Essays on Solidification

Question #1: Graphical illustration of energy changes during the formation of the nucleus in homogeneous solidification phenomenon.

The solidification phenomenon of a metal starts with the formation of nuclei in a liquid melt, the nuclei forms a stable nuclei in the same melt, and finally formation of the solidified structure of grained crystals. The structure is illustrated in the following diagrams. Figure 1. Solidification process

Question #2: Comparison between homogeneous and heterogeneous nucleation

In the homogenous nucleation, the nuclei are synthesized from metal solidifying atoms. In heterogeneous nucleation, the nucleating agents are the impurity atoms as well as the container surfaces

Question #3: Production of large silicon single crystals

The large silicon single crystals are generated by the use of pure silicon seed crystals in a silicon melt in the Czochralski process.

Question #4: What are a metal alloy and solid solution?

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Introduction

Waste is generated as a result of a lot of physical, chemical, and biological processes. Dumping it at some appropriate place is one option. However, ecological effects of throwing away waste products are becoming a serious concern these days. In order to minimize waste, the best strategy is to transform it into valuable products . Plenty of research studies have been carried out to utilize waste effectively. The aim of this report is analysis of the proposed methods for the utilization of common forms of wastes for useful purposes. We also recommend better alternatives to help create a lesser negative ...

For a casting process to be successful, various variables will need to be controlled. These variables will range from the characteristics of the metals, or the alloys, the specific method of casting, the molten metal materials and design and other process parameters. Others like the flow of the molten metal in the cavities, the gating systems, the gases evolved, and the cooling rate of the molten metals will influence its quality. This paper is going to discuss the design consideration in casting, the selection of the material processes, selection of the casting process, inspection and problems in casting and ...