ASTM E1820 covers procedures and guidelines for the determination of fracture toughness of metallic materials using K, J, and CTOD (d). Toughness can be measured in the R-curve format or as a point value. The fracture toughness determined in accordance with ASTM E1820 is for the opening mode (Mode I) of loading.
The objective of ASTM E1820 is to load a fatigue precracked test specimen to induce either or both unstable crack extension, including significant pop-in, referred to as fracture instability in ASTM E1820; and stable crack extension, referred to as stable tearing in ASTM E1820. Fracture instability results in a single point-value of fracture toughness determined at the point of instability. Stable tearing results in a continuous fracture toughness versus crack-extension relationship (R-curve) from which significant point-values may be determined. Stable tearing interrupted by fracture instability results in an R-curve up to the point of instability.
For ASTM E1820, use a fatigue test machine. You may pair the test machine with fracture, bending or tension clevis grips as well. By means of our testing expertise and modular product design, we will help find the testing solution that is right for you. Give one of our application engineers a call today for help with creating the best budget and testing plan according to ASTM E1820.
Recommended Test Machines
Force range of 5 kN to 600 kN (1,125 lbf to 135,000 lbf)
Adjustable test space
The most popular choice for static tension and compression tests
These dual column testers are available in both tabletop and floor standing models
Static and fatigue forces up to 50 kN (11,250 lbf)
Frequency ratings up to 75 Hz
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Static and fatigue forces up to 25 kN (5,500 lbf)
Frequency ratings up to 100 Hz
Servohydraulic
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Recommended Testing Accessories
Rated from -40°C to 150°C (-40°F to 300°F)
Clevis design
Maximum specimen widths from 12.7 mm to 50.8 mm (0.50 in. to 2.00 in>)
Pin diameters from 12.7 mm to 50.8 mm (0.50 in. to 2.00 in.)
Load ratings up to 250 kN (56,250 lbf)
Base lengths up to 1200 mm (48 in)
Various roller sizes available
Available in 3-point and 4-point configurations
Load ratings up to 10 kN (2,250 lbf)
Interchangeable roller diameters from 1 mm to 12.7 mm (0.04 in to 0.5 in)
Easily adjustable span
Base lengths of 150 mm (6 in) and 300 mm (12 in)
Measures displacement between the two mounting arms
All models capable of operating at frequencies of at least 50 Hz
All standard models rated between -40°C to 100°C (-40°F to 210°F)
Wide range of specimen sizes available
