Forecast on Upsetting Crack Based on Numerical Simulation

Abstract:

To improve the forging quality and avoid longitudinal cracks on forging surface, critical hole expansion ratio of ductile failure of metallic materials micromechanics was adopted as the criterion to judge whether crack occurs during upsetting, and the upsetting FEA model of 5CrNiMo hot die steel was established based on FEM software DEFORM-3D. The dangerous points on forging surface which crack may occur easily were analyzed based on the calculating results of the metal hole expansion ratio, and the influence of forgings shape on upsetting cracks were researched. The results show that when the relative reduction of the center point on the forgings surface exceeds 65%, the first crack occurs during upsetting; the shape coefficient can be used as the conditions and basis for cracks forecast by establishing the comparison expression between shape coefficient and hole expansion ratio during upsetting.

• Periodical: Advanced Materials Research (Volume 852)
• Pages: 561-566
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.852.561
• Online since: January 2014
• Authors: Yan Bo Fan, Qin Xiang Xia, Ming Ke Lv, Xue Zhi Zhao, Yu Lian Du
• Keywords: Forging Surface Longitudinal Cracks, Hole Expansion Ratio, Hot Die Steel, Numerical Simulation, Upsetting

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