The anisotropic behaviour of laser powder bed fusion (LPBF) Ti-6Al-4V under uniaxial tension is investigated through crystal plasticity simulations. A periodic multi-scale representative volume element (RVE) is calibrated against quasi-static tensile tests carried out on dog-bone specimens, printed in different orientations. This fitting procedure results in an anisotropic crystallographic texture and a minimum set of crystal plasticity constitutive parameters which are able to reproduce the experimental behaviour. The synthetic RVE consists of primary grains with a realistic aspect ratio and an internal lamellar structure, that approximates the ${\alpha }^{\prime }$ martensite microstructure observed in micrographs of as-built Ti-6Al-4V. The Young’s modulus, yield strength, and hardening behaviour observed experimentally, could be precisely captured using a very limited number of model parameters. Thereby, this work contributes to a deeper understanding of the interplay between micro-structure and macroscopic behaviour, and with a new set of crystal plasticity parameters specific for ${\alpha }^{\prime }$ dominated LPBF Ti-6Al-4V.

通过晶体塑性模拟研究了激光粉末床融合 (LPBF) Ti-6Al-4V 在单轴拉伸下的各向异性行为。周期性的多尺度代表性体积元素 (RVE) 是针对在不同方向打印的狗骨样本上进行的准静态拉伸测试进行校准的。这种拟合程序导致各向异性晶体结构和能够重现实验行为的最小晶体塑性本构参数集。合成 RVE 由具有真实纵横比和内部层状结构的初级晶粒组成，近似于${\alpha }^{\prime }$在 Ti-6Al-4V 竣工显微照片中观察到的马氏体显微组织。通过实验观察到的杨氏模量、屈服强度和硬化行为，可以使用非常有限数量的模型参数精确捕获。因此，这项工作有助于更深入地了解微观结构和宏观行为之间的相互作用，并提供一组新的晶体塑性参数。${\alpha }^{\prime }$ LPBF Ti-6Al-4V 占主导地位。