Stress Releasement by Transformation Superplasticity(Part 3). The Effect of Applied Stress on Elongation during Transformation.
Stress Releasement by Transformation Superplasticity(Part 3). The Effect of Applied Stress on Elongation during Transformation.
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通过转变超塑性释放应力（第 3 部分）。
DOI：
10.2207/qjjws.11.167
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发表时间：
1993
期刊：
影响因子：
--
通讯作者：
H. Tamura
中科院分区：
文献类型：
--
作者：
Hirotaka Murata;N. Kato;H. Tamura
前人的研究表明，在一定条件下，相变超塑性比相变膨胀更能有效地降低形变应力，并且在冷却过程中的形变应力与相变温度有关。为了阐明相变超塑性的基本行为，本文研究了恒定应力下相变过程中试件的伸长率。结果表明：1)相变过程中，试件受到1 Mpa量级的小应力的塑性变形；2)超塑性相变产生的位移与相变过程中施加的应力成正比。3)当强度恢复模取R，变形强度(σ)记为σ=er时，R约为9.0~16.6 Gpa，是杨氏模数的1/10~1/20倍。4)在室温马氏体相变拉伸试验中，试件发生塑性变形的断裂应力不到断裂应力的1/4，通过施加热缩数量级的小应力产生马氏体。然后观察了马氏体区的表面起伏。
In the previou study, it was shown that transformation superplasticity was more effective to reduce the deformation stress than transformation expansion under some conditions and the transformation temperature was concerned in the deformation stress in the midst of cooling.In the present report, the elongation of specimen was invesigated during transformation at a constant stress in order to clarify the basic behaviour of transfomation superplasticity.The results are shown as follows ;1) During transformation a specimen was plastically distored by a small stress of the order of 1 MPa.2) The displacement by superplasticity transformation is in proportion to the applied stress during transformation. The inclination, however, varied with materials.3) If the strength restoration module is taken as R and the deformation strength (σ) is writen as σ=eR, R was about 9.0-16.6 GPa that was 1/10-1/20 times as much as Young's module.4) In the tensile test of the specimen during martensite transformation at room temperature, the specimen was plastically distored by less than quarter of the fracture stress and the strain by applying a small stress of the order of thermal contraction gave rise to martensite. Then the surface relief by martensite was observed.