Exact and approximate methods for determining the thermal parameters of the forging process

Numerical simulation of the forged body plastic flow is a very important and indispensable technique in the mechanical forming. The correct simulation of changing the shape of a hot blank requires the use of very accurately determined physical parameters. There is thus a pressing need to create and supplement a database containing the exact physical parameters of forged materials. The following paper shows the results of development of methods to determine two thermal parameters of a solid body: the average value of the total emissivity and the average coefficient of heat transfer by convection. The methods of determining thermal parameters, described below, are considerably simpler than traditional ones, and they do not require the use of complicated equipment. The exact method is based only on processing of experimental data. In the approximate method, both the experimental data and theoretical values of thermal parameters available in the literature are used. The developed methods were applied to determine thermal parameters of test bodies of SAE 1045 steel and ABNT 6061 aluminum alloy.