TWI

A friction stir welding (FSW) methodology, incorporating Taguchi quality engineering to optimise process parameters, was developed to fabricate a cold plate consisting of copper pipe embedded in the machined groove of a 6061 aluminium alloy base plate, and the thermal performance of the welded specimens was investigated. Four types of FSW tools were employed, having a small straight pin, a medium straight pin, a medium tapered pin or a large tapered pin. Commercial copper pipe (diameter 10 mm, thickness 1 mm) was set into a base plate groove, covered with a 6061 aluminium alloy layer (thickness 3 mm), and the boundary between cover and base plate was welded. Experimental design was applied to optimise eight control factors: welding speed, pin position, plunge depth, cover width, pipe/pin distance, pipe thickness, tool rotational speed and welding direction. Thermal performance was characterised by determination of thermal resistance at two water flow rates and by analysis of signal/noise ratios for the measured parameters.

9th International Symposium, 15-17 May 2012, Session 11A: Applications III, Paper 03