ASTM F2777 knee bearing (tibial insert) endurance fatigue test and deformation under high flexion

Used to evaluate the durability and deformation performance of knee joint pads under high bending load conditions. It simulates the stress and deformation of the knee joint during daily activities, such as walking, running, and the impact and pressure experienced during sports. During the tests, specific testing equipment and simulated physical movements are used to apply continuous and high-frequency loads to the knee joint, mimicking actual usage scenarios. By assessing the performance variations of knee joint pads under different bending cycles, such as deformation resistance, rebound performance, and durability, it is possible to determine the quality and lifespan of the pads, providing a basis for the design and improvement of knee protection products. This testing method is of great significance for the research and development as well as quality control of knee protection devices and sports goods.

For this mechanical test, a maximum bending angle and a rotation of the tibial insert (internal rotation of 20°) around the superior-inferior axis must be selected. 

The yield performance in the worst-case scenario is determined after a dynamic load of 220,000 N for 2,275 cycles.To assess the creep performance, the change in play between the tibial base plate and the insert is measured before and after the high flexion fatigue test. 

Additionally, before and after the fatigue test, the "AP Pull Test" and the "Rotational Play Test" (according to ASTM F1223) are carried out and compared to each other.The values expressed in SI units should be accepted as standard. No other units of measurement are included in this standard.

UnitedTest UTDS series electromagnetic equipment provides precise sine wave load control, offering comprehensive testing tooling to meet the experimental condition requirements in the standards, as well as accurate and effective experimental plans (SOP), helping in the mechanical performance analysis of tibial braces.