1、材料科学基础 Fundamental of Materials,Prof: Tian Min Bo Tel: 62795426 ，62772851E-mail: Department of Material Science and Engineering Tsinghua University. Beijing 100084,Lesson fifteen,4.8 Twinning (I) Macroscopic Aspect,.Rules governing the change in length. Change in shape of a hemisphere with unit radi
2、us.before twinning:,Undistorted planes and directions.,Twin elements K1、1，K2、2,Rule for elongation or reduction of R.D. All R.D. in the region where K1 and K2 makes an obtuse (acute) angle will increase (reduce) its length after twinning.,.Application: take HCP for exampleSuppose: ,Examples and Discussions,Exercise,Thank you !,15,
