Moderate quality level C per ISO 5817
Moderate evaluation group C per ISO 5817 sets medium quality requirements for weld integrity for general industrial applications.
Physicochemical Mechanism of Action
Assessment group C defines a set of criteria that ensure the mechanical strength and toughness of the weld. These criteria cover hardness, stress state and the structure of the material.
Metallurgical Relevance & Welding Risks
With wrong handling, cracks or distortion can occur in the weld zone. Too high hardness can lead to cold or hot cracks if the material cools too fast. Cooling too slowly can lead to loss of toughness and grain coarsening.
Workshop Practice & Instructions
To meet the requirements of assessment group C, the welding material must have a hardness of 300 to 450 HB. The cooling times should be designed so that the time t8/5 lies between 10 and 20 seconds. This ensures sufficient toughness and prevents hot cracks.