TWI

Friction stir welding trials were undertaken on AA 7075-T7351 aluminium alloy plates (thickness 9.525 mm) to investigate the influence of backing plate characteristics on heat input and cooling rate. Experiments were performed on an MTI RM2 friction stir welder using a CS4 pin tool with an embedded thermocouple to facilitate determination of cooling rate on the advancing side HAZ of the weldment. The backing plate materials incorporated ceramic, marble, aluminium alloy, steel and granite materials with thermal conductivity ranging from 0.68-167 W/mK. Tool temperature, travel speed and backing plate were varied through a factorial experimental design. Statistical analyses were conducted to examine the relationships between process parameters (backing plate thermal conductivity, rotational speed, travel speed) on cooling rate and heat input.

10th International Symposium, 20-22 May 2014, Session 4A: Techniques I, Paper 04