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1

Experimentation and Prediction of the Wear of a Cutting Tool in Turning Process

Merzoug M., Benamara N., Boulenouar A., Bouchouicha B., Mazari M.

Archives of Metallurgy and Materials

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2018

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Vol. 63, iss. 2

563--573

EN

In the present work, the performance of multilayer coated carbide tool was investigated considering the effect of cutting parameters during turning of 34CrMo4 Low alloy steel. It has high strength and creep strength, and good impact tenacity at low temperature. It can work at –110°C to 500°C. And EN 10083-1 34CrMo4 owns high static strength, impact tenacity, fatigue resistance, and hardenability; without overheating tendencies. The objective functions were selected in relation to the parameters of the cutting process: surface roughness criteria. The correlations between the cutting parameters and performance measures, like surface roughness, were established by multiple linear regression models. Highly significant parameters were determined by performing an Analysis of variance (ANOVA). During the experiments flank wear, cutting force and surface roughness value were measured throughout the tool life. The results have been compared with dry and wet-cooled turning. Analysis of variance factors of design and their interactions were studied for their significance. Finally, a model using multiple regression analysis between cutting speed, fee rate and depth of cut with the tool life was established.

2

A strain energy density theory for mixed mode crack propagation in rubber-like materials

Boulenouar A., Benseddiq N., Merzoug M., Benamara N., Mazari M.

Journal of Theoretical and Applied Mechanics

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2016

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Vol. 54 nr 4

1417--1431

EN

In this paper, a numerical modeling of crack propagation for rubber-like materials is presented. This technique aims at simulating the crack growth under mixed-mode loading based on the strain energy density approach. At each crack increment length, the kinking angle is evaluated as a function of the minimum strain energy density (MSED) around the crack tip, using the Ansys Parametric Design Language (APDL). In this work, numerical examples are illustrated to demonstrate the effectiveness, robustness and accuracy of the computational algorithm to predict the crack propagation path. The results obtained show that the plan of crack propagation is perpendicular to the direction of the maximum principal stretch. Moreover, in the framework of linear elastic fracture mechanics (LEFM), the minimum values of the density are reached at the points corresponding to the crack propagation direction.

3

FE model for linear-elastic mixed mode loading: estimation of SIFs and crack propagation

Boulenouar A, Benseddiq N., Mazari M, Benamara N

Journal of Theoretical and Applied Mechanics

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2014

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Vol. 52 nr 2

373--383

EN

Finite element analysis combined with the concepts of linear elastic fracture mechanics provides a practical and convenient means to study the fracture and crack growth of materials. The onset criterion of crack propagation is based on the stress intensity factor, which is the most important parameter that must be accurately estimated and facilitated by the singular element. The displacement extrapolation technique is employed to obtain the SIFs at crack tip. In this paper, two different crack growth criteria and the respective crack paths prediction for several test cases are compared between the circumferential stress criterion and the strain energy density criterion. Several examples are presented to compare each criterion and to show the robustness of the numerical schemes.