Effects of Mold Temperature and Casting Temperature on Hot Cracking in Al-4.5 wt.% Cu Alloy

Abstract

Hot cracking is an important defect that occurs during solidification of aluminum-copper alloys. In this present work, the effects of mold temperature and casting temperature on hot cracking in the Al-4.5 wt.% Cu alloy has been studied using a ring mold for hot cracking assessment. For the experimental conditions, three mold temperatures between 150 and 350°C and three casting temperatures between 670 and 770°C were studied and Al-7 wt.% Si alloy was used as reference for comparison. The results showed Al-7 wt.% Si alloy has high resistance to hot cracking and no hot cracking forms under three different mold temperatures, while Al-4.5 wt.% Cu alloy shows significant hot cracking tendency under the same casting conditions. The severity of hot cracking in Al-4.5 wt.% Cu alloy decreased significantly with increasing the mold temperature and decreasing the casting temperature. On the other hand, an increasing casting temperature resulted in severer hot cracking in Al-4.5 wt.% Cu alloy.

Archives of Foundry Engineering

“…Meanwhile, the temperature of 737°C (superheat temperature of 124°C) was provided to the Al-7wt.%Si alloy. The results showed that hot tearing significantly reduced with decreasing pouring temperature [21]. Another previous study also showed that the effect of three different pouring temperatures (700, 750, and 800°C) was predicted for A356 and M206 alloys on hot tearing susceptibility.…”

“…( 21). (21) This indicated that a crack was formed when the HCS was greater than one, showing that the model was used to qualitatively and quantitatively predict hot tearing. In this calculation, εθθ was obtained from the FEM simulation, with εfr being 0,0018 [96].…”

“…The hot tearing susceptibility category of the bycatch value was determined as follows [21,42]: < 0.5 = no hot tearing susceptibility, 0,5 -1.25 = small tearing susceptibility, 1.25 -2.25 = moderate tearing susceptibility, 2.25 -3.5 = high hot tearing susceptibility, > 3.5 = very high hot tearing susceptibility.…”