ASTM F543 provides performance considerations and standard test methods for measuring the mechanical properties in torsion of metallic bone screws that are implanted into bone. This test method is intended to measure the uniformity of the product tested or to compare the mechanical properties of different, yet similarly sized products. The following properties may be important when determining the suitability of a screw for a particular application:
Axial Pullout Strength
Insertion and Removal Torque
Self Tapping Force
A torsion testing apparatus is used for applying the required torque to the specimen and calibrated for the range of torques and rotational displacement, along with a suitable testing fixture for the torsional yield strength, maximum torque and breaking angle test. The testing apparatus provides torsional force at a constant rate of 1 to 5 rpm (revolutions per minute). A torque transducer is used to measure the applied torque in the clockwise and counterclockwise rotation that is encountered while performing the test method. Similarly, an Angular Displacement Transducer of some type is used to measure the angle of twist that is calibrated over the range of angles to be encountered in the test with an accuracy of 0.3° (clockwise or counterclockwise rotation).
Solutions for ASTM F543 typically include these types of components:
Load Frame Options
The MTS Acumen® Electrodynamic Test System provides a clean, energy-efficient testing solution for orthopaedic and medical device developers. Models designed for torsion testing integrate a compact electrodynamic axial/torsional load frame, advanced MTS digital controls and powerful TestSuite™ software to provide safe, easy and reliable testing of components and tools subject to torque loading in biomedical service environments.
MTS TestSuite MP provides users the flexibility to create, customize, and share test methods to meet industry-standard testing requirements, and perform a wide variety of more unique and advanced tests. Typical torque/rotation tests, creep testing and bone screw testing are easy to configure using the powerful test creation tools. Alternatively, test engineers can save development time and effort by turning to experience MTS consultants for custom TestSuite methods.