The formation of sub-grain structure by alternating plastic strain
The formation of sub-grain structure by alternating plastic strain
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通过交替塑性应变形成亚晶结构
DOI：
10.1080/14786436108243331
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发表时间：
1961
影响因子：
1.6
通讯作者：
J. Holden
中科院分区：
文献类型：
--
作者：
J. Holden
摘要采用微束X射线技术对疲劳裂纹的断口进行了分析。裂纹在受到脉动张力的金属板中扩展，使得裂纹的增长速率与其瞬时长度成正比。断口显示出高度发达的亚晶结构，具有大于13°的大取向差。亚晶粒尺寸被认为是独立的范围内的循环应力用于传播裂纹和金属的特性。在大范围塑性应变ε 10−2的扭转试样中，亚晶结构的逐渐发展也随之而来。如果亚晶粒形成过程被视为疲劳裂纹扩展机制的一个基本特征，那么金属对疲劳裂纹扩展的敏感性顺序和非扩展表面裂纹现象就可以得到解释。
Abstract A micro-beam x-ray technique has been applied to the fracture surfaces produced by slow-growing fatigue cracks. The cracks were propagated in metal sheets subjected to pulsating tension such that the rate of growth of the crack was proportional to its instantaneous length. The fracture surfaces showed a highly developed sub-grain structure with large misorientations > 13°. The sub-grain size was found to be independent of the range of cyclic stress used to propagate the crack and to be characteristic of the metal. The progressive development of the sub-grain structure was followed in torsion specimens subjected to large ranges of plastic-strain ∼10−2. If the process of sub-grain formation is regarded as an essential feature of the mechanism of fatigue crack propagation then the order of susceptibility of metals to fatigue crack growth and the phenomenon of non-propagating surface cracks can be interpreted.