MECHANICAL PROPERTIES

• PROPERTIES


  CHARACTERISTICS ATTRIBUTED TO THE METAL'S COMPOSITION
• MECHANICAL BEHAVIOR


  REFLECTS THE RELATIONSHIP BETWEEN ITS RESPONSE OR DEFORMATION TO AN APPLIED FORCE/LOAD.
• FORCE


  AMOUNT OF PUSHING AND PULLING REQUIRED TO MOVE AN OBJECT
• TENSION


  TWO PULLING (OPPOSING) FORCES THAT STRETCH AN OBJECT TRYING TO PULL IT APART.
• COMPRESSION


  TWO PUSHING (OPPOSING) FORCES THAT SQUEEZE AN OBJECT TRYING TO COMPRESS IT.
• SHEAR


  TWO PUSHING OR PULLING ADJACENT FORCES, ACTING CLOSE TOGETHER BUT NOT DIRECTLY OPPOSING EACH OTHER.
• TORSION


  CREATED WHEN A MOMENT OR TURNING FORCE IS APPLIED TO A STRUCTURAL MEMBER (OR PIECE OF A MATERIAL) MAKING IT DEFLECT AT AN ANGLE TWIST.
• TWISTING/TORSIONAL MOMENT


  A MOMENT THAT CAUSES TWISTING
• TORSION


  PRODUCES SHEAR STRESSES INSIDE THE MATERIAL
• STRESS-STRAIN TEST


  IF A LOAD IS STATIC OR CHANGES RELATIVELY SLOWLY WITH TIME AND IS APPLIED UNIFORMLY OVER A CROSS SECTION OR SURFACE OF A MEMBER, THE MECHANICAL BEHAVIOR IS KNOWN BY APPLYING THIS.
• TENSION TEST


  A SPECIMEN IS DEFORMED, USUALLY TO FRACTURE, WITH A GRADUALLY INCREASING TENSILE LOAD THAT IS APPLIED UNIAXIALLY ALONG THE LONG AXIS OF A SPECIMEN.
• DOGBONE SPECIMEN CONFIGURATION


  CHOSEN SO THAT DURING TESTING, DEFORMATION IS CONFINED TO THE NARROW CENTER REGION (WHICH HAS A UNIFORM CROSS SECTION ALONG ITS LENGTH).
• 12.8 MM


  STANDARD DIAMETER IN TENSION TEST
• REDUCED SECTION LENGTH IN TENSION TEST.

  60 MM (4X THE DIAMETER)
• 1 MPA = N/M^2

  10^6
• 1 MPA = PSI

  145
• WHERE IS COMPRESSIVE STRESS USUALLY SEEN?

  X-AXIS
• WHAT DOES INSTANTANEOUS MEAN IN MSE? (E.G. INSTANTANEOUS LENGTH)

  FINAL
• VALUE OF STRAIN IS (BLANK) OF THE UNIT SYSTEM.

  INDEPENDENT
• COMPRESSION TEST


  USED WHEN A MATERIAL'S BEHAVIOR UNDER LARGE AND PERMANENT STRAIN IS DESIRED, AS IN MANUFACTURING APPLICATIONS, OR WHEN THE MATERIAL IS BRITTLE IN TENSION.
• TORSION


  VARIATION OF PURE SHEAR WHEREIN A STRUCTURAL MEMBER IS TWISTED
• TORSIONAL FORCES


  PRODUCE ROTATIONAL MOTION ABOUT THE LONGITUDINAL AXIS OF ONE END OF THE MEMBER RELATIVE TO THE OTHER END.
• TORSIONAL TEST


  PERFORMED ON CYLINDRICAL SOLID SHAFTS/TUBES.
• STRESS-STRAIN BEHAVIOR


  DEGREE TO WHICH A STRUCTURE DEFORMS OR STRAINS DEPENDS ON THE MAGNITUDE OF AN IMPOSED STRESS.
• HOOKE'S LAW (O = )

  Ee
• CONSTANT OF PROPORTIONALITY

  Y
• ELASTIC DEFORMATION


  DEFORMATION WHERE STRESS AND STRAIN IS PROPORTIONAL
• ELASTIC DEFORMATION


  WILL GO BACK TO ITS ORIGINAL FORM AFTER STRESS IS REMOVED
• UNTIL WHAT IS THE LIMIT OF ELASTIC DEFORMATION?

  0.005
• STRESS


  MEASURE OF THE INTERNAL RESISTANCE OF A METAL TO THE DEFORMATION UNDER A FORCE
• STRAIN


  MEASURE OF THE DEFORMATION OR CHANGE IN SHAPE THAT A MATERIAL UNDERGOES IN RESPONSE TO APPLIED STRESS.
• STRAIN


  DIMENSIONLESS QUANTITY
• PLASTIC DEFORMATION


  DEFORMATION IS RETAINED OR IT IS IRREVERSIBLE
• ELASTICITY


  A MATERIAL PROPERTY IN WHICH THE MATERIAL RETURNS TO ITS ORIGINAL SHAPE AFTER STRESS HAS BEEN APPLIED THEN REMOVED
• YOUNGS MODULUS


  RATION OF STRAIN OVER STRESS
• BENDING


  DEFORMATION CAUSED BY A COMBINATION OF TENSION AND COMPRESSION FORCESS ACTING ON A STRUCTURE, RESULTING IN CURVATURES OR FLEXURES.
• TURNING FORCE CAUSED BY A FORCE ACTING ON AN OBJECT AT SOME DISTANCE FROM A FIXED POINT.

  MOMENT
• FORCES PRODUCES A MOMENT OR TURNING FORCE THAT TRIES TO ROTATE THE DIVIDING BOARD AROUND A FIXED POINT IN THIS CASE, THE MOMENT BEND THE DIVIDING BOARD

  MOMENT OR TURNING FORCES
• POISSONS RATIO


  MATERIAL PROPERTY THAT CHARACTERIZES HOW A MATERIAL DEFORMS IN RESPONSE TO AN APPLIED UNIAXIAL STRESS.
• YIELDING


  POINT AT WHICH A MATERIAL UNDERGOES PLASTIC DEFORMATION UNDER STRESS BUT RETURNS AFTER STRESS IS REMOVED