Material Properties Table

How it works

Choose the units, filter by group or search by name, and click a column heading to sort. Two columns are calculated for you: yield strength ÷ density (specific strength, how much load a unit of mass can carry) and modulus ÷ density (specific stiffness).

σ = E × ε

The values are typical room-temperature figures for common grades and tempers. Strength depends strongly on heat treatment, product form and temperature, and plastics also depend on moisture, print settings and loading rate, so use the supplier’s datasheet for design. The reasoning behind the numbers is on Materials and Their Properties; for sizes of a member see the Beam Calculator.

Worked example

Which is stiffer for its weight, steel or aluminum? Divide the modulus by the density: steel 200 GPa ÷ 7 850 kg/m³ = 25.5 MN·m/kg; aluminum 6061 69 GPa ÷ 2 700 = 25.5; titanium 114 ÷ 4 430 = 25.7. They are almost the same, which is why a lighter metal needs a bigger section (not a thinner one) to give the same stiffness. For strength the picture changes: 7075-T6 aluminum has a yield strength per density of 179 kN·m/kg against 32 for mild steel, so strength-limited parts do gain from lighter alloys.

Things to know

Plastic strength and stiffness change with temperature, moisture (nylon absorbs water and softens) and how the part was made (3D printed parts are weaker across the layers).

For plastics the last temperature column is the melting point for crystalline plastics (nylon, acetal, PEEK, PLA) and the glass transition for amorphous plastics (ABS, polycarbonate, acrylic, PETG), which is where they soften.

Aluminum and steel lose strength as they heat; aluminum loses about half its strength by 250 °C.

Thermal expansion matters for fits and joints between different materials: 100 mm of aluminum grows 0.24 mm for a 100 °C rise, steel 0.12 mm.

Common questions

Why is mild steel listed with a yield of 250 MPa?

That is the specified minimum for ASTM A36. Actual plate is often higher; use mill certificates for critical work.

What is the difference between yield and tensile strength?

Yield strength is the stress where permanent deformation starts, and tensile strength is the highest stress the material carries before it breaks. Design normally limits stress to a fraction of yield.

Are the values exact?

No. They are typical, rounded values. Grades, tempers and suppliers differ by several percent, plastics by much more.

Sources

• ASM Handbook, Volume 1 (properties and selection of irons, steels) and Volume 2 (nonferrous alloys); MatWeb material property data.
• ASTM A36, A240; ASTM B209 (aluminum sheet); manufacturer datasheets for polymers.

Last reviewed: November 2, 2026