New Chemistries for Metal Matrix Composites

在这个研究项目中，新的合成方法将被用于实现由激光粉末床熔合（LPBF）制成的合金和金属基复合材料（MMCs）的新的体化学和表面化学。在LPBF方法中，金属部件本质上是用金属粉末的激光3D打印的，允许创建具有复杂形状和性能的金属部件，否则无法实现。然而，LPBF零件的组成受到用于制造金属粉末的喷雾雾化方法的限制。此外，尽管非常理想，但铝的表面化学性质使铝基合金成为LPBF最难加工的合金之一。需要新的化学来解决这些问题。用金属基复合材料（MMCs）制造LPBF部件也是非常理想的，其中在合金中加入了增强陶瓷颗粒。mmc在飞机和汽车的轻量化结构部件中非常有用，可以提高燃油经济性。然而，mmc通常与LPBF方法不兼容。在这个研究计划中，新的合成方法将被用于显著提高LPBF方法得到的合金的化学成分。这项研究是由Obrovac实验室最近开发的干燥颗粒微粒化技术实现的，它可以将球磨粉末转化为光滑的球形粉末，其形态与LPBF兼容。此外，可以在颗粒中引入表面涂层、内部成分梯度甚至陶瓷增强颗粒。这使得LPBF中可以使用各种合金基体化学物质、表面化学物质和增强化学物质，从而进一步使新型mmc能够通过该工艺制造出来。颗粒形态的精确控制，独立于颗粒组成，也允许LPBF过程的化学基础研究。这些新方法从未应用于合金的合成。本研究项目将结合本体合金化学、表面化学、合金合成和纳米级颗粒设计，为学生提供丰富而宝贵的训练经验。这项研究计划的成果是使用成分和微观结构生产新的合金部件，否则由于成本，颗粒流动特性差或安全问题而受到阻碍。这将大大有利于环境和加拿大的汽车和航空航天工业提供廉价和轻质高强度的零件；从而降低成本，提高燃油经济性，提高电动汽车的行驶里程。

In this research program new synthesis methods will be used to enable new bulk and surface chemistries of alloys and metal matrix composites (MMCs) made by laser powder bed fusion (LPBF). In the LPBF method, metal parts are essentially 3D printed with a laser from metal powders, allowing the creation of metal parts with complex shapes and with properties not otherwise attainable. However, the composition of LPBF parts is limited by the spray atomization method used to make metal powders. In addition, although highly desirable, the surface chemistry of Al makes Al-based alloys amongst the most difficult to process by LPBF. New chemistries are required to solve these issues. It would also be highly desirable to make LPBF parts from metal matrix composites (MMCs), in which reinforcing ceramic particles are incorporated in the alloy. MMCs are highly useful for lightweight structural components to increase fuel economy in aircraft and automobiles. However, MMCs are generally incompatible with LPBF methods. In this research program new synthesis methods will be used to significantly increase the chemical compositions of alloys obtainable by the LPBF method. This research is enabled by dry particle microgranulation, recently developed in the Obrovac lab, which can convert ball milled powders into smooth, spherical powders with morphologies that are compatible with LPBF. In addition, surface coatings, internal composition gradients and even ceramic reinforcing particles may be introduced into the particles. This enables a wide variety of alloy matrix chemistries, surface chemistries and reinforcing chemistries to be used in LPBF, further enabling new MMCs to be made by this process. The precise control of particle morphology, independent of particle composition, also allows fundamental studies of the chemistry of the LPBF process. These new methods have never been applied to the synthesis of alloys. This research program will combine bulk alloy chemistry, surface chemistry, alloy synthesis, and nano-scale particle design, giving students a rich and valuable training experience. Outcomes of this research program are the production of new alloy parts using compositions and microstructures that have been otherwise hindered because of cost, poor particle flow characteristics or safety issues. This could greatly benefit the environment and Canadian automotive and aerospace industries by providing inexpensive and lightweight high strength parts; thereby reducing cost, improving fuel economy and improving the range of EVs.