Results of In-House Cone-Cup Testing of Low to High Temperature SPF-Alloys

摘要

Material testing of SPF-sheet is usually done with coupon hot tensile testing. The optimum range of strain rates is determined with stepped strain tests. To overcome the problem of very few available testing facilities and time consuming and costly procedure, cone cup testing has been developed since long. This test can be generated directly in the workshop, no machining of samples is necessary and it is very much related to the real SPF-process. The analysis of suitable temperature and strain rate is done by simple measurement of resulting cone height. This paper describes a unique and novel variant of the above mentioned baseline design. It provides on-line data of the actual status of the cone cup forming resulting from the applied, constant pressure. Strain rate variations as a result from texture or from the alloy-related behaviour is detectable. Thinning and "hardening" behaviour of different alloys up to maximum failure strain can be analysed in one sample. The test rig has been tested successfully with high temperature alloys like gamma Ti-aluminates down to low temperature SPF-alloys like Magnesium alloys. The acquired data pool is used for the optimisation of industrial SPF processes.