| Summary: | 碩士 === 國立成功大學 === 材料科學及工程學系 === 103 === Shear band considered as important effect in deformation texture, we use Taylor-based models to investigate texture evolution of Copper and Brass-type shear band in F.C.C. C-orientation (112)[11-1] single crystal. Taylor-based models combine with plane strain condition and four geometric models to simulate texture evolution of shear bands forming at different stack fault energy.
The results indicate before Copper-type shear bands forming, C-orientation rotates to D-orientation (4 4 11)[11 11 -8]. After shear bands forming, different geometric models make D-orientation rotate around ±TD from near (112)[-1-11] to (110)[00-1] according with experiments.
The results also show before Brass-type shear bands forming, C-orientation rotates to D-orientation and Twin-orientation (26 26 5)[-5 -5 52] which is activated twin system (111)[11-2]. So it can rotate whole structure 27˚ making twin-matrix layers parallel to RD, and then use matrix orientation (111)[11-2] to next stage. After shear bands forming, some geometric models make matrix orientation (111)[11-2] and twin orientation (111)[-1-12] rotate to (114)[22-1] and (110)[001]. Another models make matrix and twin orientation rotate to (110)[00-1] and(11-4)[221]. Both of them accord with experiments describing {111}〈112〉 transfers to {110}〈001〉 and {114}〈221〉.
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