Factor of safety

about FOS

1. Factor of Safety
◦Name of the Creator: NiteshKumar
◦Designation: AP
◦Department: Mechanical Engineering
◦School & University Name: School of
Engineering & Technology, Sharda
University

2. FACTOR OFSAFETY
•Itisdefinedastheratioofthematerialstrength
ultimatestrengthoryieldstrengthorendurance
strengthtotheworkingorallowablestress.
Factorofsafety=Materialstrength/Designstress
•Factorofsafetyforstaticloadingofductile
material:Incaseofthestaticloadingofductile
materialswheretheyieldpointisclearlydefined,the
factorofsafetyisbasedonyieldstrengthandisdefined
as
Factorofsafety=Yieldstrength/Designstress

3. •Factor of safety for static loading of brittle material: In case
of the static loading of material, the factor of safety is based
on the ultimatestrength.
Factor of safety= Ultimate strength/Designstress
•Factor of safety for fatigue loading: In case of fatigue
loading, the factor of safety is based on endurancelimit.
Factor of safety= Endurance limit/Designstress