What does AWS D1.1 require regarding the use of filler materials?

The requirement that filler materials must be compatible with base materials is a critical aspect of welding as outlined in AWS D1.1. This compatibility ensures that the welded joint achieves the desired mechanical properties and performance characteristics, such as strength and ductility. When filler materials are chosen that are compatible with the base metals, it allows for a sound weld that can resist various loads and stresses.

Utilizing compatible filler materials helps prevent defects such as cracking or poor fusion, which can compromise the integrity of the welded structure. This is especially important in structural applications where safety and durability are paramount. The AWS D1.1 code gives specific guidelines on the selection of filler materials based on the base materials used in the welding process, ensuring compliance with standards that govern the quality and reliability of welded connections.