Analysis on Void Closure Behavior during Hot Open Die Forging
Internal voids have to be eliminated for defect-free in some open die forging. The FEM analysis is performed to investigate the overlap defect of cast ingots during cogging stage. The measured flow stress data were used to simulate the cogging process of cast ingot using the practical material properties. Also the numerical analysis of void closure is performed by using the DEFORMTM-3D. The calculated results of void closure behavior are compared with the measured results before and after upsetting, which are scanned by the X-ray scanner. From this result, the criteria for deformation amounts effect on the void closure were estimated into effective strain of 0.6 by the comparison of practical experiment and numerical analysis.
Young Won Chang, Nack J. Kim and Chong Soo Lee
Y. S. Lee et al., "Analysis on Void Closure Behavior during Hot Open Die Forging", Advanced Materials Research, Vols. 26-28, pp. 69-72, 2007