Omnidirectional Supersonic Laser Deposition

冷喷涂（CS）是一种涂层和增材制造工艺，固体粉末颗粒在超音速气流中通过喷嘴加速到高达1000米/秒的速度，然后撞击基材，在那里它们结合形成涂层。由于其固态沉积和低热量输入到涂层或部件表面的优势，CS的市场占有率正在不断增长。目前使用冷喷涂的限制包括所生产的涂层的机械性能和可以不使用氦气沉积的材料范围，这将使该过程不经济。超音速激光沉积（SLD）是对冷喷涂的一种增强，在冷喷涂中，使用激光加热沉积部位，软化基材，改善粘合并扩大可沉积材料的范围。包括堆焊合金和难熔金属。虽然该工艺已受到包括航空航天、发电和消费电子等各个领域的跨国公司的极大兴趣，但当前SLD系统中激光和粉末流的固定相对位置限制了SLD在复杂形状上沉积的能力，同时缺乏对激光位置的反馈控制意味着该工艺不稳定。该项目的主要目标是通过实施以下措施来解决这些问题：*光束偏转系统可以将激光光斑放置在粉末足迹周围360°的任何位置，并实现多向沉积。*一个高度传感系统，将监测喷嘴的僵局，因此激光的位置，在实时。*控制系统将使用对峙数据自动调整光束偏转，并保持粉末足迹和激光的相对位置，同时涂层复杂的表面。

Cold Spray (CS) is a coating and additive manufacturing process where solid powder particles are accelerated through a nozzle in a supersonic gas stream to velocities of up to 1000 m/s before impacting a substrate where they bond to form a coating. CS is seeing growing market uptake due to its advantages of solid-state deposition and low heat input into the surfaces being coated or parts being built. Current limitations on the use of cold spray include the mechanical properties of the coatings produced and range of materials which can be deposited without resorting to the use of helium gas which will make the process uneconomical.Supersonic Laser Deposition, SLD, is an enhancement of cold spray where the deposition site is warmed using a laser, softening the substrate, improving bonding and widening the range of materials which can be deposited.to include hardfacing alloys and refractory metals.While the process has received significant interest from multinational companies operating in a variety of sectors including aerospace, power generation and consumer electronics, the fixed relative positions of laser and powder stream in current SLD systems limits the ability of SLD to deposit over complex shapes while the lack of feedback control on laser position means the process is not robust.The key objectives of the project are to address these issues by implementing the following:* A beam deflection system to place the laser spot anywhere in 360° around the powder footprint and enable multidirectional deposition.* A height sensing system which will monitor nozzle stand-off, and therefore laser position, in real time.* A control system which will use standoff data to automatically adjust beam deflection and maintain the relative positions of the powder footprint and laser while coating complex surfaces.