扫描速度对缸套等离子束淬火层组织性能的影响

Effect of Scanning Speed on Microstructure Properties of Equal Ion Beam Quenched Layer Such As Cylinder Liner

针对气缸套内表面磨损失效呈现漏斗状现象,采用等离子束淬火专用设备,通过控制扫描速度随等离子束淬火工作行程逐渐降低,在气缸套内表面从下至上制备了强化层,并在试车台上考察了淬火层的摩擦学性能。采用OM、SEM、CLSM和硬度计等,对缸套内表面等离子束淬火前后的组织性能和磨损形貌进行了测试观察分析。结果表明:不同扫描速度下硬化带组织均由隐针马氏体+残余奥氏体组成。随着扫描速度的逐渐降低,残余奥氏体含量逐渐减小,硬化带的硬度、深度、宽度和高度逐渐增加,气缸套内表面自下而上磨损量几乎相同,最大磨损量相对原气缸套内径减少73.53%。这归因于扫描速度的逐渐降低对气缸套内表面的强化作用从下至上逐渐增强。

In view of the phenomenon that the wear failure of the inner surface of the cylinder liner appears like a funnel,a special equipment for equal ion beam quenching was used to prepare a strengthened layer on the inner surface of the cylinder liner from bottom to top by controlling the scanning speed and decreasing gradually with the working stroke of equal ion beam quenching.The tribological properties of the hardened layer were investigated on the test bench.The microstructure and wear morphology of the inner surface of cylinder liner before and after ion beam quenching were measured and analyzed by OM,SEM,CLSM and hardness tester.The results showed that the hardened band was composed of hidden needle martensite+residual austenite at different scanning speeds.With the decreasing of the scanning speed,the residual austenite content gradually decreased,the hardness,depth,width and height of the hardened belt gradually increased,and the bottom-up wear of the inner surface of the cylinder liner was almost the same,and the maximum wear was reduced by 73.53% compared with the inner diameter of the original cylinder liner.This is due to the gradual reduction of the scanning speed and the strengthening of the inner surface of the cylinder liner from the bottom up.