Mechanism of New Plasma Powder Surfacing for High Efficiency and High Quality

It is presented preliminary assessment of new plasma technology with both high deposition rate and low rate of dilution,which was developed under the calculation and analysis of compressive properties of plasma are, arc flame characteristics and kinematics behavior of poweder in the arc.Compared with normal plasma surfacing method,the idea using constricting nozzle with small orifice diameter, long plasma arc and increasing the distance from meeting point of two beams of powder to workpiece,to achieve the goals of high depoition rate and low rate of dilution, was put forward here first time.In order to prove this idea,a simple set of experimental system was built up and satisfied results including high deposition rate(more than 15 kg/h) and low rate of dilution (less than 1~5%) were obtained.The success of this study offer a promising prospect for developing the powder plasma hardfacing technology in China and may open a way to improve this technology further in efficiency and quality.