Rapid prototyping based on variable polarity gas tungsten arc welding for a 5356 aluminium alloy

This paper presents a new deposition process for directly building cylindrical parts of the 5356 aluminium alloy with variable polarity gas tungsten arc welding (VPGTAW). The relationship between the geometric sizes of the deposited layer and the welding parameters is investigated. A machine vision sensor is used to monitor and control the arc length that is a key welding parameter in the achievement of a uniform deposition. By optimizing the depositing speed and the thickness of the depositing layer, there is no need for a cooling system to cool the part. Three-dimensional parts with diVerent wall thicknesses and diVerent shapes are successfully obtained. The surfaces of the deposited parts are smooth and uniform.