Multiaxial high cycle fatigue test system

A multiaxial high cycle fatigue test system for testing bending, torsion, and tension of a test unit, comprising:

• servo-hydraulic components, including a hydraulic service manifold, two small high frequency actuators along a first axis, and one large main actuator along a second axis;
• wherein the large main actuator is used to apply a radial centrifugal force, and the two small actuators are used to apply vibratory loading;
• the two small side actuators being offset independently of each other, to enable the machine to apply both bending loads and torque to the test unit;
• the test unit being subjected to torsion loading when the traverse actuators move in phase, that is when both actuators move either in or out at the same time, and the test unit being subjected to bending loading when the actuators move out-of-phase, that is one actuator moves in when the other moves out or vice-versa.

A method of testing a test unit for bending, torsion, and tension, comprising:

• using servo-hydraulic components, including a hydraulic service manifold, two small high frequency actuators along a first axis, and one large main actuator along a second axis;
• using the large main actuator to apply a radial centrifugal force, and using the two small actuators are to apply vibratory loading;
• the two small side actuators being offset independently of each other, to enable the machine to apply both bending loads and torque to the test unit;
• subjecting the test unit to torsion loading when the traverse actuators move in phase, that is when both actuators move either in or out at the same time, and subjecting the test unit to bending loading when the actuators move out-of-phase, that is one actuator moves in when the other moves out or vice-versa.