On-the-fly control of laser additive manufacturing

激光增材制造使用紧密聚焦的激光束在前体材料（如金属粉末）上扫描，逐层“写入”3D金属部件，允许直接从计算机绘图中创建轻量化设计。 尽管激光增材制造是一个价值数十亿美元的行业，正在经历指数级增长，但由于缺乏原位质量保证技术，其广泛采用受到阻碍。 解决质量保证/控制问题将对加拿大工业及其在汽车、航空航天和医疗设备制造等竞争激烈的行业中的创新能力具有关键的战略意义。我们将利用加拿大发明的一种新型相干成像技术，直接对激光写入过程进行高速成像。 除了为每个3D像素提供直接的质量保证外，我们还将使用我们的新技术来闭合反馈回路，以允许对工艺参数进行实时补偿，从而实现目标构图。 错误将在写入时被擦除。 这将减少故障，并有可能打开新的几何形状，写入技术和材料目前不可能由于激光写入过程的固有随机性。该项目的成果包括：i）在对加拿大先进制造业至关重要的领域培训9名学生/研究人员，ii）减少新组件工艺开发时间，iii）通过实时控制实现新的设计范例，以及iv）提高对高功率激光束尖端发生的潜在物理学的理解。

Laser additive manufacturing uses a tightly focused laser beam scanned over a precursor material (such as metal powder) to "write" a 3D metal component layer by layer, allowing the creation of lightweight designs directly from a computer drawing. Even though laser additive manufacturing is a billion dollar industry undergoing exponential growth, its widespread adoption is being impeded by lack of an in situ quality assurance technique. Solving the QA/control problem will be of key strategic importance for Canadian industry and their ability to innovate in highly competitive industries, such as automotive, aerospace and medical device manufacturing. We will exploit a novel coherent imaging technique invented in Canada to directly high-speed image the laser writing process while it is happening. In addition to providing direct quality assurance for every 3D pixel, we will use our new technology to close the feedback loop to allow on-the-fly compensation of process parameters to achieve the targeted composition. Errors will be erased as they are written. This will reduce failures and has the potential to open the door to novel geometries, writing techniques and materials currently not possible due to the inherent randomness of the laser writing process. Outcomes of this project include: i) training of nine students/researchers in a field of key important to Canadian advanced manufacturing, ii) reduction of novel component process development time, iii) novel design paradigms enabled by on-the-fly control, and iv) improved understanding of the underlying physics happening at the tip of a high power laser beam.