殷为民
,
郭建亭
,
胡壮麒
材料研究学报
近年来,金属间化合物Fe_3Al 合金由于具有高强度、耐腐蚀、低密度和低成本等一系列优点而受到世界各国材料科学工作者的普遍重视,开展了大量的研究工作,获得了许多基本数据,取得了很多有规律的结果。本文对国外在Fe_3Al 方面发表的大量文献和作者近两年开展的工作进行综合评述,主要内容包括相结构和晶体缺陷;物理和力学性能;合金脆性以及组织结构和力学性能等方面。
关键词:
晶体结构
,
superdislocation
,
corrosion resistance
,
Fe_3Al
,
mechanical properties
W.H. Tian*
金属学报(英文版)
A transmission electron microscopy (TEM) investigation has been performed on the dislocation pinning in L12-ordered Ni3(Al,Ti) containing disordered γ precipitates. The morphology of defor?鄄mation induced dislocations in the γ' base alloys containing fine dispersion of disordered γ was investigated by means of weak-beam electron microscopy. The superdislocations are strongly at?鄄tracted to the disordered particles and dissociate on the (111) plane in the γ particles, while they dissociate on the (010) plane in the γ' matrix. The disordered γ precipitates play an important role as a pinning point during the cross-slip of superdislocations from (111) to (010) planes in the γ' matrix and restrain the cross-slip of superdislocations. The interaction of superdislocations with disordered particles causes the formation of superkinks, jogs and closed loops.
关键词:
superdislocation
,
precipitates
,
attractiv
徐文臣
,
单德彬
,
张浩
金属学报
doi:10.3724/SP.J.1037.2013.00470
在热模拟试验机上进行高温压缩实验,研究了含β相的Ti-42Al-9V-0.3Y合金的高温变形行为,分析了其不连续屈服行为的产生机理.研究表明,含β相的Ti-42Al-9V-0.3Y合金的主要热变形软化机制为β相的动态回复和γ相的动态再结晶,高温变形过程的不连续屈服行为与β相的动态回复和γ相中超位错(Burgers矢量b=1/2〈112〉)的增殖相关.基于Orowan方程建立的位错动力学模型可合理解释该合金不连续屈服的产生原因,证实可动位错密度的快速增加和低的位错速度应力敏感系数m*容易诱发TiAl合金的不连续屈服.合金在较低温度(1100-1150℃)和较高应变速率(1 s-1)下产生波动屈服归因于位错滑移和孪晶交互作用.
关键词:
TiAl合金
,
不连续屈服
,
动态软化
,
超位错
,
Orowan方程
