Mold Temperature Analysis Method of Hot Stamping Die Based on Actual Flow Field
Abstract
A mold temperature analysis method for the hot stamping dies of complex formed parts considering the influence of different flow field distribution is proposed. First, the convective heat transfer coefficients at each node of the cooling water pipe wall were calculated by Fluent flow field analysis, and the influence of the differences in the flow field distribution caused by the water channel structure on the heat transfer capacity was considered in this process. Then, the processes of sheet forming and holding and quenching were simulated by LS-DYNA to obtain the temperature data of the blank. Finally, the A-pillar side beam was used as the research object to compare the simulation analysis results with the actual cooling effect on the hot stamping production line. The results show that the distribution of high temperature areas in the analysis result of the mold temperature based on the flow field analysis is consistent with the actual measurement. The maximum error at the 12 temperature monitoring points is 3.6 ℃,and the average error is 0.96 ℃. However, the temperature distribution and the maximum temperature difference point change in the simulation using the average heat transfer coefficient. The maximum error of the monitoring point is 9.1 ℃,and the average error is 4.96 ℃.The comparison between the simulation and experiment shows that the change of the flow rate has a significant effect on the heat transfer coefficient, and the mold temperature analysis method based on flow field analysis takes into account the effect of the differential distribution of the flow rate in the cooling channel of the hot stamping mold,which can be used for the analysis of mold temperature of complex parts and multi-cavity molds.
Keywords: hot stamping, flow fields, convective heat transfer coefficients, cooling systems, temperature distribution
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ZHANGD J. Research on hot stamping high strength steel technology and forming die [J]. Internal Combustion Engine & Parts,2019 (19):71—73. (In Chinese)
LIU X F,JIA Z H,ZHANG Q,et al. Analysis on influencing factors of phase transformation inhomogeneity of synchronous quenching in hot stamping for ultra -high -strength steel plates [J]. Journal of Plasticity Engineering,2019,26 (2):245—252. (In Chinese)
HUANG C Q. Influence of die temperature on transition zone of hot stamping parts with variable strength for automotive B -pillar[J]. Forging and Stamping Technology,2019,44 (7):52—57. (In Chinese)
LIU D H,WAN Y X,ZHANG W J. Research on flow rate uniform optimization of hot stamping die cooling system [J]. Forging and Stamping Technology,2017,42 (12):104—108. (In Chinese)
LAI C G,MAN C,WEN K P,et al. Numerical study of cooling characteristics for blanking in hot stamping[J]. Hydromechatronics Engineering,2015,43 (6):27—31.
XIN Z Y,GAO N P,ZHU T. Numerical simulation investigation on cooling system of die in hot stamping process [J]. Hot Working Technology,2012,41 (1):170—174. (In Chinese)
XUE K M,SUN D Z,LI P,et al. Hot stamping forming process and experiments of 22MnB5 ultra-high strength steels [J]. China Mechanical Engineering,2017,28 (12):1498—1503. (In Chinese)
ZOU W,ZHANG L Q,ZAN Z W,et al. Simulation study on hot stamping process of ultra high strength steel [J]. Forging and Stamping Technology,2018,43 (8):75—79. (In Chinese)
ZHANG H,PAN A Q,LI S Y. Analysis and experimental study on process parameters of hot stamping of BR1500HS sheet metal[J]. Hot Working Technology,2019,48 (19):97—99. (In Chinese)
GUO Y H,MA M T,FANG G,et al. Numerical simulation of hot stamping of side impact beam [J]. Engineering Sciences,2012,10 (6):62—66.
ZHANG X Z,HUANG W,LIU Q G. Heat transfer[M]. Beijing:National Defense Industry Press,2011:89—95. (In Chinese)
WANG D S. Design specification of hot stamping forming die for the high strength steel plate [J]. China Metal Bulletin,2019 (4):105. (In Chinese)
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