Fatigue Crack Growth (FCGR)

Fatigue Crack Growth Rate (ASTM E647)

The FCGR software was designed specifically for fatigue crack growth testing and analysis. Both steady-state (K-control and load control) and variable-amplitude (e.g., flight spectrum, dwell, etc.) applications are available.

The firmware running on the ADwin includes high-priority processes for waveform generation, control and data acquisition. PC software that integrates with the ADwin in real time performs the analysis required to determine crack length, crack closure levels, K-control and da/dN analysis.

Software Features

• Constant-amplitude and variable-amplitude, e.g., flight spectrum testing
• Threshold testing (Region I) and upper-end testing (Paris and Region III)
• Load control and K-control
• Constant K_max testing
• Dwell testing and custom user-defined waveforms
• Compliance and DC potential difference (PD) methods of monitoring crack length
• Up to 8 channels of simultaneous crack growth measurement
• The ability to use a reference PD specimen
• Standard geometries including C(T), M(T), SEN(T), SEN(B), and Kb Bar
• User-defined K lookup and PD lookup tables
• Precise force control
• High-precision 16-bit data acquisition
• Visualization of Load Scan, Load-Displacement, and Load-DCPD graphical displays
• Optimized FTA command-feedback tuning parameters for variable amplitude testing
• Online damage parameter determination for characterizing command-feedback response
• Soft run-stop to minimize the effect of test interruptions
• Crack closure measurement using ASTM opening load
• Adjusted compliance ratio “ACR” integration
• Sine or triangle standard waveforms
• User-defined test frequency via full function generator
• Digital filtering and load-displacement phase shift control
• Data acquisition and analysis optimized according to crack growth rates
• Actual maximum load and cyclic load included in the analysis file for each data point
• Versatile analysis software
• Automated testing via a Matrix utility
• Custom applications
• Run-stop detection from test controller
• Ability to resume testing in the event of a PC crash
• Support of English and SI units