LIU Zhonghao CHEN Lian Institute of Metal Research
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Academia Sinica
,
Shenyang
,
China
金属学报(英文版)
Within the range of 77 to 295 K,the strength and plastieity of 18Ni maraging steel increase with decreasing temperature and decrease with increasing hydrogen content.The susceptibility to hydrogen embrittlement of the maraged specimens is superior to solid solution ones.The dislocations after plastically deforming will tangle into dislocation cells which reduce thermselves in size as the temperature decreases,and coarsen as the hydrogen content in- creases.No cryogenie deformation twin was found.The tensile fracture surfaces of the solu- tion and maraged specimens containing 5.90 ppm hydrogen under 295 to 223 K are revealed as quasi-cleavage and intergranular features respectively and as transgranular ones under other experimental conditions.The influence of hydrogen on the mechanical behaviour of steel and the mechanism of hydrogen induced deformation and fracture are discussed. Research Assistant, Institute of Metal Research,Academia Sinica, Shenyang 110015,China
关键词:
maraging steel
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null
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null
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null
陈建刚
,
张建福
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卢凤双
,
张敬霖
,
张建生
金属功能材料
18Ni马氏体时效钢是以无碳(或超低碳)铁镍马氏体为基体的,主要是经时效产生时效强化的高强度钢.本文简要概述了18Ni马氏体时效钢的发展过程,介绍了固溶强化、相变强化、时效强化、细晶强化、形变强化方法和发展趋势.
关键词:
马氏体时效钢
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强化方法
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固溶强化
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相变强化
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时效强化
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细晶强化
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形变强化
YIN Zhongda Harbin Institute of Technology
,
Harbin
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China ZHOU Yongkang Shanghai Centrifugal Machinery Research Institute
,
Shanghai
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China YIN Zhongda Faculty of Heat Treatment of Materials
,
Harbin Institute of Technology
,
Harbin 150006
,
China
金属学报(英文版)
An approach to study the recrystallization-induced plasticity(RIP)phenomenon in the 18Ni maraging steel under the elastic stress has been made by the analysis of dynamic behaviour at elevated temperatures,the phenomenological analysis of dynamic strain feature curves,the confirmation of phase transformation point and TEM observation of RIP processing itself.
关键词:
elastic stress
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null
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null
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null
YAO Daping CHEN Wenxiu Institute of Metal Research
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Academia Sinica Wenhua Rd.
,
Shenyang.110015
,
China
材料科学技术(英文)
An investigation of the phenomenon of hydrogen trapping at grain boundaries in 18 Ni maraging steel has been carried out by the thermal hydrogen evolution technique.Grain boundary on- ly acts as a trapping site of hydrogen at low temper- ature region,and the peak of its hydrogen evolution from it is observed at 405K with 3.00K/rain heat- ing rate and with specimen of 0.55mm thick.The trap activation energy of hydrogen escaped from grain boundary is estimated as 14.2kJ/mol. Hydrogen trapping at grain boundary is mainly as sociated with segregated hydrogen by impurities, and its behaviour is primarily the interaction be- tween hydrogen and the hydrostatic stress field of the grain boundary.
关键词:
hydrogen trapping
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null
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null
王志浩
,
郭伟国
,
郭今
,
刘开业
材料科学与工程学报
针对马氏体时效钢18Ni(250)在动态拉伸和不同速度泰勒杆冲击下呈现剪切断裂破坏的特征,为了理解其剪切及Ⅱ型断裂韧性在复合型断裂中所起到的作用,借助Hopkinson拉杆装置,对18Ni(250)进行了高加载率下的复合受力试验.并根据该材料在不同加载率下剪切断裂模式的特征,重点对该材料进行了不同加载率下的Ⅱ型动态断裂韧性试验研究.结果表明:随着加载率的提高,18Ni(250)钢的起裂时间逐渐减小,但其Ⅱ型动态断裂韧性值不断增大;通过SEM微观分析发现,在不同加载率下18Ni(250)钢Ⅱ型动态断裂呈现以晶面滑移为主的绝热剪切特性.
关键词:
马氏体时效钢
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剪切断裂
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加载率
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Ⅱ型断裂
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泰勒试验