机械液压零部件的表面涂层与耐磨性能研究

Study on surface coating and wear resistance of mechanical and hydraulic components

采用等离子喷涂和等离子喷焊的方法,在机械液压杆用Q235钢表面制备了Ni基WC复合涂层,对比分析了两种涂层的显微形貌、硬度和耐磨性能等。结果表明,等离子喷涂和等离子喷焊涂层表面WC颗粒平均尺寸分别为35μm和20μm,等离子喷焊涂层表面尺寸较大的块状WC颗粒数量减少且同时存在碎片状二次重熔相。等离子喷涂和等离子喷焊涂层都主要含有WC、W2C、Cr7C3、Cr3C2和Ni-Cr-Fe相,但等离子喷焊涂层中除(Cr,Ni,Fe)3C2和(Cr,Ni,Fe)7C3相外,还含有较多的二次碳化物。等离子喷涂态和喷焊态涂层的洛氏硬度分别为62HRC和59HRC;相同磨损时间下,喷涂态涂层的磨损失重小于喷焊态涂层,等离子喷涂态Ni基WC复合涂层具有更好的耐磨性能。

Ni-based WC composite coatings were prepared on the surface of Q235 steel for mechanical hydraulic rods by plasma spraying and plasma spraying.The morphology,phase composition and wear resistance of the two coatings were compared and analyzed.The results show that the average size of WC particles on plasma spraying and plasma spraying coatings are 35μm and 20μm,respectively.The number of large WC particles on plasma spraying coatings decreases and there are fragmental secondary remelting phases at the same time.The plasma spraying and plasma spraying coatings mainly contain WC,W2 C,Cr7 C3,Cr3 C2 and Ni-Cr-Fe phases,but the plasma spraying coatings contain more secondary carbides besides(Cr,Ni,Fe)3 C2 and(Cr,Ni,Fe)7 C3 phases.The Rockwell hardness of plasma sprayed and sprayed coatings are 62 HRC and 59 HRC,respectively.At the same wear time,the wear loss of sprayed coatings is less important than that of sprayed coatings,the plasma sprayed Nibased WC composite coatings have better wear resistance.