期刊文献+
共找到4篇文章
< 1 >
每页显示 20 50 100
Determination of dynamic recrystallization parameter domains of Ni80A superalloy by enhanced processing maps 被引量:9
1
作者 Guo-zheng QUAN Qiao LIU +2 位作者 Jiang ZHAO Wei XIONG Rui-ju SHI 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2019年第7期1449-1464,共16页
The determination of intrinsic deformation parameters inducing grain refinement mechanism of dynamic recrystallization (DRX) contributes to the relative forming process design. For Ni80A superalloy, the processing map... The determination of intrinsic deformation parameters inducing grain refinement mechanism of dynamic recrystallization (DRX) contributes to the relative forming process design. For Ni80A superalloy, the processing maps were constructed by the derivation of the stress-strain data coming from a series of isothermal compression tests at temperatures of 1273^-1473 K and strain rates of 0.01-10 s^-1. According to the processing maps and microstructural validation, the deformation parameter windows with DRX mechanism were separated in an innovative deformation mechanism map. In addition, the deformation activation energy representing deformation energy barrier was introduced to further optimize such windows. Finally, the enhanced processing maps were constructed and the parameter domains corresponding to DRX mechanism and lower deformation barrier were determined as follows: at ε=0.3, domains: 1296-1350 K, 0.056-0.32 s^-1 and 1350-1375 K, 0.035-0.11 s^-1;at ε=0.5, domains: 1290-1348 K, 0.2-0.5 s^-1 and 1305-1370 K, 0.035-0.2 s^-1;at ε=0.7, domains: 1290-1355 K, 0.042-0.26 s^-1;at ε=0.9, domains: 1298-1348 K, 0.037-0.224 s^-1. 展开更多
关键词 nickel-based superalloy deformation activation energy processing map dynamic recrystallization
下载PDF
Oxidation behaviors of wrought nickel-based superalloys in various high temperature environments 被引量:9
2
作者 Changheui JANG Daejong KIM +3 位作者 Donghoon KIM Injin SAH Woo-Seog RYU Young-sung YOO 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第7期1524-1531,共8页
Oxidation characteristics of Alloy 617 and Haynes 230 at 900 oC in simulated helium environment,hot steam environment containing H2 as well as in air and pure helium conditions were investigated.Compared to air condit... Oxidation characteristics of Alloy 617 and Haynes 230 at 900 oC in simulated helium environment,hot steam environment containing H2 as well as in air and pure helium conditions were investigated.Compared to air condition,the oxidation rate of Alloy 617 was not significantly affected in helium and hot steam environments,while Haynes 230 showed lower oxidation rate in helium environment.On the other hand,the oxide morphology and structure of Alloy 617 were strongly affected by the environments,but those of Haynes 230 were less dependent on the environments.For Haynes 230,a Cr2O3 inner layer and a protective MnCr2O4 outer layer were formed in all environments,which contributed to the better oxidation resistance.As the mechanical properties,such as creep and tensile properties,were significantly affected by the oxidation behaviors,surface treatment methods to enhance oxidation resistance of these alloys should be developed. 展开更多
关键词 oxidation nickel-based superalloys very high temperature reactor (VHTR) impure helium hot steam
下载PDF
Study on Ultrahigh Cycle Fatigue Performance of GH4169 Nickel⁃Based Alloy at 650℃ 被引量:1
3
作者 SONG Zongxian QI Hao +4 位作者 WU Zhisheng CHEN Xin ZHAO Zhenjun WU Ruizhe LIAN Zheng 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2020年第6期970-978,共9页
The fatigue test between 10^5—10^9 cycles of GH4169 nickel‑based superalloy commonly used in aircraft engines is carried out by ultrasonic fatigue machine at 650℃.The S‑N curve is obtained and the fatigue fracture m... The fatigue test between 10^5—10^9 cycles of GH4169 nickel‑based superalloy commonly used in aircraft engines is carried out by ultrasonic fatigue machine at 650℃.The S‑N curve is obtained and the fatigue fracture morphology is observed.The fatigue S‑N curve presents a“step‑like”shape,with the first inflection point near 1×10^7 cycles and the second inflection point near 1×10^8 cycles.There is no engineering fatigue limit,and it still shows a downward trend after 107 or even 10^9 cycles.The crack initiation location is related to its life.Cracks are generated on the surface below 10^7 cycles,while it is inside above 10^7 cycles.The crack initiation source in the ultra‑high cycle fatigue at 650℃ is mainly the local intergranular fracture and casting defect of the matrix.In the phase of crack propagation,the mixed propagation of intergranular and cleavage is the main form. 展开更多
关键词 nickel‑based superalloy ultrahigh cycle fatigue crack initiation
下载PDF
Comparison of the very high cycle fatigue behaviors of INCONEL 718 with different loading frequencies 被引量:7
4
作者 ZHANG YangYang DUAN Zheng SHI HuiJi 《Science China Chemistry》 SCIE EI CAS 2013年第3期617-623,共7页
In order to clarify the differences of very high cycle fatigue(VHCF) behavior of nickel based superalloy IN718 with different loading frequencies,stress-controlled fatigue tests were carried out by using ultrasonic te... In order to clarify the differences of very high cycle fatigue(VHCF) behavior of nickel based superalloy IN718 with different loading frequencies,stress-controlled fatigue tests were carried out by using ultrasonic testing method(20 KHz) and rotary bending testing method(52.5 Hz),both at room temperatures,to establish stress versus cycles to failure(S-N) relationships.Results disclosed that cycles to failure at a given stress level increased with an increase of the applied frequency,i.e.,the higher frequency produced an upper shift of the S-N curves.Fractographic analysis suggested that crack initiation and propagation behaviors had large differences:cracks in low-frequency tests preferentially initiated from multiple sources on the specimen surface,while in high-frequency tests,cracks mostly originated from a unique source of subsurface inclusions.Subsequently,frequency-involved modeling was proposed,based on the damage accumulation theory,which could well illustrate qualitatively those comparisons due to different loading frequencies. 展开更多
关键词 frequency effect very high cycle fatigue IN718 superalloy
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部