It can also function to conduct conventional ASTM E8[2] tensile tests; ASTM F519[3] 200-hr Sustained Load Tests with subsequent programmable step loads to rupture for increased reliability; and ASTM G129 Slow Strain Rate Tensile tests.
It is imperative that the load increases do not overshoot the next elevation in applied stress.
Once this is achieved, repeatability is good with variance in the low single digits that are probably related more to surface roughness, internal defects, and other intrinsic material properties differences rather than the testing equipment.
Precision in controlling the load allows for greater sensitivity in measuring crack extension via load drop and compliance correlation than obtainable with high-voltage electrical resistivity measurements and eliminates the need for clip gages.
This capability allows for precise electronic detection of the maximum load required for Crack Tip Opening Displacement calculations of Fracture Toughness and precise detection of the onset of crack growth required for measurement of the threshold stress for hydrogen embrittlement, environmental or stress corrosion cracking.