New Shining new light on laser additive manufacturing of powders using synchrotron imaging

增材制造（AM）被誉为最具颠覆性的技术之一，因为它彻底背离了铸造、热机械加工、机加工和连接等传统制造方法。这种潜在的变革性技术，允许前所未有的设计自由度，允许在激光功率的帮助下从粉末中逐层构建组件。塑料3D打印在医疗和工程原型应用方面已经取得了巨大的成功。然而，使用AM的大规模金属合金组件生产仅进入少数利基市场，其中之一是医疗植入物，包括钛关节置换（超过10万例患者），这得益于Lee教授团队的发展。在航空航天应用中，由于通过更有效的部件拓扑设计消除了大规模的加工浪费和最小的材料使用，AM有望产生重大的经济影响。然而，了解和控制激光加工的粉末微观结构是材料科学在极端-非常高的凝固速率，超细微观结构和远离平衡的亚稳相形成的典范。我们迫切需要实验和建模的敏锐性来推动该领域的发展，从而产生新的发明。这些极端的加工条件是实施和快速使用AM进行金属/合金部件制造的挑战的核心。它是材料制造的一个快速发展的分支，充满了令人兴奋的问题，需要一系列先进的设备和表征技术。曼彻斯特在开发用于在激光粉末增材制造过程中直接观察熔池的原位同步加速器表征技术方面处于世界领先地位，并开发了第一台进行此类实验的装置。在博士期间，学生将首先在新材料/条件下使用现有的钻机，然后帮助开发第二代钻机用于替代工艺，如吹制粉末激光AM。他们将联合收割机这种独特的能力与更传统的显微镜（光学和EM）和机械测试技术相结合。他们还将进行相关的光学和热成像，并与谢菲尔德的学生合作，使用新购买的300万英镑灵活的研究AM机器扩大新的基本见解。

Additive Manufacturing (AM) is hailed as one of the top disruptive technologies as it is a radical departure from the traditional manufacturing approaches of casting, thermomechanical processing, machining and joining. This potentially transformative technology, allowing unprecedented design freedom, allows components to be built layer by layer from powder aided by laser power. Tremendous success has already been achieved by 3D-printing using plastics for medical and engineering prototype applications. However, large-scale alloy component production in metals using AM has only broken into a few niche markets, one of them medical implants, including the titanium joint replacements (over 100,000 are in patients) aided by developments in Prof. Lee's group. In aerospace applications, AM promises to have a significant economic impact due to elimination of large-scale machining wastage and minimal usage of material via more efficient topological designs of components. However, understanding and controlling laser-processed powder microstructures is an exemplar for materials science at extreme - very high solidification rates, ultra-fine microstructures, and far-from-equilibrium meta-stable phase formation. There is a critical need for both experimental and modelling acumen to advance the field, resulting in new inventions.These extreme processing conditions lie at the heart of the challenge to implement and readily use AM for metal/alloy component manufacturing. It is a rapidly evolving branch of materials manufacturing, rich in exciting problems and demanding an array of advanced equipment and characterization techniques. Manchester is world leading in developing in situ synchrotron characterisation techniques for directly observing the molten pool during laser powder AM, having developed the first rig to perform such experiments. During the PhD the student will first use this existing rig on new materials / conditions, and then help develop a second generation rig for alternative processes such as blown powder laser AM. They will combine this unique capability with more traditional microscopy (optical and EM) and mechanical testing techniques. They will also perform correlative optical and thermal imaging, and working collaboratively with students at Sheffield, scale up the new fundamental insights using the £3m in newly purchased flexible research AM machines there.