Background: The shear properties of rigid polyurethane (PU-R) foams, routinely used to simulate cancellous bone, are not well characterized. Method of approach: The present assessment of the shear and compressive properties of four grades of Sawbones “Rigid cellular” PU-R foam tested 20 mm gauge diameter dumb-bell specimens in torsion and under axial loading. Results: Shear moduli ranged from 13.3 to 99.7 MPa, shear strengths from 0.7 MPa to 4.2 MPa. Compressive yield strains varied little with density while shear yield strains had peak values with “200 kgm−3” grade. Conclusions: PU-R foams may be used to simulate the elastic but not failure properties of cancellous bone.

Issue Section:
Soft Tissues
Keywords:
foams, polymers, shear strength, yield strength, compressive strength, biomechanics, bone, torsion, density, shear modulus
Topics:
Bone, Density, Foams (Chemistry), Shear (Mechanics), Shear modulus, Shear strength, Torsion, Urethane foam, Failure, Gages
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 by ASME
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