Interlaboratory comparison for heat transfer coefficient identification in hot stamping of high strength steels

Abstract

The topic of the paper is the identification of the heat transfer coefficient (HTC) in hot stamping of boron steel sheets under conditions very close to the industrial ones. Two approaches followed by one lab in Germany and one lab in Italy are presented for HTC identification, showing the two experimental apparatuses that were set-up to conduct the tests, the procedures developed and applied to identify the HTC. The obtained results are compared in terms of dependence of HTC from the applied contact pressure, the similarities and the differences of the two approaches are outlined and commented.

Numerical simulation and optimization of hot stamping and quenching processes of automobile anticollision beam

“…2). High temperature characteristics of material should be considered, which means the coefficient of heat conduction, the specific heat and the thermal expansion coefficient of B1500HS are all variables [3]. The forming time is set as 0.2~1s.…”

Solution of boundary heat transfer coefficients between hot stamping die and cooling water based on FEM and optimization method

“…Bosetti et al [17] calculated the BHTC between the steel sheets and tools under conditions very close to the industrial ones. Abdulhay et al [18,19] designed an experimental device to accurately measure the thermal contact resistance under representative process conditions, and presented an approach to determine the evolution of the thermal contact resistance under different contact pressure .…”

Improving the Quality of Hot Stamping Parts with Innovative Press Technology and Inline Process Control

“…Weiss et al shows [6] that the heat transfer coefficient (HTC) between blank and die has a share of about 40% regarding the total thermal resistance a significant adjusting screw to shorten the quenching time. The dependency of the HTC was investigated through different testing procedures and institutions [7]. It is mainly affected by the temperature difference [8] and the contact pressure between the two contacting bodies [9].…”