Plasma-Assisted Sintering of Diffusion Bonded Dissimilar Titanium-SS304l: Role of Bonding Pressure and Heating Rate on Microstructure and Mechanical Properties.

In the present investigation, an effort has been made to join commercial pure titanium and stainless steel 304L by plasma-assisted heating techniques. The diffusion bonding is conducted at 750 °C with varying heating rates viz. 100, 150, 200, 250 °C/min with holding for 5 minutes with varying pressure condition (44 MPa). The bonding strength of the interfacial region is evaluated by the tensile test. The result shows that the diffusion of Fe in Ti leads to the formation and stabilization of Fe₂Ti in the interfacial zone. To understand the effect of varying holding time and heating rate, the bond width is studied using optical and scanning electron microscopes. It is observed that the thickness of the joint is reduced by increasing the heating rate. This leads to maximum bonding strength 418 MPa for the bond made at 150 °C/min withholding the pressure to room temperature whereas the bonding strength falls to 340 MPa at 200 °C/min due to the formation of a thick brittle intermetallic compound. [ABSTRACT FROM AUTHOR]