Influence of Die Surface Texture on Tribological Performace for Tube Hydroforming

Tube hydroforming (THF) is an innovative method with a potential to form parts of various geometric complexities from tubular materials using pressurized fluid as a soft die. The process has numerous advantages over stamping: a) high strength to weight ratio, b) part consolidation, c) accuracy, d) improved stiffness, e) reduced scrap rate, and f) design flexibility. Optimal utilization of this method, particularly for hydoforming of complex parts, could be realized if better lubrication systems are devised. In an attempt to develop robust lubrication system for THF, the influence of textured die surfaces on tribological performance were studied through numerical modeling and experimentation. The pear shaped tooling developed by the author was used for evaluating the performance of hydroforming lubricants at the expansion zone. The effects of textured surfaces imprinted on the pear shaped dies were studied.