Quantitative reverse deformation arrangement based method for designing cast model

Abstract

The invention relates to a quantitative reverse deformation arrangement based method for designing a cast model, in particular to a finite element thermo-mechanical coupling calculated quantitative reverse deformation based method for designing a large cast model. The method comprises the following steps: firstly, establishing a finite element thermal stress model by comprehensively concerning influence of casting solidification, cooling, mold dismantling and cutting of a gating system and thermal treatment; and then, setting different relax coefficients of reverse deformation according to differences of cast structure characteristics and different regional restraint intensities, and carrying out reverse deformation treatment on the original model. The relax coefficients of reverse deformation are determined by stress level of a calculation node, the more the stress value is, the less the relax coefficient is. Aiming at the added model of reverse deformation, numerical simulation and iteration of the whole thermal treatment process are carried out to finally determine a reasonable size of the cast model and produce a uniform cast with proper machining allowance.

Description

technical field [0001] The invention relates to the field of casting model design, in particular to a casting model design method for quantitatively setting reverse deformation amount based on numerical simulation. Background technique [0002] There are thermal stress and phase change stress in the casting process. Due to the uneven wall thickness, complex shape and uneven force of the casting, deformation will inevitably occur, which will affect the dimensional accuracy of the casting. In recent years, more and more attention has been paid to the thermal stress and deformation of castings during the casting process, especially for complex structural parts. A lot of theoretical and numerical simulation studies on thermal stress and deformation have been carried out, but because the various processes in the casting production process: solidification, cooling, boxing, cutting gating system and heat treatment all affect the final shape of the casting, it is difficult to accura...

AI Technical Summary

Problems solved by technology

However, increasing the machining allowance will bring about increased energy consumption, low yield, and long follow-up machining, which not only greatly increases the production cost of the enterprise, but also does not meet the national energy-saving and consumption-reducing requirements.

[0003] At present, most thermal stress models only simulate the two stages of solidification and cooling, ignoring the influence of the subsequent processes of boxing, cutting off the gating system and heat treatment on thermal stress and deformation, and cannot accurately predict the casting process. Dimensional changes and remaining machining allowances before machining

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