A new process of transformation superplastic bonding with interlayer and its joint microstructure

作者：Zhang, GF^*; Zhang, JX; Zhang, H; Pei, Y; Wang, SY

来源：Acta Metallurgica Sinica, 2003, 39(6): 655-660.

• transformation superplastic diffusion bonding
• interlayer
• low carbon steel

A new welding process of transformation superplastic diffusion bonding with interlayer (TSBI) is proposed, which is different from conventional transformation superplastic bonding (TSB) in the following: the TSBI process must be required to placed interlayer (such as amorphous foil) previously; the maximum temperature of thermal cycles must be higher than the liquidus of the interlayer and the transformation temperature of the base metal. The experiment of the new TSBI process is carried out to determine its merits and mechanisms using low carbon steel as base metal and Ni-base amorphous foil filler metal as interlayer. The process parameters are that the maximum temperature is 1050degreesC, the minimum temperature 400degreesC, the pressure 18 MPa and the number of temperature cycling 15. The evaluation on joints by using metallography and tensile testing shows that using TSBI process there is no remained voids at the interface, so the bonded ratio can be increased greatly and the number of temperature cycling decreased; the joint has high strongth and is not sensitive to the number of temperature cycling. The microstructure of bonded zone at room temperature is consisted of fine ferrite and a few Widmanstatten structures.

• 出版日期2003-6
• 单位西安交通大学