Mechanical Testing: Nanoscale to Macroscale

The core is equipped to perform material property testing of hard and soft biological and nonbiological tissues. This includes basic compression, tensile and torsion testing; cyclic fatigue testing; evaluation of viscoelastic response (quasistatic and high frequency); hardness testing (both conventional and nanoindentation); and application of complex loading on cadaveric specimens and biomedical devices.

Testing services have been provided for a wide array of projects. Examples include evaluating aortic leaflet stiffness, fatigue properties of pelvic mesh materials, dynamic stiffness of imaging phantom model materials, pull-out resistance of orthopedic hardware, hardness of trabecular bone in animal models of osteoporosis and compressive properties of tissue-engineered cartilage.

Three servohydraulic biaxial (axial/torsional loading) material testing machines:

  • Model 312 (MTS Systems Corp.)
  • Model 858 Mini Bionix II with environmental chamber (MTS Systems Corp.)
  • Model 1321 (Instron)

The laboratory also operates an ElectroForce 3200 electromechanical testing system (Bose Corp.) with dynamic mechanical analysis (DMA) capabilities.

Using a Hysitron TI 950 TriboIndentor nanoindentation system, the core laboratory can perform nanoscale testing of materials. This service has been used to examine bone intrinsic properties of bone trabeculae and polymer materials.

The laboratory also maintains several pieces of custom test equipment capable of cyclic wear testing of articular implants, simulating spine loading and kinematics, assessing mechanical properties of long bones in animal models, and other unique applications.

An extensive variety of sensors are available for measuring forces (single axis to 6-component); pressures (Tekscan and fiber optic sensors); and linear displacement and angular rotations.

Full strain and deformation fields of objects can be captured with the laboratory's digital image correlation (DIC) camera system (ARAMIS 3D Real Time 4M).