Biomaterials freeze over a temperature range, during which their mechanical properties changedramatically. Young '5 modulus of the tested biomaterial (potato tissue) increases almost three ordersof magnitude as temperature is decreased below freezing. This change is not proportional to thefraction of ice formed. The relaxation of the material is initially faster as more ice is formed, an effectattributed to faster relaxation of ice. When the ice formation is complete, further lowering oftemperature makes the relaxation slower, an effect attributed to temperature itself as distinct fromchange of phase. As the temperature lowers, more ice forms and the material behaves more brittle,decreasing the failure strains. The compressive and tensile failure strength increases with drop intemperature. The energy to failure drops significantly with decrease in temperature and increase instrain rate.
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