الفهرس 
CHAPTER 1: INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Abrasive water jet machining (AWJM) is one of the most recently advanced non-conventional industrial technologies. It has been increasingly applied in
manufacturing due to its different distinct benefits over the other machining technologies. Though, many aspects of this technology need to be deeply understood to improve its ability and machining performance as well as to optimize the machining operation.
This study includes an extensive review of literature on the investigations of the different aspects of AWJ cutting of carbon fiber reinforced plastic composites
(CFRPCs). It shows that while considerable studies have been carried out, insufficient studies have been found on the AWJ contouring process although it is a common AWJM application. For the nature of the AWJM process, the changing nozzle traverse direction included in AWJ contouring causes in kerf geometrical or shape errors. In-depth
knowledge of the AWJ contour making operation is important for a decrease or the reduction of these shape errors. Accordingly, a detailed experimental investigation is presented in this study to analyze the different machining performance measures in AWJ contouring of
CFRPCs over a wide range of process parameters. For a comparison purpose, the study also consider AWJ straight-slit cutting.
An experimental study of AWJ straight-slit cutting (kerf) and profile cutting or contouring (square opening, hole opening, and external curvature) of CFRPCs is presented based on a statistically designed experimental investigation. The
scope of the experimental study includes an investigation of the cut
characteristics and the effects of the various major process parameters on
technological performance measures.
The experimental results are used to optimize the AWJ straight-slit cutting
using the Taguchi method combined with a grey relational analysis (GRA)
approach. Predictive empirical models (second-order polynomial) in conjunction with generalized reduced gradient (GRG) algorithm and desirability function are
used for single and multi-response optimization of AWJ contouring.
It shows that the models can adequately predict the machining performance qualities and form the essential basis for developing strategies for selecting the optimal process parameters in AWJM.
The influences of process parameters on the major cutting performance
measures in AWJ contouring of CFRPCs have been carefully considered and
analyzed.
The cutting parameters involve the AWJ contouring making in a way similar
to that in the straight making.
The investigation has provided a guide for the choice of process parameters in the AWJ contouring of CFRPCS.
An examination of the kerf taper produced in AWJ contouring has attained that the overall shape looks like that in straight cutting.
It also indicates that a lack of knowledge of the AWJ characteristics has limited the development of machining performance models that are necessary for process adaptation and optimization.
The effects of process parameters, such as water pressure, abrasive mass
flow rate, standoff distance and, nozzle traverse speed, on the AWJ contouring process, are similar to that in AWJ straight cutting.