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stress is the effect of applied force on the designed area of

part

Strength is a property of the material shows how it is

strong

Stress strength / f.o.s

To avoid failure in the designed part the max stress must

be less than the corresponding strength f.o.s 1

all = sofstrength

..

Allowable stress

Maximum stress

Design stress

Working stress

all = sofstrengthyield

..*2

.

(for ductile material)

Allowable shear stress

Maximum shear stress

Design shear stress

Working shear stress

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all = sofstrengthultimated

..

. (for brittle material)

Allowable shear stress

Maximum shear stress

Design shear stress

Working shear stress

Types of material

1-Ductile material

The designed strength is the yield strength

This material elongate more than 5% before fracture

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2- Brittle material

The designed strength is the ultimate strength Su

This material elongate less than 5% before fracture

stresses

1- normal sress 2- shear stress

i-tension/compression i-direct shear

ii-bending ii- torsional

iii-bearing iii- shear due to bending

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A A : Aluminium Assosiation

AGMA : American Gear Manufacturers Assosition

AISC : American Institute of steel Construction

AISI : American Iron and Steel Institute

ANSI : American National Standards Institute

ASME : American Society of Mechanical Engineers

ASTM : American Society of Testing and Materials

AWS : American Welding Society

ABMA : American Bearing Manufacturers Association

BSI : British Standards Institution

IFI : Industrial Fasteners Institute

SAE : Society of Automotive Engineers

ISO : International Standards Organization

NIST : National Institute for standards and Technologly

BIPM : International Bureau of weights and measures

I.MECH.E : Institution of Mechanical Engineers

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