丙烷浓度对45钢离子碳氮共渗的影响  

Plasma Nitrocarburization of AISI 1045 Steel Surfaces with Propane

作　　者：叶雪梅[1] 武计强 朱永利[1] 胡静[1] 

机构地区：[1]常州大学江苏省材料表面科学与技术重点实验室,常州213164

出　　处：《真空科学与技术学报》2015年第5期580-583,共4页Chinese Journal of Vacuum Science and Technology

基　　金：江苏省研究生创新基金项目;江苏高校优势学科建设工程资助项目

摘　　要：首次以丙烷作为供碳剂对45钢进行离子碳氮共渗。利用金相显微镜、X射线衍射仪和显微硬度计研究了丙烷浓度对试样截面形貌、物相组成和表面硬度的影响。结果表明:随丙烷浓度的增加,化合物层厚度和表面硬度均呈现先增大后减小的趋势。当丙烷浓度为1.5%时,510℃离子碳氮共渗4h后,化合物层厚度和表面硬度分别达到最大值40μm和779HV0.05,同时得到以ε相为主,并伴有极少量渗碳体的最优物相组成。当丙烷浓度超过1.5%时,化合物层厚度和表面硬度均下降,这是由于渗碳体相含量随丙烷的增加而增加,并当丙烷浓度为2.5%时渗碳体成为主要物相,从而阻碍了C、N原子向基体内的进一步扩渗。A novel technique was developed,for the first time,to plasma nitrocarburize AISI steel with propane as the carbon source because of its low ionization energy.The impact of the propane concentration on the microstructures and properties of the nitrocarburized surfaces was investigated with X-ray diffraction,metallurgical microscope and conventional mechanical probes.The results show that the propane concentration significantly affects the formation of desirableε-phase and mechanical properties of the modified surfaces.For instance,as the propane concentration increased,the hardness and thickness changed in an increase-decrease mode.Modified at 510℃ for 4h with 1.5% propane,the maximum layer thickness and hardness were 40μm and 779HV0.05,respectively.The dominance ofε-phased nitride,coexisting with little cementite,was observed.A propane concentration higher than 1.5%resulted in decreases of the thickness and hardness but an increase of cementite phase.However,the dominance of cementite phase,formed with2.5% propane,prevented C and N atoms from diffusing into the substrate.

关 键 词：丙烷 离子碳氮共渗 显微组织 45钢 

分 类 号：TG156.8[金属学及工艺—热处理]