GOALI/FSI/Postdoctoral Industrial Fellowship: Damage Evolution During Manufacturing of Advanced Materials -- Experiments and Modelling

9510572莱万多夫斯基在这个GOALI项目中，一名博士后研究员在一个工业合作伙伴的网站上工作，合作进行与先进材料加工相关的基础研究。本研究选用的复合材料为非连续增强铝合金。Focus的加工步骤是二次操作，损伤是由于颗粒的大小和分布、基质的微观结构和应力状态造成的。为了评估足够广泛的加工条件和增强体尺寸，将生产平均颗粒尺寸为5um、15um和50um的不连续增强铝(DRA)，并将其挤压到1：2-1：20的挤压比，以研究颗粒尺寸和工艺参数对部件制造过程中损伤演变的影响以及这些影响与部件最终性能的关系。微结构损伤的程度将通过测量弹性模量和泊松比演化，以及通过对抛光截面上的裂纹颗粒和其他损伤进行定量评估来评估。与在工业现场进行工作的实验计划并行，该大学将开发一个使用蒙特卡罗模拟方法的简单模型，以预测通过微观损伤的结合在最终部件中产生重大缺陷的可能性。这项研究对于了解伴随着各种工艺条件的组织结构和性能变化的演变，从而有助于制造可靠的DRA部件将是必不可少的。使用连续纤维增强材料的先进复合材料目前被用于军用飞机和体育用品等利基应用。虽然连续纤维要求进行专门的加工，但非连续纤维提供了以最小的资本影响适应传统加工的机会。这项研究的成功完成，有可能将复合材料的用途扩展到汽车和其他大批量应用。此外，通过支持学术界的研究人员在行业环境中生活和呼吸，可以实现研究和实践之间的更大合作。

9510572 Lewandowski In this GOALI project, one postdoctoral researcher works at the site of an industrial partner to collaborate on fundamental research related to advanced materials processing. The composite material chosen for this study is discontinuously reinforced aluminum alloy. The processing step for focus is secondary operations and the damage accrued as a result of particle size and distribution, matrix microstructure and the stress state. In order to assess a sufficiently broad range of processing conditions and reinforcement sizes, discontinuously reinforced aluminum (DRA) with average particle sizes of 5um, 15um and 50um will be produced and extruded to extrusion ratios of 1:2 - 1:20 to study the effects of particle size and processing parameters on the evolution of damage during manufacturing of a component as well as to relate these to the final properties of the component. The level of microstructural damage will be evaluated through measurements of elastic modulus and poisson ratio evolution, as well as by quantitative evaluation of cracked particles and other damage on polished sections. In parallel with the experimental program where work is carried out at the industrial site, a simple model using Monte Carlo simulation approach will be developed at the university to predict the probability of significantly large defects arising in the final components via coalescence of the micro damage. This study will be essential in understanding of the evolution of microstructures and property changes which accompany various processing conditions and thereby aid in the manufacturing of reliable DRA components. Advanced composites using continuous fiber reinforced materials are currently used in niche applications such as military aircrafts and sporting goods. While continuous fibers mandate specialized processing, discontinuous fibers offers the opportunity to fit into conventional processing with minimum capital implications. Successful completion of this research has the po tential to expand the composite use into automotive and other high volume applications. Further, by supporting a researcher from academe to live and breathe in the industry setting, a greater collaboration between research and practice may be realized.