Some results of the influence of y radiation on the mechanical properties of PoIymethylmethacrylate are presented. Doses of 0, 50, 100, 150 and 200 kGy were employed. The internal friction (loss tangent) and storage shear modulus were measured at temperatures between 173 K and 300 K using a damped torsion pendulum. Compressive tests were made at room temperature with strain rates between 1 . 4 ...

Internal friction of deformed oriented NaCl single crystals has been measured as a function of flow stress, strain amplitude, frequency, temperature and divalent doping. In pure NaCl af er deformation a maximum of internal friction PI is observed at low temperatures. With increasing 1+ Sr doping a second but much weaker peak P2 appears at higher temperatures. The dependencies of PI on the...

Using spheropolygon-based simulations and contact slope analysis, we investigate the effects of surface topography and atomic scale friction on the macroscopically observed friction between rigid blocks with fractal surface structures. From our mathematical derivation, the angle of macroscopic friction is the result of the sum of the angle of atomic friction and the slope angle between the cont...

Abstract The problem of penetration an absolutely rigid round cone shaped indenter into a weighted rock (an axisymmetric plasticity problem) is being solved. Limit load, depending on the angle internal friction rock, adhesion, angular opening at top cone, weight, determined. dependence loading these parameters given.

Viscoelastic materials have a relationship between stress and strain which depends on time or frequency. Anelastic solids represent a subset of viscoelastic materials: they have a unique equilibrium configuration and ultimately recover fully after removal of a transient load. Internal friction refers to the dissipative response of a material when subjected to a sinusoidal deformation. All mater...