1. Physical properties Enrollment numbers 130610106041130610106042130610106043130610106044130610106045 Government engineering collage,Palanpur sub:- Applied mechanics

2. Group—C 01 Guidance By -- V.R.Sharma Guidance By -- V.R.Sharma

3. Strength -:- The capacity of material to withstand load is called “strength” -:- The strength of material is its ability to sustain loads without undue distortion,rupture,or collapse -:- A material have adequate strength in tension,compression,shear,bending or torsion -:- The max stress that any material can withstand is called ultimate strength

4. Elasticity External load applied on material than it undergoes deformation and remove load, it returns to original shape its called “elasticity” External load applied on material than it undergoes deformation and remove load, it returns to original shape its called “elasticity” Some material’s elasticity up to considerable range load Some material’s elasticity up to considerable range load Some materials elasticity low range of stress Some materials elasticity low range of stress Elastic properties importance to design engineer Elastic properties importance to design engineer

5. Plasticity Material does not regain its original shape, on removal load, it’s called “plastic limit” Material does not regain its original shape, on removal load, it’s called “plastic limit” Property of material by virtue of which material can be moulded in to desired shape Property of material by virtue of which material can be moulded in to desired shape It is lack of elasticity It is lack of elasticity

6. Ductility If material can undergo a considerable deformation, without rupture, it’s called “ductility” If material can undergo a considerable deformation, without rupture, it’s called “ductility” Ductile material undergo large deformation during tension test Ductile material undergo large deformation during tension test Ductile material suitable for tension member Ductile material suitable for tension member Steel,copper,wrought-iron,aluminium alloys and grey iron called ductile material Steel,copper,wrought-iron,aluminium alloys and grey iron called ductile material “Higher the percentage of elongation, more ductile is material” “Higher the percentage of elongation, more ductile is material” “Temperature increase,ductile increase” “Temperature increase,ductile increase” Metal having elongation, more 15% are ductile Metal having elongation, more 15% are ductile

7. Brittleness External forces act on material,than material can’t undergoes deformation or fails by rupture, it’s called “brittleness” External forces act on material,than material can’t undergoes deformation or fails by rupture, it’s called “brittleness” brittle material stronger in compression,weak in tension brittle material stronger in compression,weak in tension C.i.,glass,concrete,brick,china-ware etc is brittle materials C.i.,glass,concrete,brick,china-ware etc is brittle materials Compressive property of material Compressive property of material Material have less than 15% elongation consider as brittle Material have less than 15% elongation consider as brittle

8. malleability It is property of material by virtue of which material can be converted in to thin sheets by hammering it’s called ”malleability” It is property of material by virtue of which material can be converted in to thin sheets by hammering it’s called ”malleability” Can be easily rolled without cracking and breaking Can be easily rolled without cracking and breaking Gold,silver,copper,aluminium,tin,leadsteel are malleable material Gold,silver,copper,aluminium,tin,leadsteel are malleable material Gold – most malleable material Gold – most malleable material C.I. – least malleable material C.I. – least malleable material Also compressive quality of material Also compressive quality of material

9. Toughness Resistance to impact or shock loading is called “toughness” Resistance to impact or shock loading is called “toughness” it’s ability to withstand large stresses and strains without fracture it’s ability to withstand large stresses and strains without fracture Mild steel,wrought iron,manganese steel are good toughness property Mild steel,wrought iron,manganese steel are good toughness property Highly desirable quality in material for structural & machine parts subjected to shocks and vibration Highly desirable quality in material for structural & machine parts subjected to shocks and vibration

10. Hardness Resistance of a material to wear,abrasion,indenation, scratches is called “Hardness”. Resistance of a material to wear,abrasion,indenation, scratches is called “Hardness”. High resistance to indentation is desired in components like crank shaft,gears,axles etc. High resistance to indentation is desired in components like crank shaft,gears,axles etc. C.I.- hardest material C.I.- hardest material Magnesium - softest material Magnesium - softest material

11. Stiffness Resistance to deformation or strain is called “stiffness”. Resistance to deformation or strain is called “stiffness”. Stiffness of material measured by “modulus of elasticity (E). Stiffness of material measured by “modulus of elasticity (E). Higher value of E, more is stiffness. Higher value of E, more is stiffness. steel considered as stiffer material. steel considered as stiffer material.

12. Creep Increase in strain under sustained load called “creep” Increase in strain under sustained load called “creep” Low melting temperature like lead,tin,zinc may exhibits considerable creep at normal temperature Low melting temperature like lead,tin,zinc may exhibits considerable creep at normal temperature Creep phenomenon important for soft metals used at room temperature, steel cables, nuclear reactor Creep phenomenon important for soft metals used at room temperature, steel cables, nuclear reactor

13. Fatigue strength When a material is subjected to repeated loading,it is called ‘state of fatigue’ When a material is subjected to repeated loading,it is called ‘state of fatigue’ The maximum stress, which a material can withstand, under repeated stress cycles without fracture is called “ fatigue strength” The maximum stress, which a material can withstand, under repeated stress cycles without fracture is called “ fatigue strength” The capacity of material to withstand repeated stress cycle is known as Endurance of a material The capacity of material to withstand repeated stress cycle is known as Endurance of a material