Microstructure and Carbides Characteristics of Spray Formed 9V High Vanadium Steels  

作　　者：徐轶 GUO Biao GE Changchun 

机构地区：[1]School of Materials Science & Engineering, Southwest Jiaotong University, Chengdu 610031, China [2]School of Materials Science and Engineering, Xihua University, Chengdu 610039, China [3]Institute of Special Ceramics and Powder Metallurgy, University of Science and Technology Beijing, Beijing 100083, China

出　　处：《Journal of Wuhan University of Technology(Materials Science)》2016年第4期896-902,共7页武汉理工大学学报（材料科学英文版）

基　　金：Funded by the National Natural Science Foundation of China(No.51301143);the National Postdoctoral Fundation of China(No.2014M560727);the Science and Technology Innovation Project of SWJTU University(No.2682014CX001);the Sichuan Province Science and Technology Support Program(CN)(No.2015GZ0228)

摘　　要：To develop advanced high speed steel with high vanadium content,a kind of vanadium content 9% high speed steel in the form of circular ring was spray formed under certain thermal conditions.The carbides topography of as-cast and as-sprayed 9V steel were observed.The effects of post thermo-mechanical processing（hot isostatic pressing and hot forging） and heat treatment on the microstructure and carbides distribution were investigated.The spray formed 9V steel typically consists of fine,homogeneous and angular-shaped MC carbides with diameters ranging from 1 to 2 μm.Spray formed 9V steel shows an excellent hot workability following increase of forging ratio due to fine homogeneous carbides.After heat treatment,spray formed 9V steel is composed of MC carbides,martensite and retained austenite.The hardness value of heat treated materials is inversely proportional to the volume fraction of residual austenite.Fine dispersed MC carbides have significant influences on the dislocation motion of spray formed 9V steel.To develop advanced high speed steel with high vanadium content,a kind of vanadium content 9% high speed steel in the form of circular ring was spray formed under certain thermal conditions.The carbides topography of as-cast and as-sprayed 9V steel were observed.The effects of post thermo-mechanical processing（hot isostatic pressing and hot forging） and heat treatment on the microstructure and carbides distribution were investigated.The spray formed 9V steel typically consists of fine,homogeneous and angular-shaped MC carbides with diameters ranging from 1 to 2 μm.Spray formed 9V steel shows an excellent hot workability following increase of forging ratio due to fine homogeneous carbides.After heat treatment,spray formed 9V steel is composed of MC carbides,martensite and retained austenite.The hardness value of heat treated materials is inversely proportional to the volume fraction of residual austenite.Fine dispersed MC carbides have significant influences on the dislocation motion of spray formed 9V steel.

关 键 词：spray martensite vanadium austenite forging hardness dispersed dislocation diameters pressing 

分 类 号：TG142.1[一般工业技术—材料科学与工程] TF124.39[金属学及工艺—金属材料]