What is thermal conductivity?

Thermal conductivity (k) is a material property that describes how readily heat flows through it. A high k (e.g., copper at ~400 W/m·K) means the material conducts heat easily; a low k (e.g., aerogel at ~0.015 W/m·K) means it is a good insulator.

What is Fourier's law?

Fourier's law states that the heat flux through a material is q = k × (ΔT / L), where ΔT is the temperature difference across the slab and L is its thickness. Total heat flow is Q = q × A, where A is the cross-sectional area.

Are these values exact?

The values are typical room-temperature references. Thermal conductivity varies with temperature, purity, alloy composition, and manufacturing process. For critical design work, always verify against manufacturer datasheets or standards such as ASTM E1952.

Why are metals much more conductive than polymers?

Heat conduction in metals is dominated by free electrons, which transfer energy very efficiently. Polymers and ceramics rely on slower phonon (lattice vibration) conduction, resulting in conductivity values one to four orders of magnitude lower than metals.

Can I use this for composite or laminated walls?

This calculator handles a single homogeneous layer. For multilayer walls, calculate each layer's thermal resistance R = L/(k×A) separately and sum them: Q = ΔT_total / R_total.

Thermal Conductivity Material Reference

Name: Thermal Conductivity Material Reference
Availability: InStock
Author: Nham Vu

Look up thermal conductivity (W/m·K) for 40+ materials and calculate steady-state heat flow through a slab using Fourier's law.

Material Thermal Conductivity Reference

Material	Category	k (W/m·K)	Use

Values are typical at ~25 °C. Click a row to load its k value into the calculator.

Fourier Heat-Flow Calculator

Steady-state conduction through a flat slab: q = k · (ΔT / L)

Thermal Conductivity k (W/m·K)

W/m·K

Wall / Slab Thickness L

Cross-sectional Area A

Hot-side Temp T₁

Cold-side Temp T₂

Summary

Look up thermal conductivity (W/m·K) for 40+ materials and calculate steady-state heat flow through a slab using Fourier's law.

How it works

Type a material name in the search box to filter the reference table instantly.
Click any row to pre-fill the material's k value into the Fourier's law calculator.
Enter wall thickness, area, and the hot- and cold-side temperatures in the calculator.
Click Calculate to see heat flux (W/m²) and total heat flow (W) for the slab.
Use the category filter buttons to browse metals, polymers, insulation, and more.

Use cases

Selecting insulation materials for walls, roofs, or pipes.
Comparing metals for heat sink or heat exchanger design.
Estimating heat loss through a building element or furnace wall.
Quick look-up during thermal analysis or FEA preprocessing.
Teaching or studying heat transfer fundamentals.
Cross-checking material data in engineering datasheets.

Frequently Asked Questions

Last updated: 2026-07-01 · Reviewed by Nham Vu