An Investigation on Formation Mechanisms of Wrinkles on Steel Casting Surfaces
The formation mechanisms of horizontal wrinkles and water wave wrinkles on steel casting surface have been investigated in this study. The horizontal wrinkles, which are the traces of rising steel flow overlapping, are caused by low pouring temperature and slow molten steel flow rising rate. The water wave wrinkles are resulted from the use of an alcohol-based refractory coating with poor permeability and strong penetration behavior. This coating may penetrate deeply into the pores of sand mold and are not easy to be dried by flame combustion. When pouring the alcohol containing in the coating will volatilize and generate a large amount of gas, forming a gas cushion at steel-mold interface. With the gas escapes gradually, the gas cushion disappears, leaving a gap between the steel and the mold, the solidifying casting surface layer will freely fall down and creep in this gap under gravity itself, resulting in casting surface wrinkling.
Chunliang Zhang and Liangchi Zhang
J. Huang et al., "An Investigation on Formation Mechanisms of Wrinkles on Steel Casting Surfaces", Key Engineering Materials, Vols. 531-532, pp. 295-298, 2013