On the effect of testing setups on Aluminum alloys Interfacial Heat Transfer Coefficient Measurement

Sheet metal to die steel Interfacial Heat Transfer Coefficient (IHTC) is closely related to the cooling rate achieved in hot stamping. The need of ensuring a minimum cooling rate for a proper quenching of the hot stamped parts explains the research interest in determining the IHTC in dif-ferent scenarios. Several materials and process factors affect IHTC such as surface finish of the die and the sheet, their contact pressure and the temperature difference between them. Despite some laboratories have shown very similar results in back-to-back IHTC measurements, the lack of a standardized testing method still allows room for experimental deviations across some other laboratories. This work explores the differences found between two research groups when measur-ing the IHTC for 6111 aluminum alloy against QRO90 steel and outlines practical factors to be accounted for improving interpretation and use of the IHTC values found in literature.