检索结果-南通市图书馆

Microstructural changes during heating of super duplex stainless steel and its thermal deformation behavior

在线全文

学校读者我要写书评

暂无评论

引用

Baosteel Technical Research 2017年第4期11卷 22-33页

作者： ZHOU Candong AO Ying LIU Xiaorong Research Institute Baoshan Iron&Steel Co.Ltd.Shanghai 201900China

Microstructural changes during heating of highly alloyed Cr26Ni7 type super duplex stainless steel （SDSS2607） and its thermal deformation behavior were investigated. At different heating rates, the mechanism of phase transition from y phase to 6 phase and growth modes of ~ phase differed. Variations in microstructures for as- cast SDSS2607 during heat preservation at 1 220 ~C indicated two kinds of transformations from y phase to 6 phase. In-situ observations of microstructural changes during the tensile process at 1 050 showed a mutual coordination between y and 6 phases. When the true strain increased, the mutual coordination between 7 and 6 phases was damaged. Subsequently, cracks nucleated at the ＂y/g interface. With the increase in temperature, the strength of as- cast SDSS2607 decreased while its plasticity increased. Its thermoplasticity was poor, and the reduction in area of tensile specimens was less than 80%. When the deformation strain of hot compression increased, the stable deformation zone in the heat processing maps enlarged gradually. Moreover, the unstable deformation zones were extended.

关键词： super duplex stainless steel microstructural changes thermal deformation behavior

Research on the properties and microstructures of 27Cr-7Ni-4Mo super duplex stainless steel

在线全文

学校读者我要写书评

暂无评论

引用

Baosteel Technical Research 2016年第3期10卷 35-41页

作者： PENG Shidan LIU Xiaorong ZHOU Candong Baosteel Special steel Co. Ltd. Research Institute Baoshan Iron & Steel Co.Ltd.

In this study, metallographic analysis and nanoindentation characterization were used to analyze the properties and microstructures of as-cast nitrogen alloyed 27Cr-7Ni-4Mo super duplex stainless steel （super-DSS）. The as-cast microstructure of the super-DSS was characterized by its ferrite and island-like austenite phases. During the solution annealing process, the austenite volume percentage of the steel decreased gradually with increased annealing temperature. As a main element, the chromium content in the ferritic and austenitic phases elevated slightly at first then decreased with increased annealing temperature. The chromium partition coefficient in the steel varied by around 1.0. The contents of nickel, another main alloy element, also increased in the ferritic and austenitic phases with increased annealing temperature, as did the nickel partition coefficient in the steel, which tended to be close to 1.0. The nanoindentation characterization results indicate that the hardness of the austenite phase is slightly greater than that of the ferrite phase. They were similar to each other within a certain temperature range from 1 050 ℃ to 1 100℃. This temperature range was consistent with the temperature range in which the content ratio of the two phases was close to 1： 1. We found the Young＇ s modulus of the ferrite phase to be greater than that of the austenite phase. With increased annealing temperature, the Young＇ s modulus of the ferrite phase decreased while that of the austenite phase remained almost unchanged.

关键词： super duplex stainless steel nanoindentation characterization metallographic analysis

Crevice Corrosion of Several Supper stainless steels in the Simulated LT-MED Environment

在线全文

学校读者我要写书评

暂无评论

引用

Acta Metallurgica Sinica(English Letters) 2018年第11期31卷 1137-1147页

作者： Chang-Gang Wang Xiao-Fang Li Jie Wei Xin Wei Fang Xue Rong-Yao Ma Jun-Hua Dong Wei Ke Institute of Metal Research Chinese Academy of Sciences

Susceptibility and morphological characteristics of crevice corrosion for SS316, SS904L, SS254sMo and SS2507 in thesimulated low-temperature multi-effect distillation environment were investigated by cyclic polarization test, scanningelectron microscope and laser microscope. The results show that the crevice corrosion resistance of four kinds of stainlesssteel is ranked as SS254sMo ≈ SS2507 〉 SS316 〉 SS904L. There are ＂cover＂ structures over the edge of active crevicecorrosion regions of SS904L, SS254sMo and SS2507, but SS316 is an exception. Galvanic corrosion characteristicsappeared in the crevice of duplex supper stainless steel SS2507.

关键词： Supper austenite stainless steel super duplex stainless steel Low-temperature multi-effect distillation (LT-MED) Crevice corrosion "Cover" structure