FtF Fatigue to Fracture (pat.pend.)

Stent Testing


Fatigue to Fracture Tester

Why Fatigue to Fracture is needed

Although most new medical device standards and regulatory guidelines require Fatigue to Fracture (FtF) testing, the most important reason to develop a Fatigue to Fracture program is to ensure that your new product lifetime enhances the company’s reputation and financial success. Properly executed Fatigue to Fracture testing can predict the lifetime of your product. It can also identify locations of future failure and verify Finite Element Analysis (FEA) predictions.

Dynatek Labs offers a real solution

Dynatek Labs has always cast an eye forward to the needs of the future. Although the fundamentals of Fatigue to Fracture are well established, the real innovations center on experimental protocols that result in successful predictions of endurance limits and sites of future failures. Dynatek has developed an instrument, testing protocols, and testing envelopes that address properties of all implantable tubular elements such as stents and endovascular prostheses.

Dynatek Labs radial Fatigue to Fracture device tester can, along with novel mock arteries, deliver cyclic pressures up to 50 psi (2500 mmHg).

Testing Advantage

A properly designed and executed Fatigue to Fracture evaluation can predict:

1. Endurance limits by varying the load, frequency of test, temperature or pH
2. Predict potential failure locations of the device
3. Verify (or not) the validity of a Finite Element Analysis

Fatigue to Fracture (FtF) has

• Extremely strong stainless manifold capable of 2000 psi loading

• Unique bellows design allowing lifetimes of up to 1 billion cycles before failure

• Components that can withstand up to 60 °C temperature and pH 12.0

• High pressure capacitance tank with a view window and electronic fluid level monitor

• Custom designed electromagnetic motor that delivers years of service

• State of the art explosion proof case (optional), that cannot be tampered with, to maximize the safety of the operators or observers

• Handy computer and controller cart that lets the user choose options for comfort and useability

Fatigue to Fracture Tester
Complete FtF tester.
Fatigue to Fracture Tester
High-pressure capacitance tank with observation window and float switch.
Fatigue to Fracture Tester
Proprietary LabView-based controller software.


Perhaps the most impressive component of the Fatigue to Fracture instrument is our Universal Software that controls and monitors all experimental parameters and records them as frequently as once per minute. LabView-based programming coupled to a powerful SBRIO and FPGA has extraordinary capabilities to control, monitor and record each moment of an experiment.

“Engineers know that this kind of tester is absolutely vital to developing a long life implantable device.”

As you can see in the photos, the Dynatek Fatigue to Fracture tester is an impressive, strong and powerful instrument. Not just built for endurance testing, it includes a safety enclosure that ensures operator safety.

The second part of the story is focused on the unique mock artery system that we have developed. By using a combination of outer and/or inner mock vessel you can:

1. Produce agressive contraction only loading
2. Produce agressive expansion only loading
3. Produce agressive expansion and contraction loading

The Dynatek Fatigue to Fracture tester is a unique and effective way to carry out predictory Fatigue to Fracture testing on vascular stents, endovascular prothesis (or other tubular elements that may not be a medical device). This instrument is the latest in a series of historic contributions that Dynatek Labs has been responsible for over the past 30 years.

Dynatek personnel will custom design any protocol or instrument to meet your needs.

Fatigue to Fracture Tester
The FtF tester supports up to six samples.
Fatigue to Fracture Tester
Optional safety enclosure.

 Dynatek Labs FtF Product Specifications

# of samples
≤ 6
Sample diameter
1-8 mm ID
Sample length (straight)
≤ 250 mm
Sample configuration
linear for easy photography
stainless steel, proximal and distal
Capacitance tank
reinforced stainless steel with observation window and float switch
Pressure transducer
high pressure / high resolution
Temperature range
room temp to 60 °C
pH range
5.0 to 12.0
Sample temperature control
24v circulatory pump
Systemic pressure
up to 28 psi
Control system
Dynatek’s Universal Controller
Variables controlled and/or monitored
temp, cycle rate, cycle count, systemic pressure, sample pressure
CE mark
Safety enclosure
Alcoholic cleaner and sterilant
Freq. of pertinent data stored
≥ 1 min
Test samples of various dimension
Power required
120/240 V 60/50 Hz
Unattended operation
Ionic solution restriction
chloride levels < 0.2 M
Testing modes
sample deflection or pressure 1
< 60 dBA

1Sample deflection monitoring requires optional high speed camera.
Specifications are subject to change without notice.

Dynatek Labs, Inc.
105 East 4th Street
Galena, MO 65656
fax 417.357.6327

Leading the World in Medical Device Testing