反复镦拔SIMA法制备100Cr6钢半固态坯料的工艺与组织  

Preparation technology and microstructure of 100Cr6 steel semi-solid billet by SIMA method with repeated upsetting-stretching

作　　者：肖良红[1,2,3] 郑文 樊星[1,3] 黄顺其 XIAO Liang-hong;ZHENG Wen;FAN Xing;HUANG Shun-qi(School of Mechanical Engineering,Xiangtan University,Xiangtan 411105,China;Engineering Research Center of Complex'Tracks Processing'Technology and Equipment of Ministry of Education,Xiangtan University,Xiangtan 411105,China;Key Laboratory of Welding Robot and Application Technology of Hunan Province,Xiangtan University,Xiangtan 411105,China)

机构地区：[1]湘潭大学机械工程学院,湖南湘潭411105 [2]湘潭大学复杂轨迹加工工艺及装备教育部工程研究中心,湖南湘潭411105 [3]湘潭大学焊接机器人与应用技术湖南省重点实验室,湖南湘潭411105

出　　处：《塑性工程学报》2020年第10期13-20,共8页Journal of Plasticity Engineering

基　　金：湘潭大学博士启动基金资助项目(12QDZ17)。

摘　　要：利用多道次反复镦拔预塑性变形和半固态等温处理工艺(反复镦拔与等温处理SIMA法)制备了100Cr6钢半固态坯料,对100Cr6钢细化晶粒的反复镦拔预变形工艺和后续的等温处理工艺及其微观组织分别进行了研究。结果表明:反复镦拔预变形可以有效利用塑性变形破碎枝晶而达到细化晶粒的目的,从未预变形(镦拔0次)到镦拔3次,晶粒直径先快速减小然后变化不大;当反复镦拔3次时,试样中心的晶粒直径减小了90.4%,即从未经预变形的晶粒直径Φ274.1μm细化到Φ26.2μm;而试样边缘的晶粒直径减小了91.7%,细化效果更佳。在半固态温度区间进行等温处理时,随着温度的增加,半固态坯料的晶粒逐渐近球化;随保温时间的增长,半固态坯料的晶粒逐渐变大;尺寸为Φ10 mm×15 mm的试样在1420℃下保温30 min等温处理后所得半固态组织相对较好。The semi-solid billets of 100 Cr6 steel were prepared by multi-pass repeated upsetting-stretching pre-plastic deformation and semisolid isothermal treatment process(repeated upsetting-stretching and isothermal treatment SIMA method).The repeated upsetting-stretching pre-deformation process for grain refinement and the subsequent isothermal treatment process,as well as the microstructure of 100 Cr6 steel after pre-deformation and isothermal treatment were studied respectively.The results show that the repeated upsetting-stretching pre-deformation can effectively utilize plastic deformation to break up dendrites and refine grains.From no pre-deformation(upsetting-stretching zero time)to upsetting-stretching three times,the grain diameter first decreases rapidly and then changes little.When the repeated upsettingstretching is carried out three times,the grain diameter in sample center decreases by 90.4%,namely the grain diameter decreases fromΦ274.1μm(no pre-deformation)toΦ26.2μm.However,the grain diameter of the sample edge decreases by 91.7%,and the refining effect is better.During isothermal treatment in the semi-solid temperature range,with the increase of temperature,the grain of semi-solid billet gradually approximates to spheroidization.As the holding time increases,the grain of semi-solid billet gradually becomes larger.The semi-solid structure of theΦ10 mm×15 mm sample is relatively good after isothermal treatment at 1420℃for 30 min.

关 键 词：镦拔 SIMA法 100Cr6钢 半固态坯料 晶粒组织 

分 类 号：TG113[金属学及工艺—物理冶金]