化学刻蚀高硅铝合金缸套的摩擦磨损性能

Wear Behaviour of the Chemical Etching High-silicon Aluminium Alloy Cylinder Liner

采用对置往复式摩擦磨损试验机,选用铬基陶瓷复合镀活塞环(CKS环)为配副试样,研究机械珩磨+化学刻蚀法加工高硅铝合金缸套的摩擦磨损性能。通过测量摩擦因数、磨损量,用扫描电子显微镜(SEM)和激光共聚焦显微镜(LSM)观察分析摩擦副磨损前后表面形貌。结果表明:在20℃下,将机械珩磨的高硅铝合金缸套试样浸入浓度为5%的NaOH溶液中腐蚀2min,可制备出硅颗粒凸出高度约为1μm的工作表面;相对于单纯采用机械珩磨加工方法制备的高硅铝合金缸套,机械珩磨+化学刻蚀加工的高硅铝合金缸套摩擦副的摩擦因数可从0.141 41降至0.129 56,降幅约为8.38%,两者的磨损量相近。采用机械珩磨加工方法的高硅铝合金缸套磨损试验后表面有磨粒磨损带来的轻微划痕,而化学刻蚀后的缸套磨损表面没有发现划痕现象,与其对磨的活塞环的磨损状况也较轻微。

Using a contraposition reciprocating test rig,this paper investigates the wear behavior of the high-silicon aluminium alloy cylinder liner machined by mechanical honing and chemical etching,which is worn with chromkeramik-schicht（CKS）piston ring.The friction coefficient and weight loss of the pair are measured.The surface morphology is obtained through scanning electron microscope（SEM）and laser scanning microscope（LSM）.The results show that the protrusion height of silicon particles is about 1μm by dipping the cylinder bore sample into 5%NaOH liquor for two minutes at 20 ℃.The friction coefficient of the high-silicon aluminium alloy cylinder liner through chemical etching after mechanical honing can be reduced 8.38%than mechanical honing,from 0.141 41to0.129 56.The weight loss is similar.Slight scratches for abrasive wear are found on the cylinder bore wear surface through mechanical honing;however,no scratches are found on the chemical etching cylinder bore wear surface,and the piston ring against it is worn more slightly than mechanical honing cylinder bore.