Weld Heat Input Limit Tool
Check if your welding heat input is within typical acceptable ranges for different materials to prevent common welding defects and ensure desired mechanical properties.
Check Your Heat Input
Select the material and enter your calculated heat input (in kJ/mm).
The "Goldilocks" Principle of Heat Input
Heat input is a critical variable in welding. It's not just about melting the metal; it's about controlling the entire thermal cycle. Both too much and too little heat can be detrimental to the weld's final quality.
- Too Much Heat: Leads to a slow cooling rate, which can cause large, coarse grains to form in the Heat-Affected Zone (HAZ). This can significantly reduce the material's toughness and strength. It also increases distortion.
- Too Little Heat: Can cause a very fast cooling rate, which may lead to the formation of brittle structures like martensite, increasing the risk of cracking. It can also lead to defects like lack of fusion.
Every material has a "sweet spot" or an ideal range for heat input that produces the best combination of properties. This tool provides a general guide to these ranges for common material types.