TESTING SERVICES
The lab at FTA employs automated techniques developed by Keith Donald for a variety of
fracture mechanics applications, including fatigue crack growth rate testing (ASTM E647)
and non-linear fracture toughness testing (ASTM 1820 and 1921). Both steady state and variable
amplitude methods are supported.
Capabilities
Testing is carried out on ten computer-controlled servo-hydraulic
mechanical test systems, with load capacities up to 50,000 lbs. Each load frame has
a selection of load cells for
precision load control.
Temperature capability of -300 degrees F to +1900 degrees F is available. We have a full assortment fixturing
available for common test geometries including
compact tension, surface flaw, center crack, corner crack, single edge crack, and bend bars. Testing is possible in a wide variety of environments, including high humidity and
saltwater.
All frames are controlled using
FTA's proprietary software and systems.
Testing techniques
Standard ASTM E647 testing is carried out under K-control (constant R or constant Kmax) and constant load. Customers
are typically provided with a complete da/dN curve including near-threshold, region II and region III data.
Specialty testing to customer requirements is available.
We also routinely offer:
- variable amplitude loading with automated crack monitoring and endpoint validation
- dwell testing and custom waveforms
- small crack testing, including surface flaw
- non-linear fracture toughness testing, including cyclic J
Crack lengths are monitored using compliance and
DC potential drop techniques.
Testing is carried out according to well-documented procedures made available to customers
at all times. Procedures are unique to to each program and are derived from best practice;
applicable ASTM standards; and particular customer requirements.
