碳含量对金属注射成形17-4PH不锈钢显微组织和力学性能的影响  

Effect of carbon content on microstructure and mechanical properties of metal injection molded 17-4PH stainless steel

作　　者：张翔[1] 何浩[1] 李益民[1] 刘晨 满露梅 胡幼华[1] 

机构地区：[1]中南大学粉末冶金国家重点实验室,长沙410083 [2]广西冶金研究院,南宁530023

出　　处：《中国有色金属学报》2015年第4期945-951,共7页The Chinese Journal of Nonferrous Metals

基　　金：湖南省自然科学基金资助项目(2015JJ3147);总装备部项目(303001042);广西科技攻关项目(14122007-22)

摘　　要：通过在喂料中添加石墨改变注射成形17-4PH不锈钢组织中的碳含量,研究不同碳含量对MIM 17-4PH显微组织和力学性能的影响。结果表明:在烧结态和固溶时效态试样中,碳含量少于0.16%(质量分数)的相组织主要由马氏体和少量的铁素体构成。随着碳含量的逐渐升高,冷却过程中奥氏体未能完全转变成马氏体,组织中出现奥氏体,在碳含量为0.16%的烧结态和固溶时效态试样中,其显微组织为马氏体和奥氏体共同组成的双相组织,而且奥氏体相含量随着碳含量增加而逐渐增加;在碳含量达到0.25%以上时,试样的显微组织完全转变为奥氏体,导致试样的表观硬度下降,抗拉强度下降,伸长率提高。Graphite was added into the 17-4PH stainless steel to vary the carbon content. The effect of carbon content on the microstructure and mechanical properties of metal injection molded 17-4PH stainless steel was investigated. The results show that the samples by solid solution and aging treatment, mainly consist of martensite and a small amount of ferrite at carbon content less than 0.16%. Austenite fails to completely transform into martensite in the cooling process and the amount of austenite increases gradually with the carbon content increasing. The samples consist of both martensite and austenite at carbon content of 0.16%. Then, the samples mainly consist of austenite when carbon content is more than 0.25%. This leads to a decrease in hardness and tensile strength, while the elongation increases.

关 键 词：MIM17-4PH不锈钢 碳含量 相转变 力学性能 

分 类 号：TG142.71[一般工业技术—材料科学与工程]