Influence of Alloy Elements on Cracking in the Steel Ingot during Its Solidification

Abstract

The average steepness of |dT/d(fs)1/2| on the T − (fs)1/2 curve were calculated during peritectic solidification, which was used to investigate the effect of alloying elements on surface longitudinal cracks of peritectic steels in the solidification process. The value of |dT/d(fs)1/2| indicates the liquid feeding capacity between interdendrites during solidification, where cracks can easily occur if there is poor capacity of liquid feeding, as in peritectic solidification shrinkage. The cracking tendency as a function of carbon content was well described by the |dT/d(fs)1/2| at the cooling rates of 0.5, 5, and 10 °C/s, and the influences of other solute elements on |dT/d(fs)1/2| were also calculated. The results indicate that the possibility of crack occurrence increased and the maximum average steepness |dT/d(fs)1/2| changed from 496.75 °C located near 0.09C wt.% to 622.14 °C near 0.11C wt.% with increasing cooling rate. The value of |dT/d(fs)1/2| on the T − (fs)1/2 curve during the peritectic solidification can be used to analyze the solidification crack for peritectic steels.

Keywords

• cracks susceptibility
• alloy elements
• peritectic steels
• solidification