Tensile strength

**Tensile strength** is a measurement of the force required to pull something such as rope, wire, or a structural beam to the point where it breaks.

The tensile strength of a material is the maximum amount of tensile stress that it can take before failure, for example breaking.

There are three typical definitions of tensile strength:

- Yield strength - The stress a material can withstand without permanent deformation. This is not a sharply defined point. Yield strength is the stress which will cause a permanent deformation of 0.2% of the original dimension.

- Ultimate strength - The maximum stress a material can withstand.

- Breaking strength - The stress coordinate on the stress-strain curve at the point of rupture.

## Typical tensile strengths

Some typical tensile strengths of some materials:
|Material|Yield strength (MPa) !! data-sort-type="number" | Ultimate strength (MPa) !! data-sort-type="number" | Density (g/cm³)|||
| --- | --- | --- | --- |
|Structural steel ASTM A36 steel|250|400|7.8|
|Steel, API 5L X65 (Fikret Mert Veral)|448|531|7.8|
|Steel, high strength alloy ASTM A514|690|760|7.8|
|Maraging_Steel, Grade 350|2400|2500|8.1|
|Steel Wire|||7.8|
|Steel, Piano wire|c. 2000||7.8|
|High density polyethylene (HDPE)|26-33|37|0.95|
|Polypropylene|12-43|19.7-80|0.91|
|Stainless steel AISI 302 - Cold-rolled|520|860|8.03;|
|Cast iron 4.5% C, ASTM A-48|130 (??)|200|7.3;|
|Titanium Alloy (6% Al, 4% V)|830|900|4.51|
|Aluminum Alloy 2014-T6|400|455|2.7|
|Copper 99.9% Cu|70|220|8.92|
|Cupronickel 10% Ni, 1.6% Fe, 1% Mn, balance Cu|130|350|8.94|
|Brass||250||
|Tungsten||1510|19.25|
|Glass (St Gobain "R")|4400 (3600 in composite)||2.53|
|Bamboo|142|265|.4|
|Marble|N/A|15||
|Concrete|N/A|3||
|Carbon Fiber|N/A|5650|1.75|
|Spider silk|1150 (??)|1200||
|Silkworm silk|500|||
|Kevlar|3620||1.44|
|Vectran||2850-3340||
|Pine Wood (parallel to grain)||40||
|Bone (limb)||130||
|Nylon, type 6/6|45|75|1.15|
|Rubber|-|15||
|Boron|N/A|3100|2.46|
|Silicon, monocrystalline (m-Si)|N/A|7000|2.33|
|Sapphire (Al<sub>2</sub>O<sub>3</sub>)|N/A|1900|3.9-4.1|
|Carbon nanotube (see note below)|N/A|62000|1.34|

- Note: Multiwalled carbon nanotubes have the highest tensile strength of any material yet measured, with labs producing them at a tensile strength of 63 GPa, still well below their theoretical limit of 300 GPa.  However, as of 2004, no macroscopic object constructed of carbon nanotubes has had a tensile strength remotely approaching this figure, or substantially exceeding that of high-strength materials like Kevlar.

- Note: many of the values depend on manufacturing process and purity/composition.

|Elements in the annealed state|Young's Modulus (GPa) !! Proof or yield stress (MPa) !! Ultimate strength (MPa)|||
| --- | --- | --- | --- |
|Aluminium|70|15-20|40-50|
|Copper|130|33|210|
|Gold|79||100|
|Iron|211|80-100|350|
|Lead|16||12|
|Nickel|170|14-35|140-195|
|Silicon|107|5000-9000||
|Silver|83||170|
|Tantalum|186|180|200|
|Tin|47|9-14|15-200|
|Titanium|120|100-225|240-370|
|Tungsten|411|550|550-620|
|Zinc (wrought)|105||110-200|
(Source: A.M. Howatson, P.G. Lund and J.D. Todd, "Engineering Tables and Data" p41)

## Related pages

- Tension (mechanics)
- Tensile stress
- Deformation

## Other websites

- January 2003 sci.physics thread on water tensile strength and trees
- Theory re the discrepancy in static vs dynamic measurements of water's tensile strength