Quality level D according to ISO 5817
Evaluation group D per ISO 5817 says that weld quality is acceptable for light mechanical loads. It doesn't require super high standards.
Physical-Chemical Working Mechanism
Evaluation group D per ISO 5817 deals with the quality and hardness of the weld. It considers the chemical interaction of the metals and the microstructure that develops during welding.
Metallurgical Relevance & Risks When Welding
This group is for parts that aren't under high mechanical loads. But too high hardness or a bad weld can still cause cracks and failure. The weld must be stable and free of visible defects.
Workshop Practice & Operating Instructions
For parts in evaluation group D:
• Use proper welding methods like TIG or MIG welding.
• Make sure the weld is stable and has no pores or cracks.
• Check the microstructure with a microscope if needed.
• Keep the weld hardness in the range of 300 to 450 HB.