No abstract

No abstract

No abstract

Electric discharge machining (EDM) is a material removal process that is especially useful for difficult-to-cut materials with complex shapes and is widely used in aerospace, automotive, surgical tools among other fields. EDM is one of the most efficient manufacturing processes and is used to achieve highly accurate production. It is a non-contact thermal energy process used to machine electrically conductive components irrespective of the material’s mechanical properties. Studies related to the EDM have shown that the process performance can be considerably improved by properly selecting the process material and operating parameters. This paper reviews research studies on the application of EDM to different grades of stainless steel materials and describes experimental and theoretical studies of EDM that have attempted to improve the process performance, by considering material removal rate, surface quality and tool wear rate, amongst others. In addition, this paper examines evaluation models and techniques used to determine the EDM process conditions. This review also presents a discussion on developments in EDM and outlines the likely trend for future research.

The thermal characteristics of thermally treated and untreated very low density polyethylene, isotactic polypropylene and their blends were investigated. Injection moulded blends containing five different weight percentages of VLDPE/iPP were prepared and thermally treated at 100uC for 2, 4, 7 and 14 days. Differential scanning calorimetry, thermogravimetry and infrared spectral analysis techniques were used to study the effect of thermal treatment and blending ratio on the thermal and chemical stability. The addition of PE had caused the T m , heat of fusion and percentage crystallinity of PP main melting peak to decrease, indicating that both polymers are partially miscible. T m has been found to increase with aging time, however, the heat of fusion is not significantly affected. The initial and final decomposition temperatures, maximum decomposition rate temperature, order of decomposition reaction, activation energy and activation enthalpy were calculated, in a dynamic nitrogen atmosphere, and discussed in terms of blending ratios and aging times. The IR spectra of all blends at different aging times do not show any degradation products.

No abstract

Electric discharge machining (EDM) is one of the most efficient manufacturing technologies used in highly accurate processing of all electrically conductive materials irrespective of their mechanical properties. It is a non-contact thermal energy process applied to a wide range of applications, such as in the aerospace, automotive, tools, molds and dies, and surgical implements, especially for the hard-to-cut materials with simple or complex shapes and geometries. Applications to molds, tools, and dies are among the large-scale initial applications of this process. Machining these items is especially difficult as they are made of hard-to-machine materials, they have very complex shapes of high accuracy, and their surface characteristics are sensitive to machining conditions. The review of this kind with an emphasis on tool and die materials is extremely useful to relevant professions, practitioners, and researchers. This review provides an overview of the studies related to EDM with regard to selection of the process, material, and operating parameters, the effect on responses, various process variants, and new techniques adopted to enhance process performance. This paper reviews research studies on the EDM of different grades of tool steel materials. This article (i) pans out the reported literature in a modular manner with a focus on experimental and theoretical studies aimed at improving process performance, including material removal rate, surface quality, and tool wear rate, among others, (ii) examines evaluation models and techniques used to determine process conditions, and (iii) discusses the developments in EDM and outlines the trends for future research. The conclusion section of the article carves out precise highlights and gaps from each section, thus making the article easy to navigate and extremely useful to the related research community.

No abstract