An experimental test for measuring the friction between Ti-6Al-4V sheet material and S310 stainless steel tool material at 900degreesC is presented. The test is intended for application to Ti-6Al-4V superplastic forming for the manufacture of aeroengine components. The work is motivated by the need for accurate, representative data for process modelling, where accurate simulation is critical to formed component dimensions. The results show a time dependency of friction. The effects of boron nitride density, applied normal load and die surface roughness are investigated.