Numerical simulations of mantle convection with a viscoplastic rheology usually display mobile, episodic or stagnant lid regimes. In this study, we report a new convective regime in which a ridge can form without destabilizing the surrounding lithosphere or forming subduction zones. Using simulations in 2-D spherical annulus geometry, we show that a depth-dependent yield stress is sufficient to...

We analyze a probability of atomic jumps for more than one lattice spacing in activated surface diffusion. First, we studied a role of coupling between the x and y degrees of freedom for the diffusion in a two-dimensional substrate potential. Simulation results show that in the underdamped limit the average jump length scales with the damping coefficient eta as proportional, v...

Cold rolling of steel is one of the most important metal forming processes so an accurate control of its parameters during the process is necessary. In this paper, the friction coefficient has been proposed as a function of cold rolling parameters such as forward slip, forward and backward tensile stresses ,strip thickness, static deformation, resistance of strip before and after rolling ,strip...

Cold rolling of steel is one of the most important metal forming processes so an accurate control of its parameters during the process is necessary. In this paper, the friction coefficient has been proposed as a function of cold rolling parameters such as forward slip, forward and backward tensile stresses ,strip thickness, static deformation, resistance of strip before and after rolling ,strip...

The relationship between a Lubrication Mode Diagram (LMD) for concentrated contacts (LCC‘s) and the ‘IRG transition’ diaLubrication Modes and the IRG Transition D i ag ram gram has been studied. In addition, scuffing results, obtained by the IRG (International Research Group) have been analysed, as well as the results of scuffing tests performed by different workers using a two-disc apparatus. ...

This paper proposes a method of evaluating the fatigue life of a refrigeration compressor reed valve, given the applied stresses as might be computed by a valve simulation. Mean and alternating values of equivalent stresses (e.g. Von Mises) are plotted in the Haigh diagram. Various choices of models are considered for the safe area of the diagram. This method takes into account surface finish, ...

Friction coefficient and wear rate of different steel materials are investigated and compared in this study. In order to do so, a pin on disc apparatus is designed and fabricated. Experiments are carried out when different types of disc materials such as stainless steel 314 (SS 314), stainless steel 202 (SS 202) and mild steel slide against stainless steel 314 (SS 314) pin. Experiments are cond...

Biomechanical aspects of slips and falls have been widely studied to facilitate fall prevention strategies. Prior studies have shown changes in gait after an induced slipping event. As such, most researchers only slip participants one time to avoid such changes that would otherwise reduce the external validity of experimental results. The ability to slip participants more than once, after allow...

Surface texture of a tool plays an important role as it primarily controls the frictional behavior at the tribo interface. In the present investigation, pin-on-plate sliding tester was used to identify the effect of directionality of surface grinding marks on coefficient of friction and transfer layer formation. 080 M40 steel plates were ground to achieve different surface roughness with unidir...