nowadays the surface texturing has been widely recognized as a usable capability to improve the tribological systems. in this paper, ultrasonic assisted turning (uat) isperformed to create the micro textures on the flat faces. micro surface texturing ismade on the al7075-t6 by the uat in the face turning process. then, the influences of cutting speed feed, vibration direction and vibration ampl...

superplastic forming (spf) is a manufacturing process utilized in the automotive industry to produce complex geometry aluminum or magnesium alloy components which cannot be fabricated at room temperature. this paper investigates the effects of the die entry radius and the interfacial friction coefficient on the required forming time and thickness distribution of a superplastic formed part. a co...

the incremental sheet metal forming (ismf) process is a new and flexible method that is well suited for small batch production or prototyping. this paper studies the use of the finite element method in the incremental forming process of aa1050 sheets to investigate the influence of tool diameter, vertical step size, and friction coefficient on forming force, spring-back, and thickness distribut...

This article describes fretting behavior of zirconia and silicon nitride balls on an electro-deposited coating. Fretting tests are performed using a ball-on-flat configuration. The evolution of the kinetic friction coefficient is determined, along with slip ratio. Experimental results show that the steady-state friction coefficient between ceramic balls (Si₃N₄ and ZrO₂) and an electro-deposited...

In the discrete element simulation of granular materials, the modelling of contacts is crucial for the prediction of the macroscopic material behaviour. From the tribological point of view, friction at contacts needs to be modelled carefully, as it depends on several factors, e.g. contact normal load or temperature to name only two. In discrete element method (DEM) simulations the usage of Coul...

Cf = skin friction coefficient CD = drag coefficient CDf = friction drag coefficient CDp = pressure drag coefficient h = step height M0 = freestream Mach number Patm = atmospheric pressure Pi = stagnation pressure Re = freestream Reynolds number Ti = stagnation temperature U = velocity U = normalized velocity Uτ = friction velocity X = longitudinal coordinate Z = vertical coordinate Z = normali...