基于超声技术的FDM无支撑悬浮打印基础研究

为了提高3D打印制造效率，降低成本，提高制件表面质量，减少或实现无支撑打印是一个重要解决方法。但现有的“无支撑”打印仍属工艺结构优化范畴，尚未见纯粹的无支撑悬空打印报道。本项目基于超声波悬浮原理，结合熔融沉积方法（FDM），进行无支撑悬浮3D打印基础理论研究。设计多相阵声场，解决连续送进丝材的悬浮保持性，进而设置边界条件，建立悬浮稳定性理论模型；搭建FDM悬浮打印实验平台，热像仪跟踪热场以分析其对声辐射力影响，解耦打印环境动态热场与声悬浮场之间的协调关系；采用高速相机抓拍丝材在声场中形态变化，结合材料物性，分析并确定连续丝材表面在不均匀声辐射压下的形变及性变规律。研究结果一方面将打破3D打印必须加支撑的思维定势，真正从原理上实现无支撑打印；另一方面为未来空间立体曲面打印的实现提供理论支持，具有重要的理论意义和应用价值。

It is an important solution for 3D printing to reduce supporting or remove supporting, which can improve its manufacturing efficiency, reduce the cost and improve the surface quality of the parts. But the existing 3D printing without support is still a category of structure optimization, the report for pure unsupported printing has not been seen. This project is based on the principle of ultrasonic levitation and combined with molten deposition method (FDM) to study the basic theory for unsupported levitation 3D printing. Multi-phased array acoustic field is build to solve the levitation retention of feeding wire, and the boundary conditions are set to establish the levitation stability theory model of feeding wire; An FDM experimental platform is build for levitation printing. The influence of thermal field on acoustic radiation force is analyzed using thermal imager, which can track the change of heat in the platform. The coordination relationship between dynamic thermal field and acoustic levitation field is decoupled. A high speed camera is used to capture the shape change of the wire in the acoustic field. The deformation and performance change law of feeding wire surface is determined by analyzing the captured images and material property. On the one hand, the research results will break the thinking set that 3D printing must be added supporting, and realize the 3D printing without support in principle. On the other hand, the results will provide theoretical support for the future spatial stereoscopic surface printing, which has important theoretical significance and application value.