An evaluation of the production of magnesium base alloy castings by the expendable pattern casting process

Magnesium alloy is a light weight metallic material which offers good engineering properties and environmental advantages. Most cast components in this material are produced by the traditional casting processes, predominantly the die-casting process. The Expendable Pattern Casting Process (EPC process) is a relatively new casting process which provides many design, processing and environmental benefits. However, the process differs significantly from the conventional empty mould sand casting process and there is the need for research to develop an understanding of the process parameters. The research was established to provide a preliminary evaluation of the production of magnesium base alloy castings by the expendable pattern casting process under gravity and counter gravity pouring. The major process parameters investigated were filling pressure, pouring temperature and pattern bead density. The problems experienced in applying this process for this material in the experimental research were defined. Microstructures and mechanical properties of the cast specimens were investigated and reported. The results showed that the quality of test bar specimens produced by the EPC process under counter gravity pouring with optimised process parameters was compatible with the quality of castings produced by the conventional sand casting process. In addition to the experimental research a review was conducted of the modelling of different methods of pouring. The pouring methods considered were bottom gating in gravity pouring, counter gravity pouring in an empty cavity mould process, and expendable pattern casting processes under both gravity and counter gravity pouring. A quasi one dimensional fluid mechanics analysis was conducted to explain the effect of pattern degradation on the delay in mould filling

New Methods for ferrous raw materials characterization in electric steelmaking

425 p.In the siderurgical sector, the steel scrap is the most important raw material in electric steelmaking,contributing between 70% of the total production costs. It is well-known how the degree of which thescrap mix can be optimized, and also the degree of which the melting operation can be controlled andautomated, is limited by the knowledge of the properties of the scrap and other raw-materials in thecharge mix.Therefore, it is of strategic importance having accurate information about the scrap composition of thedifferent steel scrap types. In other words, knowing scrap characteristics is a key point in order to managethe steel-shop resources, optimize the scrap charge mix/composition at the electric arc furnace (EAF),increase the plant productivity, minimize the environmental footprint of steelmaking activities and tohave the lowest total cost of ownership of the plant.As a main objective of present doctoral thesis, the doctorate will provide new tools and methods of scrapcharacterization to increase the current recycling ration, through better knowledge of the quality of thescrap, and thus go in the direction of a 100% recycling ratio. In order to achieve it, two main workinglines were developed in present research. Firstly, it was analysed not only the different existingmethodologies for scrap characterization and EAF process optimization, but also to develop new methodsor combination of existing, Secondly, it was defined a general recommendations guide for implementingthese methods based on the specifics of each plant

Gas, Water and Solid Waste Treatment Technology

This book introduces a variety of treatment technologies, such as physical, chemical, and biological methods for the treatment of gas emissions, wastewater, and solid waste. It provides a useful source of information for engineers and specialists, as well as for undergraduate and postgraduate students, in the areas of environmental science and engineering