Abstract
Qualifying welding procedures for repair of components in high temperature service requires careful consideration of factors including identification of the materials involved, existing mechanical properties and service operating parameters such as temperature, pressure and environment. Selection of weld metals to match, under match or overmatch base material as well as direct and indirect consequences on the heat-affected zone also require evaluation. Application of post weld heat treatment and ramifications where dissimilar base materials are involved are discussed plus the necessity of conducting tests at the operating temperatures and conditions where information is not available from the literature. Each of these factors is discussed and examples provided.
