In order to study the end face deformation and liquid film vaporization characteristics of mechanical face seal at medium and high temperature,a computational model involving vapor and liquid two-phase flow and seal ring deformation was established.Taking spiral groove liquid mechanical seal as an example,the axial deformation characteristics of seal end face under different medium temperatures were studied,and the influence of lubrication film pressure,temperature and vaporization characteristics on the end face deformation was studied.The results show that the maximum and minimum axial deformation of the moving ring are located near the inner diameter side of the weir area on the windward side and in the middle of the leeward side of the spiral groove.The axial deformation of the trough weir area shows the circumferential wavy change.The deformation of sealing face leads to the rise of film pressure and film temperature in dam area,and the degree of liquid film vaporization in weir area is obviously increased.When the temperature of the medium increases,the temperature of the lubricating film increases obviously and the opening force decreases,the degree of vaporization in the dam area remains low,and the degree of vaporization in the weir area increases obviously.When the temperature of the medium reaches 393 K,the growth rate of the degree of vaporization increases obviously,that is,the temperature of the medium with a sudden increase in vaporization exists.The overall degree of vaporization of lubrication film decreases with the increase of rotating speed.