DIFFUSION BONDING SUPERPLASTIC FORMING OF TI-6AL-6V-2SN SUS 304-STAINLESS-STEEL TI-6AL-6V-2SN/

The superplasticity of the Ti-6Al-6V-2Sn alloy for different temperatu res was evaluated by single-sheet free blowing. The optimal superplast ic temperature for the Ti-6Al-6V-2Sn alloy was found to be 850 degrees C. Diffusion bonding of Ti-6Al-6V-2Sn and 304 stainless steel was car ried out in a vacuum. The interface of both bonded alloys was examined by EPMA. The concentration profile of Ni exhibited a peak at the inte rlayer and a valley adjacent it, whereas that of Cr exhibited a peak w here Ni showed the valley. X-ray diffraction (XRD) analyses showed tha t the Fe2Ti, NiTi, and CrMn intermetallic compounds and the Cr element formed at the interface. The thickness profiles of the blown specimen s were measured and compared with theoretical calculations.