项目名称： 中空激光光内复合送料熔覆光/粉/丝耦合、熔凝及成形基础研究

项目编号： No.61475107

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 无线电电子学、电信技术

项目作者： 傅戈雁

作者单位： 苏州大学

项目金额： 80万元

中文摘要： 基于中空激光变换，提出粉裹丝激光光内同轴复合送料金属熔覆成形新方法，兼具送粉熔覆柔性好、吸热快、熔道平整、堆高性好和送丝熔覆选材范围广、材料利用率高、成本低的优势，并可实现梯度制造。拟深入探讨中空激光束对 粉裹丝复合体相互作用的规律、机制和效应，粉末对光反射的屏蔽作用，粉末与丝材的吸能、传热规律，中心丝材的热岛效应；研究中空激光特有的光鞍效应对于粉/丝二体共熔-凝固的机制与影响因素、熔道表界面构形与边界热熔合机理，以及粉/丝复合材料三维成形机制；通过调节粉、丝流场控制材料成分，深入研究粉、丝流渐变与激光耦合的演变机制，获得梯度成形实体；建立激光光内复合送料光/粉/丝耦合温度场、流场及凝固应力场模型。本研究为激光熔覆增材制造，特别是大型、高性能致密金属零件或梯度功能件的直接成形提供新方法、新理论和新技术。

中文关键词： 激光熔覆；复合送粉送丝；中空激光；耦合；成形

英文摘要： Based on the hollow laser exchange by dual cone-cirque reflector mirrors, the laser cladding method of combining coaxial powder and wire feeding is applied to develop a new direct metal deposition technique. Its main characteristics is that the solid laser beam is transformed into the hollow laser beam and the powder wrapping the wire are delivered to the molten pool together from the inside of hollow laser beam. This new technique doesn't only combine the advantages of individual powder and wire feeding, but also overcomes their issues. What's more, it also improves the heat absorption rate, the penetration bead quality and forming efficiency, and controls the material gradient. In this study, the law , mechanism and effects of interactions among laser beam, powder and wire will be discussed, including the outside powder shielding effects to wire, the heat absorption and heat transfer of powder and wire to the laser beam, and the heat island effect of the wire. It will also be studied that the effect of saddle energy distribution of hollow laser to the mechanisms of the melting-solidification of powder and wire, the surface morphology and the fusion quality of the clad boundary, and physical 3-dimensional prototyping using powder-wire compound material. By adjusting the powder and wire flow field, the material gradient and its coupling mechanism with laser beam are designed to be controlled and researched. Numerical models of the thermal field, flow field and solidification stress field among powder, wire and laser beam will be established. This study will refine the research theory of material feeding by hollow laser beam and provides a new process and theoretical base for metal rapid deposition, especially for producing large dense metal components with high performance.

英文关键词： laser cladding;combining powder and wire feeding;hollow laser;coupling;forming