Determine crack toughness and crack propagation

Determine crack toughness and crack progress

Determination of fracture mechanic values

 

Characteristic values for the fracture toughness are required for the characterization of the material resistance for fracture mechanical calculations. The crack toughness is determined on the basis of laboratory samples in standardized tests. We are able to determine:

  • the stress intensity factor K (Linear Elastic Fracture Mechanics),
  • the J-interal or
  • the Crack Tip Opening Displacement (CTOD)

For the service life calculation, other parameters are required to describe the crack propagation rate (Paris equation with parameters m and C and DeltaKth or NASGRO equation with other parameters). These are also determined using laboratory samples according to recognised standards.

 

In dialogue with our customers, we organise and perform the above-mentioned fracture mechanics tests. We carry them out in cooperation with the Steel Instituteat RWTH Aachen University. We then evaluate the results according to current standards. We perform tests according ISO 12135, ISO 12137 (weldments), ASTM E 399, ASTM E 1820, ASTM E 647, BS 7448-1, BS7448-2.

Fracture mechanics specimens, scalable in size
Fracture mechanics tests at low temperatures down to -196°C