الفهرس Only 14 pages are availabe for public view
 |  | from | 237 |  |  |
| | | from | 237 | | |
Abstract
The main objective of this dissertation is to apply the multi-objective technique in conjunction with fuzzy programming and parametric approach in the field of metal cutting. Three main objective functions, namely, the residual stress, the fatigue life time, and the surface roughness are considered. Two main constraints are also taken into consideration; these constraints are the total force, and the power constraints besides the interval constraints of the input cutting machining parameters, namely, the cutting speed, the undeformed chip thickness, the rake angle, and the wear land length. The optimal solution for every single objective is determined considering the unlubricated case. The efficient solution for the multi-objective models are also studied and analyzed. The relationship between fatigue life and both surface roughness and residual stress was carefully studied. The parametric and the fuzzy approaches are used in case of both the single and multi-objective models. The combined utilization of the fuzzy and the parametric approaches has the ability to provide an efficient tool for describing the relationship between the input machining parameters and the output responses through the utilization of the concept of membership function and the weighting method. The results show through the parametric analysis of the fuzzy models that the different shapes of membership functions with the same lower and upper bounds at certain specific -cut for the decision variables will lead to the same solution vector. It is worth to mention that the solution vector and the response function value are very sensitive to the variations in the number of the decimal points used. The residual stress and the fatigue life function are very sensitive to the small variations in the cutting speed while the surface function is very sensitive to the variations in both the tool rake angle and the cutting speed.