Die Thermal Load & Life

Estimate die heat flux, temperature rise and thermal-fatigue cycles.

Die steel

Casting mass kg

Cavity surface area m²

Cycle time s

Latent heat kJ/kg

Cp J/kg·K

Pour temperature °C

Die temperature °C

Cooling water velocity m/s

Cooling channel dia. mm

Surface treatment

Phased thermal history

Result

Inverse S–N (allowable ΔT)

Target life (cycles) cycles

Note — Inverse S–N uses N₀·(ΔT₀/ΔT)^m to find the ΔT that meets a target life.

ΔT – life table — Calibrated to steel grade. Actual life varies with coating, cooling intensity and surface treatment.

ΔT (°C)	N (cycles)

Note — Color = log10(thermal-fatigue cycles). Greener = longer life. Crosshair = current working point.

Note — Calibrated to steel grade. Actual life varies with coating, cooling intensity and surface treatment.

Note — Surface treatment multiplies the empirical S–N life.

Note — Coffin–Manson is an elastic-strain screening bound; the empirical S–N stays conservative.

Note — Calibrated screening values; verify with die-maker / producer data.

Note — Die temperature auto-loaded from the selected alloy preset.

Note — Phased history accumulates damage by Miner's rule; the hottest phase carries no swing.