热处理工艺对SDP80C钢组织及性能的影响  

Influence of heat treatment process on microstructure and properties of SDP80C steel

作　　者：陈晟楠 彭睿智 吴晓春[1] Chen Shengnan;Peng Ruizhi;Wu Xiaochun(School of Materials Science and Engineering,Shanghai University,Shanghai 200072,China)

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》2025年第2期241-246,共6页Heat Treatment of Metals

基　　金：省部共建高品质特殊钢冶金与制备国家重点实验室自主课题(SKLASS 2022-Z12)。

摘　　要：利用热膨胀相变仪测定了预硬型压铸模具钢SDP80C的奥氏体连续冷却转变曲线,研究了不同时效工艺下的组织与力学性能。结果表明,SDP80C钢的马氏体开始转变温度(Ms)为320℃,奥氏体开始转变温度(Ac_(1))为695℃,奥氏体转变终了温度(Ac_(3))为841℃。在525~600℃时效温度范围内,时效温度的升高促进NiAl相和富Cu相的形成和生长,且马氏体组织发生回复,综合作用下SDP80C钢硬度逐渐降低,冲击性能得到提高。在525℃时效2 h后,由于纳米级NiAl相和富Cu相的析出强化,SDP80C钢达到最大硬度44.9 HRC,冲击吸收能量约为123 J。Austenite continuous cooling transformation curve of pre-hardened die casting steel SDP80C was measured by using a thermal dilatometer,and the microstructure and mechanical properties under different aging processes were studied.The results show that the martensitic transformation starting temperature(Ms)of the SDP80C steel is 320℃,the austenite transformation starting temperature(Ac_(1))is 695℃,and the austenite transformation ending temperature(Ac_(3))is 841℃.Within the aging temperature range of 525-600℃,the increase of aging temperature promotes the formation and growth of NiAl phase and Cu-rich phase,and the martensite recovers.As a result,the hardness of the SDP80C steel gradually decreases while the impact property improves.After aging at 525℃for 2 h,the SDP80C steel reaches the maximum hardness of 44.9 HRC and the impact absorbed energy is about 123 J,which is attribute to the precipitation strengthening of nano-scale NiAl phase and Cu-rich phase.

关 键 词：压铸模具钢SDP80C 时效工艺 硬度 冲击性能 NiAl相 

分 类 号：TG178[金属学及工艺—金属表面处理]