铌微合金钢析出相的形成与长大规律  

Formation and growth rules of participate in niobium micro-alloyed steel

作　　者：吴静[1] 张恒华[1] 

机构地区：[1]上海大学材料科学与工程学院,上海200072

出　　处：《金属热处理》2011年第4期4-7,共4页Heat Treatment of Metals

基　　金：先进钢铁材料技术国家研究工程中心项目(D09-0110-07-005)

摘　　要：将铌微合金钢在1200℃固溶2 h,然后分别在700℃时效5、15、30和60 min。利用显微硬度计和电阻仪,结合三维原子探针研究了铌微合金钢中析出相的萌生规律及其对硬度和电阻率的影响。结果表明,层片状的NbC团簇在700℃时效5 min时已经形成,团簇尺寸随着时效时间的延长而增大。当时效时间为30 min时,团簇数量密度达到最大值。在30 min前,细小碳化物使得显微硬度值上升、电阻率下降。而当时效时间超过30 min,碳化物以长大为主,碳化物粗化使得硬度值下降、电阻率上升。The initiating rules of carbide in niobium micro-alloyed steel solid solution treated at 1200 ℃ for 2 h then aged at 700 ℃ for 5,15,30 and 60 min were investigated by three dimensional atom probe combined with microhardness tester and resistance meter.The results show that cluster with a few nanometers is a plate-like morphology,which initiates at 700 ℃ within 5 min.The cluster becomes larger as aging time enlongated,and the number density reaches the maximum at 30 min.Microhardness increases and electrical resistivity decreases before 30 min.Carbides mainly grow after 30 min,and coarsed carbides make the microhardness decrease and the electrical resistivity increase.

关 键 词：微合金钢 固溶时效 电阻率 三维原子探针 含Nb碳化物析出 

分 类 号：TG142.33[一般工业技术—材料科学与工程]