J.M. Zhang
,
L.Z. Ma
,
J. Y. Zhuang
,
Q. Deng
,
J.H Du and Z. Y Zhong(Department of Superalloys
,
Central Iron & Steel Research Institute
,
Beijing 100081
,
China)P. Janschek(Thyssen Umformtechnik GMBH
,
42859 Remscheid
,
Germany Manuscript received 26 August 1996)
金属学报(英文版)
Isothermal constant speed compression tests of superalloy IN718 were conducted using a computer-controlled MTS machine at temperatures from 960 to 1040℃, with initial strain rates from 0.001 s~(1) to 1.0 s~(1) and engineering strain from 0.1 to 0. 7.The variations of flow stress with deformation temperature, initial strain rate and engineering strain were analyzed in the paper. It was found that there was an obvious power-law relationship between flow stress and initial strain rate, which showed the behavior of strain rate hardening of superalloy IN718 at elevated temperatures.The relationship between flow stress and temperature could be described by an inverse trigonometric function.And the turning point on the curve may be related to the behavior of δ phase at 1000℃. Meanwhile, it was found that there was a complicated relationship between flow stress and strain,which was indicative of the comprehensive effect of work hardening and dynamic softening on flow stress during hot deformation. From the results of these tests, a constitutive equation of superalloy IN718 was developed.
关键词:
: constitutive relationship
,
null
,
null
Ying Liy Changzhen Wang Zhongli Zhang Jiangxin Wang
材料科学技术（英文）
The steel contains a small amount of hydrogen which will escape during the heat treatment. The hydrogen pressure in 16MnRE steel was investigated with a hydrogen sensor, which used SrCe0:95Yb0:05O3-α proton conductor as a solid electrolyte, YHx+YH2-z as a solid state reference electrode and Ni wire as electrode constructing a hydrogen concentration cell, shown as Ni|YHx+YH2-z |SrCe0:95Yb0:05O3-α |[H]steel |Ni. The response time of sensor is less than 10 s. The relational expression of hydrogen partial pressure with temperatures was determined using two shape proton conductors. The results showed the regularity in experimental temperature range, and the hydrogen partial pressure increased as its temperature was raised.
关键词:
Hydrogen sensor
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Proton conductor
,
Solid electrolyte
WANG Fuhui LO U Hanyi BAI Linxiang Institute of Corrosion and Protection of Metals
,
Academia Sinica
,
Shenyang
,
China WANG Fuhui
,
Institute of Corrosion and Protection of Metals
,
Academia Sinica
,
Shenyang 110015
,
China
金属学报(英文版)
The yttraluminizing coating on the Ni-base superalloys has been developed by dipping the specimens in a specially made yttrium-containing slurry as an underlayer and over spraying a Cr-Al slurry as a protective layer,then heating to 1060℃ and holding for 1 h under argon atmosphere.Analysis by EPMA showed that the yttrium was concentrated in the intermediate zone of the coating as metallic compound Ni-5Y.After exposure to air up to 1000℃,the oxidation test revealed that the anti-oxidation resistance of the yttraluminizing coating with post-aluminizing is much superior to that with single aluminizing only.
关键词:
yttraluminizing coating
,
null
,
null
,
null
张立春
,
何安强
,
叶恒强
,
张永昌
材料研究学报
用HRTEM、TEM及EDAX分析研究了Al─Li—Cu—Mg—Zr合金中的一种新相(暂名H相)和六角Z相的结构,确定H相具有四方点阵,点阵参数为α=2.8nm,c=2.4nm,EDAX分析表明H相和Z相均含Al、Mg、Cu发现H相与Z相的共存取向关系为[100]‖[1120]Z,[1010]H‖[0001]Z。还观察到Z相中一种特有的旋转畴结构
关键词:
Al─Li─Cu─Mg─Zr合金.四方H相
,
tetragonal H phase
,
hexagonal Z phase
李虎
,
王作成
,
薛长深
,
庄栋栋
,
王晓
,
张思勋
材料热处理学报
为了研究钢中合金元素Nb、B、Ni对低合金高强度H型钢抗层状撕裂能力(Z向性能)的影响,设计了对照试验,通过常温下拉力试验,对其力学性能尤其是断面收缩率进行了测试,使用XRD、SEM、TEM以及EDS对其组织和成分进行了分析.结果表明:微合金元素Nb、B和微量元素Ni对钢材的Z向性能产生了明显的不良影响,含有Nb、B和Ni,经过钢包精炼的Q345E钢的Z向性能显著低于不含Nb、B和Ni,未经钢包精炼且含有较多夹杂物的Q345B钢.其原因主要在于Nb、B、Ni的存在阻碍了钢材变形过程中位错在晶界和晶内的移动.
关键词:
低合金高强度钢
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Z向性能
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合金元素
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夹杂物
,
阻碍位错
孙建春
,
盛光敏
,
陈登明
,
周安若
,
朱光俊
功能材料
1J50软磁合金的性能主要是通过H_2热处理获得的,在1130℃和H2气氛保护下对冷轧态1J50软磁合金进行了热处理.运用MATS-2010SA软磁测试仪对处理前后1J50软磁合金的磁性能进行了检测,运用金相显微镜、XRD等手段对处理前后1J50软磁合金的组织结构进行了分析.结果表明,通过H_2热处理,1J50软磁合金的矫顽力显著降低,起始磁导率和最大磁导率提高;组织结构发生明显变化,冷轧态1J50软磁合金组织为孪晶奥氏体,平均晶粒尺寸为200μm,处理过后,晶粒显著长大,平均晶粒尺寸为100μm;由于在600℃时采取了快冷,处理后1J50软磁合金中未出现大量FeNi相和FeNi_3相.
关键词:
H2热处理
,
1J50
,
组织结构
,
性能
何恩全
,
马文会
,
刘荣辉
,
于洁
,
戴永年
稀有金属
doi:10.3969/j.issn.0258-7076.2007.04.019
采用了甘氨酸-硝酸盐法制备了La0.7Sr0.3Cr0.5-yMn0.5-zCo(y+z)O3(y, z=0.1, 0.2)系列阳极材料.借助XRD, SEM对所制备的材料进行了物相和形貌分析.XRD表明利用GNP法制得的粉体在1350 ℃烧结5 h可以形成完整的钙钛矿相;SEM分析可知所得物料颗粒呈球状,尺寸约为1 μm,且没有团聚现象.同时,XRD显示La0.7Sr0.3Cr0.5Mn0.4Co0.1O3和La0.9Sr0.1Ga0.8Mg0.2O3电解质之间具有较好的化学相容性.采用直流四探针法测试了不同组成材料在250～800 ℃温度范围内在空气中的电导率,发现该系列材料在该温度段范围符合小极化子导电机制.另外,利用直流四探针法测试了La0.7Sr0.3Cr0.5Mn0.4Co0.1O3在不同还原气氛下的电导率,在CH4和H2气氛中,La0.7Sr0.3Cr0.5Mn0.4Co0.1O3最大电导率分别达到了4.5和0.42 S·cm-1.
关键词:
钙钛矿
,
阳极
,
电导率
Materials at High Temperatures
Two different ways of combining nitrogen in virgin and revert superalloy have been identified. The source of nitrogen in revert superalloy has been ascertained. It is found that nitrogen in scraps of virgin superalloy undergoes a transition from CrN to TiN when these scraps are remelted in VIM furnace. High nitrogen content in revert superalloys causes microporosity formation, that greatly deteriorates tensile and stress rupture properties of superalloys.
关键词:
nitrogen;revert superalloy;microporosity
Y.F.Gu
,
Y.Yamabe-Mitarai
,
C.Huang
,
H.Harada
金属学报(英文版)
It was proposed that a new class of alloys based on platinum group metals (PGMs) were calle drefractory superalloys. These refractory superalloys have an fcc and L12 coherent two-phase structure (similar to that of Ni-based superalloys), high melting temperatures and good potential as structural materials used at temperatures up to 1800℃. Our recent results on the microstructure evolution, deformation and fracture behavior of some of these refracotry superaUoys, especial lr- and Rh-base refractory superalloys were reported.
关键词:
platinum group metals
,
null
,
null
