TWI Industrial Member Report Summary 386/1988
I D Harris
Scope
This review includes recent experimental evidence and present information on the causes, formation, and avoidance of porosity when MIG welding a range of materials including carbon and low alloy steels, austenitic stainless steels, aluminium and its alloys, copper and its alloys, and nickel and its alloys.
The classification and appearance of the various types of porosity are described, with reference to relevant standards. Methods of assessing gas shielding efficiency are also described.
The effect of porosity on mechanical properties is outlined, and comparisons are drawn with the effects of other types of defects.