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This paper is an investigation of detaching phenomena of a trapezoidal cutting blade on a wedged surface of a thin work sheet. To study critical conditions for cutting off an aluminum sheet, the wedged profile of the work sheet was experimentally studied by varying the tip thickness of the trapezoidal cutting blade, which simulated a crushed bevel blade. To analyze the detached condition and separation force of the wedged sheet, an elastoplastic finite element program was used to analyze wedge indentation to the work sheet. The following results were obtained: (i) the deformation of the wedged sheet can be classified in four patterns; (ii) the critical condition for cutting off the work sheet depends on the ratio of tip thickness by sheet thickness w/t; (iii) the separation of the work sheet occurred statistically for w/t = 0.13 ∼ 0.28; and (iv) the separation line force can be used to explain the necking mode and the detached condition.

This paper aims to describe an in-plane detaching resistance of a white-coated paperboard subjected to a peeling deformation. Since the paperboard is composed of fibrous plies, its detaching mechanism seems to be different from a crack propagation of a fragile material. In this work, an internal breaking criteria and transient de-lamination of a weak-bonded layer of paperboard was experimentally investigated through a peel cohesion test (PCT), and its detaching resistance was estimated with a fluffing model using a finite element method (FEM) code to characterize the peeling deformation of the weak-bonded layer. A white-coated paperboard of 0.45 mm thickness (basis weight of 350 gm 2 ) was chosen for conducting a PCT and z-directional (out-of-plane) tensile test (ZDTT). The relationship between the pulling force and curvature of delaminated upper layer of the paperboard were discussed; moreover, the anaphase yielding resistance of detaching was analyzed through ZDTT. The peeled deformation of PCT was analyzed using the isotropic elasticity FEM model, which was developed through the ring crush test. The results were as follows: (1) The in-plane detaching resistance of whitecoated paperboard by PCT is experimentally characterized for observing with the maximum peak at early stage and the stationary line force. These line forces are almost independent of the paper-making direction. (2) A fluffing profile of the de-laminated layer and the thickness of the peeled upper layer experimentally depend on the pulling velocity. (3) Regarding the detaching resistance of peeled layer, a fluffing model was proposed in the developed simulation model. Equivalent fibers based fluffing model that were derived from a ZDTT experiment (approximated as discretely distributed nonlinear springs) well explains the existence of the peak point of peeling force and saturated peel resistance.

This paper reports on the cutting characteristics of a polycarbonate (PC) sheet stacked on a flexible underlay by a wedge indentation. In order to investigate the effect of underlay stiffness on sheared profile of PC sheet, the stiffness ratio k r in the thickness direction was varied. Indentation of a 42° center bevel blade into a 0.5mm thickness PC sheet that was stacked on the flexible underlay was carried out experimentally and numerically. Deformation profile of wedged PC sheet was observed by a CCD camera in order to reveal the effect of underlay on the cutting performance of the PC sheet. On the experimental works, it was found that the underlay mechanical properties affected the cutting load response and deformation features of the PC sheet. To discuss the effect of underlay stiffness on the deformation profile of the PC sheet, a finite element method (FEM) analysis with elasto-plastic model was conducted. Through the experiment and FEM simulation, it was revealed that the deformation profile of wedged PC sheet was remarkably related to the bent-up angle of the PC sheet, which was mainly caused by sinking and lateral elongation of the underlay. Moreover, in order to obtain a smart profile of the PC sheet, the stiffness ratio k r must be chosen in a suitable range.

Gelatin blended with carboxymethylcellulose (CMC) scaffold was fabricated via freeze drying method. The various gelatin and CMC ratios were 100/0, 90/10, 80/20, 70/30 and 60/40, respectively. The mechanical characterization of the scaffold was done by compressive test using universal testing machine. The obtained data was used to determine compressive modulus and shear modulus which was analyzed from neo-Hookean model. The deformed scaffold and total strain energy time response were analyzed using finite element model (FEM). The scaffold G73T showed the highest value both compressive modulus (0.53±0.11 kPa) and shear modulus (1.02±0.11 kPa). The results were consistency with FEM that G73T showed the highest range of equivalent elastic strain and the highest value of total strain energy-time response. The results could imply the best condition for scaffold fabrication from mechanical analysis which might suitable for tissue engineering applications.