槽电压对纯铁表面液相等离子体电解硼碳氮三元共渗层摩擦磨损性能的影响

利用液相等离子体电解渗技术分别在340,360V和380V槽电压下对纯铁进行硼碳氮三元共渗(PEB/C/N)表面处理。分析纯铁表面PEB/C/N共渗层的形貌、成分、相组成和显微硬度分布。采用球-盘摩擦磨损仪评估槽电压对渗层摩擦磨损性能的影响,并分析渗层与ZrO_2球对磨时磨损机理。纯铁表面的PEB/C/N三元共渗层厚度随着放电电压升高而增大,最高硬度也相应增加。380V处理1h后硼碳氮三元共渗层中渗硼层和过渡层厚度分别达到26μm和34μm,渗层最高硬度可以达到2318HV。硼碳氮三元共渗层的磨损率仅为纯铁基体的1/10。硼碳氮共渗处理大幅度降低纯铁的摩擦因数和磨损率,但不同槽电压下制备的PEB/C/N共渗层的摩擦因数和磨损率变化较小。

Influence of Bath Voltages on Wear Performance of Plasma Electrolytic Borocarbonitriding Layer on Pure Iron

Plasma electrolytic borocarbonitriding (PEB/C/N) was successfully used to achieve ternary borocarbonitriding layer on industrial pure iron at the bath voltages of 340, 360V and 380V respectively.The morphology, composition, phase constituents and microhardness profiles of PEB/C/N layers were investigated.The influence of bath voltages on wear behaviors of PEB/C/N layers was evaluated by ball-disc friction and wear tester under dry sliding against ZrO2 ball, and their wear mechanism were analyzed.The results show that the thickness and maximum hardness of PEB/C/N layer on pure iron increase with the increase of bath voltage.After 1h discharge treatment at 380V, the boride layer and transition layer of the PEB/C/N sample reach 26μm and 34μm respectively, and the maximum microhardness of PEB/C/N layer can reach 2318HV.The wear rate of PEB/C/N layer is only 1/10 of that of the pure iron substrate.The friction coefficient and wear rate of pure iron are greatly reduced after the PEB/C/N surface treatment, but the friction coefficient and wear rate of PEB/C/N layer vary little under different bath voltages.