AWS D17.2/D17.2M - Welding for Aerospace Applications: 2019

This specification covers requirements for resistance spot and seam welding of the following metals and their alloys.

Material Groups
Group 1: Aluminum and magnesium
Group 2: Steel, nickel, and cobalt
Group 3:Titanium

Classification. Classification is based on the following:
Class A: A welded joint, whose failure during any operating condition would cause loss of the equipment or system or one of its major components.
Class B: A welded joint whose failure would reduce the overall strength of the equipment or system or limit the intended functioning or use of equipment.
Class C: A welded joint for which no stress analysis is required and whose failure would not affect the performance of the equipment or system.