%\text{\%}

percent strain

Strainexact by definition

Strain expressed as a percentage: 0.002 strain is 0.2%. Used where deformations are large enough for the ratio to be awkward — elongation at break for a ductile metal runs 20 to 40%, and for an elastomer several hundred.

Watch out: Percent elongation from a tensile test is measured over a stated GAUGE LENGTH and is not a material constant. The same steel reports different elongation on a 50 mm gauge than on a 200 mm one, because necking is local while the gauge length is not, so a figure quoted without its gauge length cannot be compared with another.

1 %\text{\%} 0.01 m/m\text{m/m}

One percent strain in every strain unit

0.01meter per meter (m/m)
0.01inch per inch (in/in)
10,000microstrain (µm/m)
10millimeter per meter (mm/m)
10mil per inch (mil/in)
1percent strain (%)this unit