Inconel Hot Cracking Susceptibility Index
The Inconel hot cracking susceptibility index is a parameter that estimates the cracking tendency of nickel-based steel during welding. It helps in selecting suitable welding parameters.
Physicochemical mechanism of action
The Inconel hot cracking susceptibility index (IHA) measures the susceptibility of nickel-based steel to hot cracks during welding. This index takes into account low-melting grain boundary eutectics, which can lead to local stress areas at high temperatures.
Metallurgical relevance & welding risks
A high IHA indicates increased susceptibility to hot cracks. This can lead to incomplete weld seams, distortion, and low strength. Incorrect welding parameters can further increase the cracking tendency.
Workshop practice & instructions
To minimize the IHA, the following measures should be taken:
• Use suitable welding methods and parameters (e.g., MIG welding with low voltage).
• Keep the weld seam at a constant temperature to ensure uniform cooling.
• Avoid cooling rates that are too fast or too slow, as these can increase the cracking tendency.