Materials compress each other in a directional material flow, causing energy and momentum to overflow. moving at low velocity outside the boundary of rigid component form finite dissipation zone. A discrete element model is established explore its characteristics. First, mass driven by disk increases linearly with an increase translation distance, significantly. Second, movement state materials...

During fretting, the removal of material by wear leads to an increase of contact stress in the stick zone. If elastic behaviour is assumed, the boundary between stick and slip zones does not move, wear eventually ceases, and a mode-I singularity of contact pressure is predicted after infinitely many cycles. For real materials, the development of singular stresses must be limited by plastic defo...

The built up layer thickness in secondary deformation zone is one of the important parameters in metal cutting process. The built up layer (BUL) is formed in second deformation zone near the tool-chip interface in the back of the chip. This parameter influences the tool life and machined surface quality. This BUL should not be confused with the built up edge (BUE). The deformation of the BUL in...

In this paper Cohesive Zone Model (CZM) concepts are applied in order to study mode I fracture in a pre-cracked bonded Double Cantilever Beam (DCB) specimen. A cohesive surface element is implemented in a Finite Element commercial code using intrinsic cohesive zone models: exponential, bilinear and trapezoidal traction-separation laws. The sensitivity of cohesive zone parameters in predicting t...

In this paper, a numerical model based on the finite difference method is presented to predict tool and chip temperature fields in continuous machining and time varying milling processes. Continuous or steady state machining operations like orthogonal cutting are studied by modeling the heat transfer between the tool and chip at the tool—rake face contact zone. The shear energy created in the p...

Intersonic crack growth has been studied using an interfacial fracture model in which an additional material phase within a bonding layer is proposed to describe the failure behavior of the interface. In this material phase, a strain gradient based damage model is applied with a built-in cohesive law, which is governed by an material intrinsic length scale that bridges the mechanisms that opera...

the used activated carbon was derived from pine-cone and was used for the removal of acid black 1(ab1) and acid blue 113(ab113) dyes. a batch sorption study was carried out in order to obtain optimum isotherm model. the study showed the best fit of the adsorption isotherm data was obtained using the langmuir model for both dyes. the monolayer maximum saturation capacities of ab1 and ab113 dyes ...