Quality of gas metal arc welds for rapid prototyping and wear replacement

摘要

Rapid prototyping by Gas Metal Arc Welding is a method of making a prototype by creating layers of welds to form a desired shape. The work in this thesis investigates the feasibility of a robotic Gas Metal Arc Welding cell for rapid prototyping and wear replacement applications. The experiments were divided into two categories, ie. thin walled objects and solid objects. The optimal range of welding parameters for the two types of objects were investigated extensively for their suitability for rapid prototyping and wear replacement applications. The experiments include investigations of the mechanical property, surface temperature and surface regularity of the welded steel created by rapid prototyping and wear replacement techniques. The importance and the significance of selecting the correct welding parameters for rapid prototyping and wear replacement applications are demonstrated in this thesis. In the experiments, it was found that the welding parameters lie within a narrow range. It was also determined that the suitable settings are in the short-circuit transfer mode. However, in the case of the solid objects it was determined that spray transfer is a suitable transfer mode for the fill.