Metals Database
Steels, stainless and non-ferrous alloys with density and the property classes each is normally supplied in.
Overviewwhat this group covers and how to read the numbers
Metal is the default choice for a fastener, and the decision usually comes down to two things: how much load the joint carries, and what the joint will be exposed to. A property class answers the first; the alloy family answers the second.
Density is what turns a drawing into a weight, and it is remarkably uniform across the steels — carbon, alloy and stainless all sit within a few percent of each other. Switching from steel to aluminium is what moves the number, cutting it to roughly a third.
The property class figures alongside each material describe heat-treated alloy steels. They have no meaning for brass, aluminium or titanium in this list, which are supplied against their own designations rather than a tensile class.
Entries come in two kinds, and the difference matters when you read the numbers. A family entry — carbon steel, alloy steel, aluminium — covers a group and is bought against a tensile class or a supplier designation; no single set of mechanical figures describes it. A named grade entry — 304, 316, A36, 1018, 6061-T6, 6063-T5 — is one alloy in one condition, and carries its yield strength, tensile strength, stiffness and hardness.
Grade figures are labelled by basis, because two different things are being quoted. Some are minimums the standard guarantees, which is what a design calculation uses; others are typical published values, which is what a data sheet lists. The page says which, and names the source, every time.
steel4 entries
stainless2 entries
non-ferrous5 entries
Density comparisonevery metals entry on one scale
Weight calculator| Material | Group | Density (g/cm³) | kg/m³ |
|---|---|---|---|
| Aluminium | non-ferrous | 2.7 | 2700 |
| Aluminium 6061-T6 | non-ferrous | 2.7 | 2700 |
| Aluminium 6063-T5 | non-ferrous | 2.7 | 2700 |
| Titanium | non-ferrous | 4.51 | 4510 |
| Carbon Steel | steel | 7.85 | 7850 |
| Alloy Steel | steel | 7.85 | 7850 |
| Carbon Steel A36 | steel | 7.85 | 7850 |
| Carbon Steel 1018 | steel | 7.87 | 7870 |
| Stainless Steel A2 (304) | stainless | 7.9 | 7900 |
| Stainless Steel A4 (316) | stainless | 8 | 8000 |
| Brass | non-ferrous | 8.5 | 8500 |
Densest entry: Brass at 8.5 g/cm³. Lightest: Aluminium at 2.7 g/cm³.
Common applicationswhere these materials are actually used
Built from these materialsprojects whose bill of materials calls for a metals material
All projectsFrequently asked questionsabout metals selection
Which metal should I choose for outdoor use?
Stainless A4 (316) where chlorides are present — coastal air, salt water, swimming pools — because the molybdenum addition resists pitting that A2 will not. Inland, A2 (304) is normally sufficient and costs less. Plain carbon steel needs a coating and even then will not match either.
Why is aluminium not always the lightest option for a fastener?
Its density is about a third of steel, but its permissible load is far lower, so a joint of the same strength needs a larger aluminium fastener — which eats much of the weight saving. It also corrodes galvanically against steel, so the two should not be mixed without insulation.
What is the lightest metal in this database?
The density comparison above ranks every metal in this list and names the lightest and heaviest, so the answer stays correct as entries are added.
Do all these metals use the same property classes?
No. The numbered classes such as 8.8 and 10.9 describe quenched and tempered steel bolts to ISO 898-1. Stainless uses its own designations (A2-70, A4-80) and non-ferrous metals such as brass and aluminium are supplied against material designations instead.