A Model for Estimation of Mould Thermal Fatigue Life in Permanent Mould Casting

Abstract

In this study, using materials thermo-physical data and CAD/CAE techniques the thermal fatigue life of a permanent mould is estimated. 3D solid models of the mould-casting system consisted of a permanent mould made from grade 60 ductile iron and an aluminium 7% Si, 0.3 % Mg Casting alloy (A356) were constructed in a CAD system. After defining all boundary and initials conditions in a finite element environment a thermal solution of the permanent mould casting is achieved repeatedly for every cycle until the steady-state temperature change is reached. The elastic-plastic stress calculation is performed by using the thermal history obtained from the thermal analysis. At the end, the residual stresses are determined and used for the thermal fatigue life estimation. The results showed that using the proposed CAD/CAE techniques the fatigue life of a permanent mould can be estimated.

Modelling the effect of coating on the stresses and microstructure evolution in chill casting of wind turbine main shafts

“…The cost of the chill itself might be higher than the cost of the actual main shaft in terms of the price of the cast iron used. The most common reason for chill failure found in literature is thermal fatigue . During mould filling, the liquid metal will heat up the inside of the chill leading to compressive stresses that will be counteracted by tensile stresses further out in the mould.…”