铸造技术2016，Vol.37Issue(9)：1903-1907,5.DOI:10.16410/j.issn1000-8365.2016.09.030
水平连铸球墨铸铁QT500-7等温淬火工艺的优化研究
Optimal Study on Austempering Process Parameters for Nodular Cast Iron QT500-7 Dense Bar
摘要
Abstract
In order to optimize the austempering process parameters of ductile cast iron QT500-7 dense bar produced by horizontal continuous casting,the effect of austenitizing temperature,austenitizing time,austempering temperature,austempering time on tensile strength and elongation of the dense bar was investigated by using traditional orthogonal test method.The results indicate that austempering temperature is the most principal factor that affect the tensile strength of the austempered ductile cast.iron (ADI).Whereas,the elongation of the ADI is mainly controlled by austempering temperature and austempering time,especially by the former.With increasing austempering temperature,the volume fraction of ferrite decreases,significant coarsening of both ferrite and austenite grains occurs,consequently the tensile strength decreases and the elongation increases.The tensile strength of the ADI can be as high as 1 580 MPa after the dense bar is initially austenitized at 880 ℃ for 60 min and then quickly quenched to the 280 ℃ salt bath for 150 min and then air cooled.Whereas,when the dense bar is austenitized at 960 ℃ for 120 min and quenched into molten salt bath maintained at 360 ℃ for 125 min and then air cooled,the elongation of 11.9 ％ can be obtained.关键词
连续铸造/球墨铸铁/等温淬火/正交试验/力学性能Key words
continuous casting/ductile cast iron/austempering treatment/orthogonal test/mechanical property分类
矿业与冶金引用本文复制引用
黄继强,薛龙,张忠明,来东,李齐龙,徐春杰..水平连铸球墨铸铁QT500-7等温淬火工艺的优化研究[J].铸造技术,2016,37(9):1903-1907,5.基金项目
国家自然科学基金资助项目(51275051) （51275051）
光机电装备技术北京市重点实验室开放课题基金资助项目(KF2013-01) （KF2013-01）
