## Young's Modulus - Tensile Modulus or Modulus of Elasticity - for some common materials like steel, glass, wood ..

Tensile Modulus - Young's Modulus or Modulus of Elasticity - is a measure of stiffness of an elastic material. It is used to describe the elastic properties of objects like wires, rods or columns when they are stretched or compressed.

Tensile Modulus is defined as the

*"ratio of stress (force per unit area) along an axis to strain (ratio of deformation over initial length) along that axis"*

It can be used to predict the elongation or compression of an object as long as the stress is less than the yield strength of the material.

Material | Tensile Modulus (Young's Modulus, Modulus of Elasticity) - E - | Ultimate Tensile Strength - S_{u} -(10^{6} N/m^{2}, MPa) | Yield Strength - S_{y} -(10^{6} N/m^{2}, MPa) | |
---|---|---|---|---|

(10^{6 } psi) | (10^{9} N/m^{2}, GPa) | |||

ABS plastics | 1.4 - 3.1 | 40 | ||

Acetals | 2.8 | 65 | ||

Acrylic | 3.2 | 70 | ||

Aluminum Alloys | 10.2 | |||

Antimony | 11.3 | |||

Beryllium (Be) | 42 | 287 | ||

Beryllium Copper | 18.0 | |||

Bismuth | 4.6 | |||

Bone, compact | 18 | 170 (compression) | ||

Bone, spongy | 76 | |||

Boron | 3100 | |||

CAB | 0.8 | |||

Cadmium | 4.6 | |||

Carbon nanotube, single-walled | 1000+ | |||

Cast Iron 4.5% C, ASTM A-48 | 170 | |||

Cellulose, cotton, wood pulp and regenerated | 80 - 240 | |||

Cellulose acetate, molded | 12 - 58 | |||

Cellulose acetate, sheet | 30 - 52 | |||

Cellulose nitrate, celluloid | 50 | |||

Chlorinated polyether | 1.1 | 39 | ||

Chlorinated PVC (CPVC) | 2.9 | |||

Chromium | 36 | |||

Constantan | 162 | 455-860 | ||

Concrete | 17 | |||

Copper | 17 | 117 | 220 | 70 |

Diamond (C) | 1220 | |||

Douglas fir Wood | 13 | 50 (compression) | ||

Epoxy resins | 3-2 | 26 - 85 | ||

Fiberboard, Medium Density | 4 | |||

Flax fiber | 58 | |||

Glass | 50 - 90 | 50 (compression) | ||

Glass reinforced polyester matrix | 17 | |||

Gold | 10.8 | 74 | ||

Granite | 52 | |||

Graphene | 1000 | |||

Hemp fiber | 35 | |||

Inconel | 31 | |||

Iridium | 75 | |||

Iron | 28.5 | 210 | ||

Lead | 2.0 | |||

Magnesium metal (Mg) | 6.4 | 45 | ||

Manganese | 23 | |||

Marble | 15 | |||

MDF - Medium-density fiberboard | 4 | |||

Mercury | ||||

Molybdenum (Mo) | 40 | 329 | ||

Monel Metal | 26 | |||

Nickel Silver | 18.5 | |||

Nickel Steel | 29 | |||

Niobium (Columbium) | 15 | |||

Nylon-6 | 2 - 4 | 45 - 90 | 45 | |

Nylon-66 | 60 - 80 | |||

Oak Wood (along grain) | 11 | |||

Osmium (Os) | 80 | 550 | ||

Phenolic cast resins | 33 - 59 | |||

Phenol-formaldehyde molding compounds | 45 - 52 | |||

Pine Wood (along grain) | 9 | 40 | ||

Platinum | 21.3 | |||

Polyacrylonitrile, fibers | 200 | |||

Polybenzoxazole | 3.5 | |||

Polycarbonates | 2.6 | 52 - 62 | ||

Polyethylene HDPE (high density) | 0.8 | 15 | ||

Polyethylene Terephthalate, PET | 2 - 2.7 | 55 | ||

Polyamide | 2.5 | 85 | ||

Polyisoprene, hard rubber | 39 | |||

Polymethylmethacrylate (PMMA) | 2.4 - 3.4 | |||

Polyimide aromatics | 3.1 | 68 | ||

Polypropylene, PP | 1.5 - 2 | 28 - 36 | ||

Polystyrene, PS | 3 - 3.5 | 30 - 100 | ||

Polytehylene, LDPE (low density) | 0.11 - 0.45 | |||

Polytetrafluoroethylene (PTFE) | 0.4 | |||

Polyurethane cast liquid | 10 - 20 | |||

Polyurethane elastomer | 29 - 55 | |||

Polyvinylchloride (PVC) | 2.4 - 4.1 | |||

Potassium | ||||

Rhodium | 42 | |||

Rubber, small strain | 0.01 - 0.1 | |||

Sapphire | 435 | |||

Selenium | 8.4 | |||

Silicon Carbide | 450 | 3440 | ||

Silver | 10.5 | |||

Sodium | ||||

Steel, High Strength Alloy ASTM A-514 | 760 | 690 | ||

Tantalum | 27 | |||

Teflon. PTFE | 0.5 | |||

Thorium | 8.5 | |||

Tin | 47 | |||

Titanium | 16 | |||

Tungsten (W) | 400 - 410 | |||

Tungsten Carbide (WC) | 450 - 650 | |||

Vanadium | 19 | |||

Wrought Iron | 190 - 210 | |||

Zinc | 12 |

*1 N/m*^{2}= 1x10^{-6}N/mm^{2}= 1 Pa = 1.4504x10^{-4}psi*1 psi (lb/in*^{2}) = 144 psf (lb_{f}/ft^{2}) = 6,894.8 Pa (N/m^{2}) = 6.895x10^{-3}N/mm^{2}

### Strain

Strain is "deformation of a solid due to stress" - change in dimension divided by the original value of the dimension - and can be expressed as

ε= dL / L(1)

where

ε= strain(m/m) (in/in)

dL= elongation or compression (offset) of the object (m) (in)

L= length of the object (m) (in)

### Stress

Stress is force per unit area and can be expressed as

σ = F / A(2)

where

σ =stress(N/m^{2}) (lb/in^{2}, psi)

F= force (N) (lb)

A= area of object (m^{2}) (in^{2})

*tensile stress*- stress that tends to stretch or lengthen the material - acts normal to the stressed area*compressive stress*- stress that tends to compress or shorten the material - acts normal to the stressed area*shearing stress*- stress that tends to shear the material - acts in plane to the stressed area at right-angles to compressive or tensile stress

### Young's Modulus - Tensile Modulus, Modulus of Elasticity

Young's modulus can be expressed as

E = stress / strain

= (F / A) / (dL / L)(3)

where

E = Young's modulus (N/m^{2}) (lb/in^{2}, psi)

- named after the 18th-century English physician and physicist Thomas Young

### Elasticity

Elasticity is a property of an object or material which will restore it to its original shape after distortion.

A spring is an example of an elastic object - when stretched, it exerts a restoring force which tends to bring it back to its original length. This restoring force is in general proportional to the stretch described by Hooke's Law.

### Hooke's Law

One property of elasticity is that it takes about twice as much force to stretch a spring twice as far. That linear dependence of displacement upon stretching force is called Hooke's law which can be expressed as

F_{s}= -k dL(4)

where

F_{s}= force in the spring (N)

k= spring constant (N/m)

dL= elongation of the spring (m)

### Yield strength

Yield strength, or the yield point, is defined in engineering as the amount of stress that a material can undergo before moving from elastic deformation into plastic deformation.

### Ultimate Tensile Strength

The Ultimate Tensile Strength -* UTS *- of a material is the limit stress at which the material actually breaks, with sudden release of the stored elastic energy.