inductionheatingguide.com

Engineering tools for
induction heating

Frequency selection, power sizing, skin depth, Curie temperature, and material conductivity — calculated from physics, not guesswork.

Skin Depth Formula
δ = √( ρ / π·f·μ₀·μᵣ )
δskin depth (mm) — drives frequency choice
ρelectrical resistivity of material (Ω·m)
ffrequency (Hz) — your control variable
μ₀permeability of free space (4π × 10²&sup7;)
μᵣrelative permeability — 200 for steel, 1 for Al
118
Elements covered
40+
Specific alloys
7
Interactive calculators
5
Reference tools
01

Select material

Choose from 10 categories and 40+ specific alloys. Resistivity, permeability, Cp, density, and Curie temperature auto-populate.

02

Set objective

Surface hardening, brazing, annealing, melting, wire annealing — target temperature auto-fills from material + process.

03

Enter geometry

Shaft, tube, plate, gear, billet, wire. Enter the key dimension — wall thickness, coil length, line speed for wire mode.

04

Get results

Frequency range, skin depth, power per part, recommended supply kW — with Curie and safety alerts.

Physics

Skin Depth & Frequency

Why δ = √(ρ/πfμ₀μᵣ) is the central equation in induction heating — and how material properties and geometry both drive your frequency choice.

Magnetics

Curie Temperature

How ferromagnetic materials lose permeability at the Curie point — and what the "Curie knee" means for your power supply and heating curve.

Power

Supply Sizing

P = m·Cp·ΔT / (t·η) — how mass, heat time, coil efficiency and radiation losses combine to determine the kW rating you need.

Coil Design

Coil Geometry

Solenoid, pancake, hairpin, split-return — how coil type and coupling gap affect efficiency, temperature uniformity and power factor.

Materials

Non-Magnetic Materials

Why aluminum, copper and titanium require higher frequency and more power — and how to compensate with coil geometry and coupling distance.

Process

Continuous Wire

Dwell time, mass per metre, throughput — how line speed, coil length and wire diameter interact in continuous induction annealing.

Geometry

Tube & Pipe Heating

Wall thickness — not OD — drives frequency selection. How to avoid opposite-wall heating in thin-walled tubes.

Indirect

Susceptor Heating

Why powder, scraps and ceramics can't be directly induction heated — and how a conductive graphite or metal susceptor solves it.

Hardening

Surface vs Through Hardening

How case depth, frequency and dwell time interact — and why surface hardening needs frequency an order of magnitude higher than through hardening.