In this study, a functionally graded material (FGM) was fabricated using a powder bed fusion additive manufacturing technique. The FGM evaluated was Ti–6Al–4V, due to its importance in the medical device and aerospace sectors. The microstructure at selected build locations was analysed using both scanning electron microscopy (SEM) and electron backscatter diffraction (EBSD) techniques, where a gradient was observed both in terms of grain morphology and texture intensity. In addition, nanoindentation on the FGM sample shows a near quadratic shaped smooth gradient elastic modulus profile, with peak values at the midpoint of the gauge length. A tensile test to failure was conducted on the FGM sample with the aid of digital image correlation for surface strain analysis. Results show a gradient of local maximum principal strain in the highly {0001} textured section, while the reference sample in the control group shows a near-uniform strain distribution throughout the whole gauge length. A crystal plasticity finite element (CPFE) model was developed to explain the effect of texture on the mechanical properties adopting the microscopy-informed texture intensity gradient. Despite exhibiting higher elastic modulus (in the transverse direction, as measured via nanoindentation) the mid-section of the gauge length had a higher concentration of strain when loaded in the axial tensile direction, corresponding to build direction. The microscopy and computational modelling show that this apparent contradiction was explained via a high intensity of {0001} texture in the mid-section, leading to favourable conditions for axial strain accumulation.

在这项研究中，使用粉末床融合增材制造技术制造了功能梯度材料 (FGM)。评估的 FGM 是 Ti-6Al-4V，因为它在医疗设备和航空航天领域很重要。使用扫描电子显微镜 (SEM) 和电子背散射衍射 (EBSD) 技术分析选定构建位置的微观结构，其中在晶粒形态和纹理强度方面均观察到梯度。此外，FGM 样品上的纳米压痕显示出接近二次形状的平滑梯度弹性模量分布，峰值位于标距的中点。借助用于表面应变分析的数字图像相关性，对 FGM 样品进行了失效拉伸试验。结果显示在高度 {0001} 纹理部分中局部最大主应变的梯度，而对照组中的参考样品在整个标距长度上显示出接近均匀的应变分布。开发了晶体塑性有限元（CPFE）模型来解释纹理对采用显微镜通知的纹理强度梯度的机械性能的影响。尽管表现出更高的弹性模量（在横向上，通过纳米压痕测量），当在轴向拉伸方向上加载时，标距的中间部分具有更高的应变集中，对应于构建方向。显微镜和计算模型表明，这种明显的矛盾是通过中间部分的高强度 {0001} 纹理来解释的，