HAZ Width Calculator

Estimate heat affected zone width using thermal analysis based on the Rosenthal equation.

Calculate using Heat Input Calculator if needed

2D for thick plates, 3D for thin sheets

A1 transformation temp for steel (~723C), recrystallization for Al

Material Thermal Properties

Material k (W/m-K) Cp (J/kg-K) Tm (C)
Carbon Steel504801500
Stainless 304165001450
Aluminum 6061167896650
Titanium Gr2175201670
Inconel 625104101350

Understanding the Heat Affected Zone

HAZ Formation

  • Definition: Region of base metal that experiences thermal cycles affecting microstructure but does not melt
  • Temperature Range: From melting temperature down to transformation/recrystallization temperature
  • Key Factor: Heat input - higher heat input = wider HAZ

HAZ Zones in Steel

  • CGHAZ (Coarse Grain): Near fusion line, >1100C, large austenite grains
  • FGHAZ (Fine Grain): 900-1100C, normalized structure
  • ICHAZ (Intercritical): A1-A3 range (723-850C), partial transformation
  • SCHAZ (Subcritical): Below A1, tempered or stress relieved

Rosenthal Equation (2D)

For thick plates with 2D heat flow:

T - T0 = (q / 2*pi*k*t) * exp(-v*r / 2*alpha) * K0(v*r / 2*alpha)

Where: q = heat input, k = conductivity, t = thickness, v = travel speed, alpha = thermal diffusivity, K0 = Bessel function