The effect of crystal orientation on the indentation response of commercially pure titanium: experiments and simulations
The effect of crystal orientation on the indentation response of commercially pure titanium: experiments and simulations
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DOI：
10.1098/rspa.2009.0455
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发表时间：
2010-03
期刊：
影响因子：
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通讯作者：
T. B. Britton;H. Liang;F. Dunne;A. Wilkinson
中科院分区：
文献类型：
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作者：
T. B. Britton;H. Liang;F. Dunne;A. Wilkinson
本文结合纳米压痕、电子背散射衍射（EBSD）和晶体塑性有限元分析，研究了α-Ti多晶内单个晶粒压痕行为的各向异性。纳米压痕是用来机械探测小体积的材料晶粒内的取向是已知的，从先前的EBSD映射。压痕模量和硬度随着压痕轴从c轴进一步倾斜而显着降低;塑性响应显示出更显着的各向异性。最近开发的高角分辨率EBSD已被用来检查选定的压痕，提供弹性应变变化和晶格旋转的地图。从这些地图的几何必要位错（GNDs）的密度下限的解决方案已经建立。晶体塑性建模显示的承诺，在正确捕获的方向依赖性的负载-位移响应和晶格旋转局部压头，特别是压痕到一个基面，产生三重旋转对称轴平行于压痕方向，这也是在实验中观察到的。
This study combines nanoindentation, electron backscatter diffraction (EBSD) and crystal plasticity finite element analysis to examine the anisotropy in the indentation behaviour of individual grains within an α-Ti polycrystal. Nanoindentation is utilized to mechanically probe small volumes of material within grains for which orientations are known from prior EBSD mapping. Both indentation modulus and hardness decrease significantly as the indentation axis is inclined further from the c-axis; the plastic response showing the more marked anisotropy. Recently developed high angular resolution EBSD has been utilized to examine selected indents, providing maps of elastic strain variations and lattice rotations. From such maps lower bound solutions for the density of geometrically necessary dislocations (GNDs) have been established. Crystal plasticity modelling showed promise in capturing correctly the orientation dependence of load–displacement response and in lattice rotations local to the indenter, particularly for indentation into a basal plane which generated threefold rotational symmetry about an axis parallel with the indentation direction which was also observed in experiments.