Tian Baohong

(School of Material Science and Engineering, Henan University of Science and Technology, Luoyang 471003)

Xu Binshi  Ma Shining  Liu Shican  Liang Xiubing

(Department of Material Science and Engineering, Armored Forces Engineering Institute, Beijing 100072)

Abstract: The numerical models of temperature and flight velocity of atomized droplets for high velocity arc spray (HVAS) process are established with dual-phase hydrodynamics and aerodynamics. The processing parameters, such as wire diameter, wire feed velocity, electric current, voltage, atomized gas pressure, etc, are correlated with the temperature, size distribution and flight velocity of atomized droplets. The established numerical simulation models reveal the influence of the HVAS processing parameters on the characteristic of atomized droplets. The numerical simulation results show that the flight velocity of the atomized 3Cr13 stainless steel droplets changes slightly during the practical spraying distance. The size of droplets has great effect on the original temperature. The superheats of different droplets size vary from 1 320 K to 2 090 K. The electrical resistance item has the highest effect on the superheat. The mass loss of the sprayed material during the arc spray processing is mainly due to the strong overheating of the droplets. The numerical simulation results go well with the measured results. The numerical simulated mass average size of HVAS sprayed 3Cr13 stainless steel is matched with that of the measured, while both of them have different features of size distribution.

Key words: High velocity arc spray  Temperature of droplet  Flight velocity  Numerical simulation

CLC No: TG706  TG174.44

国家自然科学基金资助项目(50005024). Received 20040728, received in revised form 20041230