ti₃SiC₂/Al₂O₃ tribo-pair under the three sliding conditions. Tribological properties of stainless steel/Al₂O₃ and NiCr alloy/Al₂O₃ were sensitive to sliding condition. The friction coefficient and wear rate of stainless steel and NiCr alloy successively decreased in the order of dry sliding, distilled water, and sea water. The degree of decrease was the largest for NiCr alloy/Al₂O₃ tribo-pair. Under dry sliding mechanical wear was the dominant wear mechanism for both the tribo-pairs. In distilled water both mechanical wear and tribo-oxidation wear worked. In the sea water corrosion wear was the main wear mechanism. The tribo-corrosive products (FeCl₂, CrCl₃ or CrO₂^2- and CrO₄^2-) were lubricants to decrease the friction and wear.