A method to calculate the heat transfer coefficient is proposed by using finite element software combined with experimental calculation that is based on measured temperature curves

carrying out the nonlinear coupling on various factors which have influence on the heat transfer coefficient of U75V rail steel (/% : 0. 74C

0. 76Si

0. 82Mn

0. 014P

0. 028S

0. 071V)

the geometric model of the heat transfer coefficient of steel in quenching process is established and the heat transfer coefficient is obtained by iterative program of calculated heat transfer coefficient prepared with Python language. Using calculated heat transfer coefficient as a known boundary conditions

the simulation on temperature field of rail spray quenching coupled with phase transition in the DEFORM-3 D is carried out. The simulated-calculation cooling-curve corresponds to the measured cooling curve.