Dynamic Fatigue Testing Machine – QualiDFT™ Series
The QualiDFT™ Series Dynamic Fatigue Testing Machine provides precise, high-frequency cyclic loading for material characterization, component validation, fatigue life evaluation, and fracture mechanics research. Built around a floor-standing servo-hydraulic load frame, the series is available in 25 kN, 50 kN, 100 kN, 250 kN, and 500 kN capacities to accommodate different specimen dimensions and testing forces. Each model supports tension-tension, tension-compression, and fully reversed fatigue testing for metals, polymers, composites, and biomedical materials.
The floor-standing load frame places the dynamic actuator at the base, providing a low center of gravity that helps reduce vibration and maintain accurate specimen alignment during cyclic loading. A high-performance hydraulic actuator with a ±75 mm stroke delivers controlled sinusoidal, triangular, and user-defined waveforms across frequencies suitable for both low-cycle and high-cycle fatigue testing. Closed-loop servo-hydraulic control works with a fatigue-rated load cell and optional extensometer to maintain accurate force, displacement, or strain control throughout each test.
The QualiDFT™ Series offers five load capacities to match different fatigue testing requirements. The 25 kN and 50 kN models are suitable for thin-gauge metals, polymers, and small composite coupons. The 100 kN model is designed for standard metallic fatigue specimens, including testing in accordance with ASTM E466. The 250 kN and 500 kN models provide the higher force capacity required for thicker specimens, structural joints, and full-scale component fatigue testing.
All five models use a common controller platform, software environment, and grip interface, making it easier to scale testing capacity while maintaining a consistent operating workflow. The QualiDFT™ Series is suited for dynamic material testing, fatigue strength testing, cyclic loading, fatigue life studies, and component durability evaluation across research and industrial laboratories.
Dynamic Fatigue Testing Machine – QualiDFT™ Series Applications
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Aerospace Structural Materials: Generates S-N curves and crack growth data for aluminum alloys, titanium, and nickel-based superalloys used in airframe structures, turbine components, and landing gear. Supports fatigue and fracture mechanics testing in accordance with ASTM E466 and ASTM E647.
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Automotive Component Development: Evaluates the cyclic durability of suspension arms, drivetrain shafts, fasteners, welded joints, and other components under constant or variable loading conditions that simulate road-service stresses.
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Metal and Alloy Research: Measures fatigue strength, endurance limits, and strain-life characteristics of ferrous and non-ferrous alloys for material development, performance evaluation, and specification compliance.
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Composite Materials Evaluation: Performs tension-tension fatigue testing on fiber-reinforced polymer laminates, composite coupons, and sandwich panels in accordance with ASTM D3479 and ISO 13003 for applications including aerospace and wind energy.
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Biomedical Implant Validation: Supports fatigue testing of spinal fixation systems, hip stems, knee components, bone plates, and dental implants according to applicable standards such as ASTM F1717, ASTM F2077, and ISO 14801.
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Weld and Joint Qualification: Tests butt welds, fillet welds, and adhesive-bonded joints under constant-amplitude or variable-amplitude cyclic loading to evaluate fatigue performance and verify joint designs against specified requirements.
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Fracture Mechanics and Crack Growth: Determines crack growth behavior by measuring da/dN versus ΔK using compact tension (CT) and middle tension (MT) specimens in accordance with ASTM E647. These results support damage-tolerance assessments and fatigue crack inspection planning.
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Fastener and Spring Testing: Evaluates the fatigue life of bolts, screws, rivets, springs, and other mechanical elements under axial or combined loading. Results help support quality control, durability assessment, and component design optimization.
Standards
The QualiDFT™ Series Dynamic Fatigue Testing Machine supports fatigue, cyclic loading, and fracture mechanics testing in accordance with a range of international and industry standards, including:
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ISO 1099 – Metallic Materials: Fatigue Testing – Axial Force-Controlled Method
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ISO 12106 – Metallic Materials: Fatigue Testing – Axial Strain-Controlled Method
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ISO 12108 – Metallic Materials: Fatigue Testing – Fatigue Crack Growth Method
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ISO 7500-1 – Metallic Materials: Calibration and Verification of Static Uniaxial Testing Machines
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ASTM E466 – Standard Practice for Conducting Force Controlled Constant Amplitude Axial Fatigue Tests of Metallic Materials
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ASTM E606 – Standard Test Method for Strain-Controlled Fatigue Testing
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ASTM E647 – Standard Test Method for Measurement of Fatigue Crack Growth Rates
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ASTM E399 – Standard Test Method for Linear-Elastic Plane-Strain Fracture Toughness of Metallic Materials
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ASTM E468 – Standard Practice for Presentation of Constant Amplitude Fatigue Test Results for Metallic Materials
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ASTM D3479 – Standard Test Method for Tension-Tension Fatigue of Polymer Matrix Composite Materials
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DIN 50100 – Fatigue Testing: Execution and Evaluation of Cyclic Tests at Constant Load Amplitudes on Metallic Specimens and Components
Dynamic Fatigue Testing Machine – QualiDFT™ Series Key Features
The QualiDFT™ Series combines a rigid floor-standing load frame, high-performance servo-hydraulic actuator, precision load measurement, and digital control into a scalable platform for dynamic fatigue testing, cyclic loading, and material durability evaluation.
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Floor-Standing Load Frame: Twin-column, floor-standing architecture with a base-mounted actuator provides a stable, low-center-of-gravity structure that helps minimize vibration and maintain specimen alignment during cyclic testing.
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Integrated Digital Controller: Controls waveform generation, data acquisition, cycle counting, and automated test termination. Supports sine, triangle, square, and user-defined waveforms with configurable failure criteria.
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Crosshead Lifting and Locking: Motorized crosshead adjustment and hydraulic locking enable fast positioning for different specimen lengths and fixture configurations without manual shimming.
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Interchangeable Grips and Fixtures: Hydraulic wedge grips, mechanical grips, and custom fixtures support flat and round specimens as well as component testing. Configurations are available for tension, compression, bending, and combined loading applications.
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Dedicated Hydraulic Power Unit: A load-matched hydraulic power unit provides stable oil pressure and flow for the selected frame capacity. Integrated filtration and cooling help support reliable actuator and servo valve operation during extended fatigue tests.
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High-Performance Dynamic Actuator: A fatigue-rated hydraulic actuator with a ±75 mm stroke delivers controlled cyclic movement across the operating frequency range, supporting both high-cycle fatigue testing and low-cycle fatigue tests at slower rates.
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Precision Load Cell: A fatigue-rated load cell with Class 0.5 accuracy per ISO 7500-1 measures axial force with high precision and long-term stability, providing reliable feedback for closed-loop control over extended testing cycles.
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Closed-Loop Servo-Hydraulic Control: Digital PID control and a responsive servo valve regulate force, displacement, or strain according to the selected test mode. The system can compensate for changes in specimen compliance as fatigue damage develops.
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High Frame Stiffness: Frame stiffness ranges from 5 × 10⁸ N/m for the 25 kN to 250 kN models up to 6.5 × 10⁸ N/m for the 500 kN model. High stiffness helps reduce parasitic frame deflection and improves displacement measurement accuracy.
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Wide Vertical Test Space: Vertical clearances range from 1,120 mm on the 25 kN to 100 kN models up to 2,000 mm on the 500 kN model, providing space for tall specimens, environmental chambers, and multi-point bending fixtures.
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Safety and Limit Protection: Integrated emergency stop functions, upper and lower limit switches, and interlock systems help protect operators, specimens, fixtures, and the testing machine against overtravel and unexpected load conditions.
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Scalable Configuration: Five load capacities share a common controller, software environment, and grip interface, allowing laboratories to expand testing capacity while maintaining a consistent operating workflow and accessory setup.
Theory and Method
Fatigue testing evaluates how a material or component responds to repeated cyclic loading over an extended number of cycles. The specimen is subjected to controlled maximum and minimum force, stress, or strain at a defined frequency. With repeated loading, localized deformation can develop within the material, followed by persistent slip bands, micro-crack formation, and progressive crack growth. Eventually, a dominant fatigue crack can propagate until fracture occurs. The relationship between applied stress amplitude and cycles to failure is commonly represented by an S-N curve, which provides an indication of a material's fatigue resistance.
The QualiDFT™ Series uses a servo-hydraulic drive to convert pressurized hydraulic fluid into controlled piston movement. A servo valve regulates hydraulic flow to the actuator in real time, while the closed-loop controller continuously compares feedback from the load cell or extensometer with the programmed test waveform. The controller then adjusts the actuator response to maintain the required force, displacement, or strain within defined limits. This control method supports force-controlled high-cycle fatigue (HCF) testing as well as strain-controlled low-cycle fatigue (LCF) testing, where repeated plastic deformation has a significant effect on fatigue damage.
Fracture mechanics testing provides additional information on fatigue crack propagation and structural integrity. A pre-cracked specimen is subjected to controlled cyclic loading while crack length is monitored using a compliance gauge, potential drop method, or other suitable measurement technique. The resulting crack growth rate (da/dN) can be evaluated against the stress-intensity factor range (ΔK) to characterize fatigue crack growth behavior, including threshold and Paris-law regions and the approach to unstable fracture. These results support damage-tolerance assessment, inspection interval planning, fatigue life prediction, and structural component durability analysis.
Dynamic Fatigue Testing Machine - QualiDFT™ Series Technical Specifications
| Parameter |
QualiDFT™ 25 |
QualiDFT™ 50 |
QualiDFT™ 100 |
QualiDFT™ 250 |
QualiDFT™ 500 |
| Frame Type |
Floor-standing |
| Rated Load (kN) |
25 |
50 |
100 |
250 |
500 |
| Max. Vertical Test Space (mm) |
1,120 |
1,120 |
1,120 |
1,400 |
2,000 |
| Actuator Stroke (mm) |
±75 |
| Working Table Height (mm) |
900 |
1,000 |
| Effective Column Spacing / Test Width (mm) |
540 |
650 |
800 |
| Column Diameter (mm) |
80 |
90 |
110 |
| Base Width, Left-Right (mm) |
1,100 |
1,200 |
1,500 |
| Base Depth, Front-Back (mm) |
800 |
1,000 |
| Overall Height (mm) |
2,700 |
3,100 |
4,200 |
| Frame Stiffness (N/m) |
5 × 10⁸ |
6.5 × 10⁸ |
| Approximate Weight (kg) |
≈1,250 |
≈1,650 |
≈2,100 |
