YAO Kefu TANG Naiyong CHEN Nanping Tsinghua University
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Beijing
,
China [Originally published in ACTA METALL SIN(CHINESE EDN)25(3)1989 pp A213—A218
,
Ph.D.Student
,
Dept.of Materials Sci.and Eng.
,
Tsinghua University
,
Beijing
,
China
金属学报(英文版)
The development of dislocation structures in the plastic zone ahead of a crack tip has been in- vestigated in a duplex stainless steel during in-situ deformation experiments in a scanning transmission electron microscope.It was found that the dislocation distribution was significantly different in the ferrite and in the austenite.In the ferrite grains,the dislocations emitted by the crack tip may cross-slip out of the original slip planes and form a broad plastic zone.However,in the austenite,the dislocation free zone is small and the dislocations emitted by the crack pile up in its slip plane.The selection of slip systems at the crack tip depends on the crack tip Schmid factors in both phases.But after large deformation,the selection of the second slip systems at the craek tip in austenite does not depend on the Schmid factors.
关键词:
crack tip
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null
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null
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null
伍展文
,
李洁
,
阳运国
,
黎松林
,
郑东宁
低温物理学报
利用脉冲激光沉积（PLD）方法制备了La213Ca1／3MnO3（LCMO）外延薄膜．然后利用微纳米加工技术对LCMO薄膜材料进行了局部改造，制造出宽度仅为83纳米的弱联接结构，并对此进行了一系列的物性改变研究．发现在测量电流不变（1μA）的情况下，R～T曲线在120K附近有一个尖锐的跳变，跳变的温度区间很窄．此外，测量电流和外加磁场的增加，都能对跳变现象产生抑制作用．目前认为这种现象的产生是由于相分离的原因导致的．
关键词:
脉冲激光沉积
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微纳米加工
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相分离
王甲安
,
李剑平
,
李建
,
戴斌
,
张锦文
,
石岩
材料热处理学报
通过宏观检查、化学成分、力学性能、显微组织及扫描电镜与能谱分析,结合设计、制造、安装等阶段存在的隐患分析,深入研究了某电厂SA213-TP347H高温再热器管频繁爆管原因.结果表明:高温再热器管子在弯管处存在不同程度的机械损伤缺陷.爆管管样化学成分、硬度、拉伸性能符合ASTM A213/A213M的规定;爆口处显微组织为奥氏体,晶界处存在含Cr和Nb成分析出物.备品备件硬度偏高,显微组织有明显的孪晶和较多滑移线,加速了敏化,晶界急剧贫Cr化.综上分析,高再频繁爆管的原因既有设计上的因素,也有制造质量的影响,而弯管未进行固溶处理,加速了贫Cr区的形成从而导致晶界抗腐蚀性能降低,导致晶间腐蚀所引起.
关键词:
SA-213-TP347H钢
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爆管
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制造质量
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固溶处理
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晶间腐蚀
