Integrated Simulation of Castings Deformation during Casting and Heat Treatment Processes

Abstract

Deformation often appears in castings during casting and heat treatment processes, which determines the machining allowance setting and the machining size distribution of product. The paper presents a novel method for integrated simulation of the deformation behavior of castings during casting and heat treatment processes with a unified finite element model. Firstly, analyze the deformation of castings during casting process with the model containing mold and casting, and update the geometry of casting after casting process, then analyze the deformation of castings during heat treatment process and the final geometry shape of casting before machining could be obtained. By the method, investigation on the deformation behavior of a hydro turbine blade casting during casting and heat treatment processes was carried out, and the residual stress distribution and geometry shape of the casting were obtained.

Surface temperature difference for analysis of distortion of heavy weak-rigidity castings during heat treatment

“…Most research studied the thermal field, stress field, 5,6 phase transformation, deformation, 7 variation, and distribution of microstructure and mechanical properties 8 of the heavy steel castings. An integrated simulation of the distortion behavior of a blade casting during the casting and heat treatment processes has been carried out using finite-element method by Yu et al 9 The final distortion of the blade casting after the heat treatment process has been calculated. Optimization of the heat treatment process is important for controlling the deformation of casting since it can reduce and avoid the possible repair welding and shape correction work, decrease the machining allowance, and shorten the production period.…”

“…Optimization of the heat treatment process is important for controlling the deformation of casting since it can reduce and avoid the possible repair welding and shape correction work, decrease the machining allowance, and shorten the production period. However, the heat transfer coefficients on casting surfaces were assumed to be uniform, [6][7][8][9] which is not realistic in the actual process under the forced air cooling. A three-dimensional finite-element model to calculate the air speed and pressure distribution in air quenching furnace has been developed by Macchion et al, 10 and Xiao et al 11 studied the variations of heat transfer coefficient with respect to air temperature, air humidity, air velocity, and part orientation by a quenching system and series of experiments.…”