Mechanical properties of the ice I-magnesium sulfate eutectic: A comparison with freshwater ice in reference to Europa

A systematic series of experiments on laboratory grown ice I-magnesium sulfate (MgSO4·11H2O or MS11) eutectic columnar material and freshwater columnar ice at T = 98 K and T = 263 K directly compare some elastic and inelastic properties of these two materials. The results indicate: (i) that the ice I-MS11 eutectic columnar material (below simply as I-MS11) exhibits bulk elastic properties that are comparable to those of freshwater columnar ice (FWI) at T = 263 K; (ii) that I-MS11 is about 1.6 times stronger under bending, about 1.9 times stronger under compression within the brittle regime and about 1.3 times tougher than FWI at T = 263 K; (iii) that I-MS11 possesses a compressive flow strength within the ductile regime that is about one-half that of FWI at T = 263 K; (iv) that I-MS11 exhibits a transition from ductile-to-brittle behavior at a strain rate that is a factor of about 50 higher than that of FWI at T = 263 K; (v) that I-MS11 has a higher coefficient of kinetic friction at lower temperatures (T = 98 K) and a lower coefficient of kinetic friction at higher temperatures (T = 263 K) and higher sliding velocities (> 10−5 m s−1) compared to FWI. In other words, the results indicate that the mechanical properties of I-MS11 eutectic columnar material are generally comparable to those of freshwater columnar ice, under the conditions examined.