Remanufacturing Of Laser-based Three-dimensional Coaxial Powder Work Head

Laser refabrication is a kind of new green reconstruction technology that based on laser cladding. It can be used to repair important weared parts rapidly, so it may bring the reducing production cost and saving working time. 3D coaxial feeding head is the most important and key part in laser refabrication. Many problems of interactions between laser and materials were involved in. It is significant and valuable to carry through the research of 3D coaxial feeding head deeply.In this paper, technical principles of laser refabrication were introduced. Current states of development were summarized in China and other countries. Model of the heated particles, model of division of the laser energy and concentration of powder stream were presented. Interaction between powder particles and laser was analyzed deeply. New 3D coaxial feeding head with adjustable of the powder stream focus was designed. DPIV(Digital Particle Image Velocimetry) technology was used to observe velocity fields and concentration fields of powder streams. A series of processing tests using 3D coaxial feeding head were carried out. Using 3D coaxial feeding head, large area laser refabrication was carried out in metallic sheath and stainless steel plates. The influence of the technological parameters to powder utilization ratio and quality of cladding were analyzed.It is shown that the 3D coaxial feeding head has the characteristic of full-direction and adjustable focus of powder stream.Major technical parameters of 3D coaxial feeding head: Focus model: lens focus/reflection focusFeeding model: carrying gas/without gasRotational angle of Φ axis: 0° -360°Rotational angle of ψ axis: -60 °--+60°Powder utilization ratio: feeding with carry gas >30%feeding without gas >60%...