热等静压UNS S32750超级双相不锈钢的组织和性能  

Microstructure and properties of UNS S32750 super-duplex stainless steels processed by hot isostatic pressing

作　　者：尚峰 王智勇 乔斌 贺毅强 李化强 SHANG Feng;WANG Zhi-yong;QIAO Bin;HE Yi-qiang;LI Hua-qiang(School of Mechanical and Engineering,Jiangsu Ocean University,Lianyungang 222005,China)

机构地区：[1]江苏海洋大学机械工程学院,连云港222005

出　　处：《粉末冶金技术》2022年第6期483-487,共5页Powder Metallurgy Technology

基　　金：江苏省高校“青蓝工程”中青年学术带头人资助项目;江苏省“六大人才高峰”高层次人才资助项目;江苏省“333”人才工程资助项目;江苏省产学研前瞻性联合研究项目(BY2018210);淮海工学院自然科学基金(Z2017001);连云港市521人才工程项目(ZKK201805);连云港市海燕计划(2018-QD-013)。

摘　　要：采用等离子旋转电极雾化-热等静压工艺制备了UNS S32750超级双相不锈钢。利用光学显微镜、扫描电子显微镜、电子背散射衍射、万能试验机等手段研究了热等静压UNS S32750超级双相不锈钢固溶处理前后的显微组织和力学性能。结果表明:采用等离子旋转电极雾化制备的UNS S32750超级双相不锈钢粉末在150 MPa压力下,经1200℃×3 h热等静压烧结后实现了致密化,相对密度为99.7%。随炉缓冷过程中,烧结件中析出的σ相导致材料韧性显著下降。经1035℃×1 h固溶处理后水淬,σ相完全溶解,材料韧性显著提高,显微组织为α和γ两相组织,体积比为65:35,抗拉强度791 MPa,屈服强度586 MPa,断后伸长率38%,冲击吸收功236 J。The UNS S32750 super-duplex stainless steels were prepared by plasma rotating electrode processing and hot isostatic pressing in this study.The microstructure and mechanical properties of the steels before and after the solution treatment were investigated by optical microscope(OM),scanning electron microscope(SEM),electron back scattering diffraction(EBSD),and electronic material testing machine.The results indicate that the UNS S32750 super-duplex stainless steel powders prepared by plasma rotary electrode processing can be densified by hot isostatic pressing sintering at 1200℃for 3 h at 150 MPa,and the relative density of the sintered parts is 99.7%.Theσphases precipitate in the sintered parts during the furnace slow cooling process,significantly undermining the impact toughness.In contrast,theσphases are dissolved completely after the solution treatment at 1035℃for 1 hfollowed by the water quenching,leading to a notable increase in the impact toughness.A duplex structure of theαandγphases is identified,which significantly affects the properties of the specimens.In detail,the volume ratio between theαandγphases is 65:35,the tensile strength and yield strength of the specimens are 791 MPa and 586 MPa,respectively,the elongation is approximately 38%,and the impact absorbing energy is 236 J.

关 键 词：等离子旋转电极雾化 热等静压 超级双相不锈钢 显微组织 力学性能 

分 类 号：TG142.1[一般工业技术—材料科学与工程]