Testing of mechanical and technological properties

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Testing of mechanical and technological properties
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Mechanical properties
Stress and strain These are
size-independent measures of load and
displacement, respectively.
Elastic behavior This reversible behavior
often shows a linear relation between
stress and strain. To minimize deformation,
select a material with a large elastic
modulus (E or G).
Plastic behavior This permanent deformation
behavior occurs when the tensile (or
compressive) uniaxial stress reaches sy.
Toughness The energy needed to break a unit
volume of material.
Ductility The plastic strain at failure.
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Mechanical properties - testing

• Type of loading
• Static
• Dynamic
• Type of testing techniques
• Destructive
• most methods of mechanical testing
• Nondestructive
• Semidestructive
• hardness (indentation methods)

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Mechanical properties - testing

• Mode of loading
• Tension
• Compression
• Share
• Bend
• Torsion
• Combination

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Mechanical properties - testing

• Measured characteristic
• What i wont to know (measure)
• How it measure - vote of appropriate method
• There is no fully universal testing method!

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Mechanical properties - testing

• Standard testing method
• Tensile test
• Hardness measurement
• Charpy or Izod impact test
• Sophisticated testing method
• Fracture mechanic
• Fatigue testing
• Creep and relaxation behavior
• Etc.

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Mechanical properties - testing

• Tensile test
• Yield stress, ultimate stress, elongation, area
  reduction, modulus of elasticity, stored energy
• Hardness measurement
• Static methods
• Vickers, Rockwell, Brinell
• Dynamic methods
• reflection (Shore), Poldi hammer, Baumann hammer

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Mechanical properties - testing

• Charpy impact tests dynamic

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Mechanical properties - testing

• Charpy impact tests
• Impact energy K J
• Shape of the notch
• KU or KV
• Impact toughnes

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Mechanical properties - testing
Transition temperature (from ductile to brittle
fracture
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Mechanical properties - testing

• Fracture toughnes testing

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Mechanical properties - testing

• Fracture toughnes testing

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Mechanical properties - testing

• Fatigue testing

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Mechanical properties - testing

• Fatigue testing S-N (Wöhler) curve

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Mechanical properties - testing

• Creep resistance
• Creep is a time-dependent deformation of a
  material while under an applied load that is
  below its yield strength.

Parametres Temperature Stress Time Deformation
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Nondestructive testing methods

• detection of surface, close under surface
• and in bulk defects
• Cracs
• Pores
• Inclusions

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Nondestructive testing methods

• Microscopy surface defects
• Penetrating method - surface defects
• Electromagnetic methods - surface and
  undersurface
• Radiographic in bulk defects
• X-ray, ?-ray
• Ultrasonic in bulk defects

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Nondestructive testing methods
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Testing of technological properties

• Technological testing
• mostly tests of suitability of material for
  required technological operation
• Casting
• Forging
• Welding
• Hot or cold working
• Machineability

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Technological properties

• Casting
• Fluidity test

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Technological properties

• Forging
• Upset test
• Punching test
• Plying test
• Etc.

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Technological properties

• Welding tests
• Hot cracking
• Cold cracking
• Ebritlement
• Bending tests
• Etc.

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Technological properties

• Hot and cold working
• testing of semiproducts
• sheets, pipes, wires
• Sheet testing
• Erichsen test

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Technological properties

• Pipe testing
• Compresion test
• Flanging test
• Flaring test
• Pipe testing

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Technological properties

• Machineability testing
• Compresion test
• Flanging test
• Flaring test