This article describes the weldability tests that are used to evaluate the effects of welding on such properties and characteristics as base-metal and weld-metal cracking; base-metal and weld-metal ductility; weld penetration; and weld pool shape and fluid flow. It also describes several weldability tests for evaluating cracking susceptibility, classified as self-restraint or externally loaded tests. The article discusses the processes, advantages, and disadvantages of the weld pool shape tests, the weld penetration tests, and the Gleeble test.

This article reviews weldability of aluminum alloys and factors that affect weld performance. It first addresses hot tears, which can form during the welding of various aluminum alloys. It then presents comparison data from different weldability tests and discusses the specific properties that affect welding, namely oxide characteristics; the solubility of hydrogen in molten aluminum; and its thermal, electrical, and nonmagnetic characteristics. The article addresses the primary factors commonly considered when selecting a welding filler alloy, namely ease of welding or freedom from cracking, tensile or shear strength of the weld, weld ductility, service temperature, corrosion resistance, and color match between the weld and base alloy after anodizing. A number of factors, both global and local, that influence the fatigue performance of welded aluminum joints are also covered.