Materials Science Lab Report:
Abstract: In this Materials Science lab, we performed the Metallography Experiment. It included preparing and examining a metallographic sample or steel specimen in a rigid step-by-step process. This procedure consisted of sectioning, mounting, course and fine grinding, polishing, etching, and viewing the specimen through the microscope (Metallography experiment pdf). Great care and precision must be taken when dealing with the specimen or else a change in its original microstructure may occur and hence, inaccurate results may be obtained. The results of our experiment included finding the values of N and n, where N denotes the number of grains per square inch at a magnifying factor of 400X and n represents the ASTM grain size number. These numbers enable us to study the properties of the given material. Thus, we have found them to be: N=
0.674 grain/inch2
; n= 6.201
Consequently, we came to a conclusion that this material exhibits the following characteristics:
Introduction: There comes a time when materials engineers are called upon to create new products. In order to accomplish that, they must develop a comprehensive knowledge of the materials and their properties. Hence, materials engineers with a firm background must be able to predict the behavior and performance of materials only by examining their microstructure, the small scaled structure (2016). As a result, the science of metallography, or materialography, has been developed within the last fifteen years due to its importance in closely investigating and testing the microstructure of the materials. The founder of metallography is known as Henry Clifton Sorby whom happens to also be a geologist, petrographer, and mineralogist.
Clearly stated, metallography is the science interested in the study of the microscopic composition of metals and metal alloys. It reveals the atomic and chemical structure of elements in metals and alloys. The objectives of this experiment were to learn the techniques of specimen, a sample of a material, preparation in metallography. As well as, an analysis and a study regarding that metal specimen microstructure was to be made. Preparation of specimens requires five major operations. This experiment starts off with the selection of a suitable specimen which is obtained from the
original material by the abrasive cutting machine. For safety insurance and because the specimen’s size is small, the specimen is inserted into the Specimen Mounting Press to support it with plastic mould. Moving on, a grinder is used to remove any surface imperfections followed by utilizing a polisher that clears away any scratches off the specimen’s surface that may affect our results. Finally, we arrive at the most significant stage that is known as the etching stage; this is the stage where the structure of the specimen and the boundaries of its grains, group of atoms, are revealed visibly through a microscope. As soon as its microscopic organization is known, structural characteristics such as grain size, number, and shape are identified (2016). Subsequently, these characteristics will eventually affect the mechanical and physical properties of the material. Once all the constitutional properties of the material are known, one can make good use of the material and use it in suitable situations. The importance of metallography is that it supplies us with efficient knowledge to guess the type of material we are dealing with by viewing its macroscopic structure. Moreover, it enables us to determine its physical properties by using an optical or electron microscopy ("CONCLUSION Metallography is one of the most important part of - MATH - 265", 2016). An optical microscope is one in which it directs an intense light on the specimen’s surface in order to get the magnified image of the specimen; this image consists of small grains that influence the various properties of the material. As well as, observation of defects that are on the finished products but cannot be viewed through the naked eye can be spotted by metallography. In brief, (2016) stated that “Metallography is the study of the structural characteristics or constitution of a metal or an alloy in relation to its physical and mechanical properties;” on top of that, the most important section of metallography that helps in evaluating those properties is viewing the metal specimen through a microscope. Metallographic examination provides us with quantitative information regarding the specimen grain sizes, the amount of interfacial area per unit volume, and other useful properties. Viewing the specimen with a microscope will help us determine the possibility for this material to be used for a specific purpose.
References:
(2016). Retrieved 20 September 2016, from http://www.csun.edu/~bavarian/Courses/MSE%20227/Labs/3Metallography.pdf Metallography experiment pdf from Blackboard. CONCLUSION Metallography is one of the most important part of - MATH 265. (2016). Coursehero.com. Retrieved 20 September 2016, from https://www.coursehero.com/file/p5h7r19/CONCLUSION-Metallography-is-oneof-the-most-important-part-of-physical/
