摘要
采用真空热压技术制备了含有超高碳和铬(2.6%C,26%Cr,质量分数)的模具钢。基于差示扫描量热分析曲线,选取两个远低于熔点的温度(1100℃和1150℃)进行热压,分别制造出几乎完全致密、粉末之间冶金结合良好的块体钢,密度为7.45~7.47 g∙cm−3;对应热压温度1100℃和1150℃,热压态钢中平均碳化物尺寸分别为3.5μm和5.5μm,最大碳化物尺寸分别为6.0μm和8.5μm。经1150℃淬火、500℃回火,1100℃和1150℃热压钢的平均硬度分别为HRC 62.6和HRC 60.8,平均三点弯曲强度分别为2060 MPa和1850 MPa;经1150℃淬火、550℃回火,1100℃和1150℃热压钢硬度分别为HRC 55.2和HRC 53.6,平均三点弯曲强度分别为2490 MPa和2320 MPa。在相同淬火和回火条件下,1100℃热压钢的三点弯曲强度较高,原因是淬火回火后钢中碳化物尺寸较小。
Tool steels with the ultrahigh C and Cr(2.6%C and 26%Cr,mass fraction)were produced by the vacuum hot-pressing(VHP)in this study.Based on the differential scanning calorimetry analysis,two VHP temperatures(1100℃and 1150℃)are selected which are much lower than the melting point.The bulk steels with the density of 7.45~7.47 g∙cm−3 are obtained by VHP at 1100℃and 1150℃,respectively,exhibiting the full densification and good metallurgical bonding between powders.The average carbide sizes in the bulk steels obtained by VHP at 1100℃and 1150℃are 3.5μm and 5.5μm,and the maximum carbide sizes are 6.0μm and 8.5μm,respectively.After quenching at 1150℃and tempering at 500℃,the average hardness values of the bulk steels obtained by VHP at 1100℃and 1150℃are approximately HRC 62.6 and HRC 60.8,and the average three-point bending strengths are 2060 MPa and 1850 MPa,respectively.After quenching at 1150℃and tempering at 550℃,the average hardness values of the bulk steels obtained by VHP at 1100℃and 1150℃are approximately HRC 55.2 and HRC 53.6,and the average three-point bending strengths are 2490 MPa and 2320 MPa,respectively.At the same quenching and tempering conditions,the higher three-point bending strengths of the bulk steels obtained by VHP at 1100℃can be attributed to the smaller carbide sizes.
作者
邱悦
林耀军
张覃轶
陈斐
张岳香
QIU Yue;LIN Yao-jun;ZHANG Qin-yi;CHEN Fei;ZHANG Yue-xiang(School of Materials Science and Engineering,Wuhan University of Technology,Wuhan 430070,China;Beijing Huiyue New Material Technology Co.Ltd.,Beijing 102206,China)
出处
《粉末冶金技术》
CAS
CSCD
北大核心
2021年第4期297-303,325,共8页
Powder Metallurgy Technology
关键词
真空热压
粉末冶金
高碳高铬
模具钢
碳化物
vacuum hot-pressing
powder metallurgy
high carbon and high chromium
tool steels
carbides
作者简介
通信作者:林耀军,E-mail:yjlin@whut.edu.cn。
