Warm and hot blanking processes were developed for solving problems in piercing and trimming of press-hardened parts, some fine blank parts with comprehensive mechanical properties could be produced by hot blanking. To establish the optimum blanking processes and evaluate the effect of blanking temperature on the sheared section surface and fracture direction. Along with the fracture mechanism and microstructure of the parts, a series of hot blanking experiments for B1500HS steels were carried out at different blanking temperatures (450–800°C) and an 8% die clearance. The experimental results show that with the blanking temperature, the smooth (burnish) zone width increases, and the fracture direction becomes nearly normal. The sheared section surface of the parts mainly demonstrates ductile fracture mainly, accompanied by local brittle fracture over the blanking temperature range of 450–600°C. A ductile fracture region contains a great amount of fine equiaxed dimples over the blanking temperature range of 650–800°C, their microstructure is of complete martensite.
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References
P. F. Bariani, S. Bruschi, A. Ghiotti, and A. Turetta, “Testing formability in the hot stamping of HSS,” CIRP Ann. - Manuf. Techn., 57, No. 1, 265–268 (2008).
J. Cui, C. Lei, Z. Xing, et al., “Predictions of the mechanical properties and microstructure evolution of high strength steel in hot stamping,” J. Mater. Eng. Perform., 21, No. 11, 2244–2254 (2012).
H. Li, L. He, G. Zhao, and L. Zhang, “Constitutive relationships of hot stamping boron steel B1500HS based on the modified Arrhenius and Johnson–Cook model,” Mater. Sci. Eng. A, 580, 330–348 (2013).
H. S. Choi, B. M. Kim, D. H. Kim, and D. C. Ko, “Application of mechanical trimming to hot stamped 22MnB5 parts for energy saving,” Int. J. Precis. Eng. Man., 15, No. 6, 1087–1093 (2014).
H. S. Liu and C. X. Lei, “Local heating-aided hot blanking of quenched ultra high strength steel BR1500HS,” Int. J. Adv. Manuf. Tech., 77, Nos. 1–4, 629–641 (2014).
K. Mori, T. Maeno, and S. Fuzisaka, “Punching of ultra-high strength steel sheets using local resistance heating of shearing zone,” J. Mater. Process. Tech., 212, No. 2, 534–540 (2012).
K. Mori, S. Saito, and S. Maki, “Warm and hot punching of ultra high strength steel sheet,” CIRP Ann. - Manuf. Techn., 57, No. 1, 321–324 (2008).
H. So, D. Faßmann, H. Hoffmann, et al., “An investigation of the blanking process of the quenchable boron alloyed steel 22MnB5 before and after hot stamping process,” J. Mater. Process. Tech., 212, No. 2, 437–449 (2012).
M. Nikravesh, M. Naderi, G. H. Akbari, and W. Bleck, “Phase transformations in a simulated hot stamping process of the boron bearing steel,” Mater. Design, 84, 18–24 (2015).
J. Min, J. Lin, and Y. Min, “Effect of thermo-mechanical process on the microstructure and secondary-deformation behavior of 22MnB5 steels,” J. Mater. Process. Tech., 213, No. 6, 818–825 (2013).
N. Bonora, D. Gentile, A. Pirondi, and G. Newaz, “Ductile damage evolution under triaxial state of stress: Theory and experiments,” Int. J. Plasticity, 21, No. 5, 981–1007 (2005).
A. Sancho, M. J. Cox, T. Cartwright, et al., “Experimental techniques for ductile damage characterisation,” Proc. Struct. Integr., 2, 966–973 (2016).
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This work was financially supported by the National Natural Science Foundation of China (51575324, 51175302), and the Science and Technology Development Program of Shandong (2014GGX103024).
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Translated from Problemy Prochnosti, No. 1, pp. 161 – 166, January – February, 2018.
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Hou, H.L., Li, H.P. & He, L.F. Fracture Characteristics of B1500HS Steel Hot Blank Parts. Strength Mater 50, 146–150 (2018). https://doi.org/10.1007/s11223-018-9953-1
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DOI: https://doi.org/10.1007/s11223-018-9953-1