摘要
以甲酰胺作为渗剂、氯化铵作为导电盐,配制电解液,以活塞环为阴极和不锈钢棒为阳极,对活塞环进行了液相等离子体电解渗氮(PEN)处理,并对处理后的活塞环表面渗氮改性层的结构、元素分布及相组成等特征进行了分析,探究了PEN工艺操作参数对改性层的硬度和摩擦学性能的影响。结果表明:在有机电解液体系下进行活塞环表面电解渗氮处理会同时渗入N、C两种元素,但以渗N为主;活塞环表面的PEN改性层由化合物层、扩散层和过渡层组成,改性层中N元素的含量由表及里逐渐降低;改性层的主要相组成为铁的氮化物Fe2-3N、Fe4N和铁的碳化物Fe3C等强化相;改性层的最大硬度可达基体硬度的3倍,且随工作电压提高、处理时间延长和频率降低而增大;摩擦试验表明活塞环试样经PEN处理后其摩擦因数会增大,但对工作电压、处理时间和频率等工艺参数进行合理控制,便能够通过提高活塞环表面硬度和储油能力来抑制因摩擦因数增大而导致的磨损率升高。
An electrolyte was prepared by using formamide as penetrant and NH4Cl as conductive salt.Piston rings were treated with plasma electrolytic nitriding technology in the electrolyte through working as cathode while a stainless steel rod serving as anode.The structure,element distribution and phase composition of the modified layer on the surface of the treated piston ring were analyzed,and the effects of process parameters such as working voltage,processing time and frequency on the hardness and tribological properties of the modified layer were investigated as well.The results show that the plasma electrolytic nitriding treatment on the surface of the piston ring under the organic electrolyte system will infiltrate N and C elements simultaneously,while the main element is nitrogen.The PEN modified layer on the surface of the piston ring is composed of compound layer,diffusion layer and transition layer.The content of the N element in the modified layer gradually decreases from the surface to the inside.The main phase compositions of the PEN modified layer are iron nitrides such as Fe2-3N,Fe4N and iron carbide Fe3C.The maximum hardness of the modified layer can reach 3 times which compared to the hardness of the substrate,and it increases with the increase of working voltage,processing time and the decline of the frequency.Furthermore,friction tests show that the friction coefficient of piston ring samples will increase after PEN treatment.However,increasing of wear rate which caused by the rise of friction coefficient can be weakened by improving the surface hardness and oil storage capacity of the piston ring through choosing appropriate process parameters such as working voltage,processing time,and frequency.
作者
朱宗宁
赵鸿岳
梅德清
赵卫东
陈晨
陶俊
ZHU Zongning;ZHAO Hongyue;MEI Deqing;ZHAO Weidong;CHEN Chen;TAO Jun(School of Automatic and Traffic Engineering,Jiangsu University,Zhenjiang 212013,China;Jiangsu Su Yang Package Company Limited by shares,Yangzhou 211400,China)
出处
《中国表面工程》
EI
CAS
CSCD
北大核心
2020年第5期47-55,共9页
China Surface Engineering
基金
江苏高校品牌专业建设工程资助项目(苏政发办[2014]82)
江苏省科技厅重点研发计划项目(BE2016139)
作者简介
通信作者:梅德清(1974—),男(汉),教授,博士,研究方向:发动机节能与排放控制,E-mail:meideqing@ujs.edu.cn
