Improved metallurgical manufacture via multi-axial testing of microstructures

下一代冶金制造需要对金属和合金在多向载荷下如何变形有一个新的认识。该项目将通过开发用于扫描电子显微镜（SEM）内部原位研究的微型双轴机械测试设备来解决这一关键知识差距。材料的变形通常以其单轴试验特性为模型。然而，许多现代金属成形工艺使合金承受非常复杂的载荷。对多轴载荷下塑性变形的有限实际理解可能会对制造部件的几何形状施加限制。双轴测试为这些过程的复杂变形力学提供了有价值的见解。构建的微型荷载框架将用于研究选定的高性能结构合金的微结构级变形，以表征部件级变形。数字图像相关和晶体取向映射（电子反向散射衍射，EBSD）将用于测量变形在合金不同微观结构特征上的局部程度。这些研究将确定通过传统和增材制造技术生产的现代微结构复杂合金的单轴和双轴变形行为之间的区别。研究结果将为研究不同类型合金组织的变形提供新的理论依据。这些改进的模型将有助于开发和优化新型资源高效的金属成型和增材制造工艺，从而生产出具有优异结构完整性的更轻的部件。

Next-generation metallurgical manufacturing requires a new level of understanding of how metals and alloys deform under multi-directional loading. The project will address this critical knowledge gap by developing a miniature bi-axial mechanical testing apparatus for in-situ studies inside a scanning electron microscope (SEM). Deformation of materials is often modelled on their uniaxial test characteristics. However, many modern metal-forming processes subject alloys to very complex loading regimes. The limited practical understanding of plastic deformation under multi-axial loading can place constraints on the geometry of the manufactured components. Bi-axial testing provides valuable insight about the intricate deformation mechanics of these processes. The constructed miniature load-frame will be used to investigate microstructure-level deformation of selected high-performance structural alloys in order to characterise component-scale deformation. Digital image correlation and crystal orientation mapping (electron back-scatter diffraction, EBSD) will be used to measure the degree to which deformation is localised at the different microstructural features of the alloys. The studies will identify distinctions between uniaxial and bi-axial deformation behaviour in modern microstructurally complex alloys produced via conventional and additive manufacturing techniques. The results will be used to develop new theories for the deformation of different types of alloy microstructures. These improved models will enable the development and optimisation of novel resource-efficient metal-forming and additive manufacturing processes that produce lighter components with superior structural integrity.