可控离子渗入(PIP)处理对25Cr2Ni4WA钢薄壁件力学性能的影响  

Effect of programable ion permeation(PIP)treatment on mechanical properties of 25Cr2Ni4WA steel thin-walled parts

作　　者：杨俊霞 罗德福[1] 陈赟鑫 谢周胜 Yang Junxia;Luo Defu;Chen Yunxin;Xie Zhousheng(College of Materials Science and Engineering,Xihua University,Chengdu Sichuan 610039,China)

机构地区：[1]西华大学材料科学与工程学院,四川成都610039

出　　处：《金属热处理》2024年第12期249-253,共5页Heat Treatment of Metals

摘　　要：采用可控离子渗入技术(Programmable ion permeation,PIP)对25Cr2Ni4WA钢厚度为2 mm的薄壁试样进行表面改性,主要工艺是渗氮温度530℃,氰酸根浓度32%,渗氮时间分别为20、40、60、90 min,渗氮后进行渗氧处理,渗氧温度450℃,渗氧时间15 min。对不同PIP工艺处理后的试样进行渗层组织显微形貌、表面硬度、截面硬度、拉伸性能、断口形貌进行分析。结果表明,渗层结构依次为氧化膜、疏松层、白亮层、扩散层;渗层厚度随着渗氮时间的延长而增厚,但是渗层增长速率会有所下降;PIP处理能明显提高试样的硬度,其中渗氮时间为60 min的试样硬度最高,是基体硬度的2.3倍;PIP处理后试样的拉伸性能有所下降,渗层深度越深,下降越多,试样整体呈韧性-脆性混合断裂。Surface modification of the 25Cr2Ni4WA steel specimens with thickness of 2 mm was carried out with programable ion permeation(PIP)technology.The main processes were nitriding temperature of 530℃,cyanate concentration of 32%,nitriding time of 20,40,60 and 90 min,respectively,and after nitriding,oxygenation treatment was carried out,with oxygenation temperature of 450℃and oxygenation time of 15 min.The microstructure,surface hardness,cross section hardness,tensile properties and fracture morphologies of the specimens treated by different PIP processes were analyzed.The results show that the structure of the permeation layer is composed of oxide film,loose layer,bright white layer and diffusion layer.The thickness of permeation layer increases with the extension of nitriding time,but the growth rate of infiltration layer decreases.PIP treatment can significantly improve the hardness of the specimens,in which the hardness of the specimens with nitriding time of 60 min is the highest and 2.3 times of the substrate one.After PIP treatment,the tensile properties of the specimens decrease,and the deeper the penetration layer,the more the decrease,and the specimens as a whole show ductile-brittle mixed fracture.

关 键 词：可控离子渗入技术(PIP) 渗氮工艺 显微组织 表面硬度 

分 类 号：TG156.8[金属学及工艺—热处理]