This standard defines degrees of weldability and brazeability for materials or families of materials used in the aerospace industry. It comprises a series of sheets, by materials or by material families, which: a) indicate the main titles, the typical chemical composition and the main characteristics; b) contain recommendations for welding and brazing; c) indicate a degree of weldability or brazeability for a given process under defined conditions; d) indicate a value of the mechanical strength coefficient of the welded joint for each welding process, when it could be extracted from bibliographic references referring to it. The joint coefficient is expressed as a ratio of the tensile strength of the welded joint to the tensile strength of the base alloy. To define preheating conditions, it recommends EN 1011-2 recommendations. These conditions depend on the calculation of carbon equivalent, welding energy per unit length, thickness, arc welding process and hydrogen rate in filler metal. It is applicable without restriction for the manufacturing of new parts or for repair.