Adhesion, plasticity and other peculiar properties of solid methane

Adhesion and plasticity of polycrystalline solid methane have been studied in the temperature range 10–90 K. It was shown that adhesion is very strong in the 50–90 K temperature range where the solid methane is soft and sticky. Closer to the melting point (at 90.6 K) the solid methane behaves as extremely viscous non-Newtonian liquid. Below 30 K solid methane loses its stickiness and ductility and acts like ordinary glass. Methane adhesion remains similar for very different materials. We have also made some video observations which reveal unexpected and mostly inexplicable properties of solid methane which could be of some interest for designing new methane moderators for neutron sources and planetary physics particularly the study of the environment of Titan.

► We measured adhesion and plasticity of solid methane at temperatures 10–90 K. ► Near melting point solid methane behaves as viscous non-Newtonian liquid. ► We present video observations which reveal unexpected properties of solid methane. ► Results could be used for designing new methane moderators for neutron sources. ► Presented data are important for planetary research particularly Titan environment.