Development of a Low Cost Process for Manufacturing of Ti-MMC by Roll-Diffusion-Bonding

Abstract

Titanium-alloy matrix composites (TMC) are nowadays one of the material class with the highest specific resistance from room temperature up to 800° C. Centro Sviluppo Materiali SpA (CSM) efforts have been focused on the developing of an innovative solution to reduce the process costs. The new approach consists in an experimental “diffusion bonding” plant for co-rolling at high temperature sheets of titanium alloy and silicon carbide monofilaments fabrics. The result is a process cost reduction of about 40% respect to HIP process. The experimental pilot plant has been proposed for patent with n° 2006A000261 on may 2006. This paper describes the pilot plant and the process results. The metallographic examination on products shows full bonded samples (100 mm wide and 1500 mm long) obtained in a work field that is at least 100 times faster than that of HIP. High temperature tensile tests have been carried on Roll Diffusion Bonded specimens and the results are reported in comparison with those obtained by Isostatic Pressing (HIP) and Thermal- Spraying (TS) processes on the same composite.