Tensile Test and Corrosion Test

The aim of this coursework is “to understand the fundamentals of characterisation of engineering materials and corrosion in ferrous and non-ferrous materials”. Learning outcomes assessed by this coursework: On successful completion of this assignment students will be expected at threshold level to be able to 1. Describe the characteristics properties applications heat treatment of metals used in engineering identify these materials and explain how they are tested (LO1). 2. Describe the characteristics properties and identification of common non-metallic materials used in engineering; identify defects in these materials and explain how defects are identified treated and repaired (LO2). 3. Explain the chemical fundamentals of corrosion and state material types susceptible to corrosion. Describe and identify different types of corrosion how corrosive damage is identified and what protection is used to combat corrosive effects (LO5). Task: The students are required to perform a group task consisting of following two parts and write an individual technical report including the points specified under each test. Part-1: Tensile test Part-2: Corrosion test Military Technological College – Oman Page | 2 a. Tensile test (Part-1) – Perform tensile test on two different metallic materials i.e. ferrous and non-ferrous (Preferably Mild Steel and Aluminium) and (i) Draw stress/ strain diagrams and label the key parameters in the stress/ strain diagrams. Calculate the Young’s modulus. (ii) Compare the material properties (Young’s modulus stress-strain) of the above two metallic materials. (iii) Discuss the suitability of these materials in the discipline specific engineering applications with examples. (LO1) – Perform tensile test of one non-metallic material (Preferably Nylon or Plastic) and (i) Draw stress/ strain diagram and label the key parameters in the stress-strain diagram. Calculate the Young’s modulus. (ii) Compare the material properties (Young’s modulus stress/ strain) with the above metallic materials. (iii) Discuss the suitability of these non-metallic materials over metallic materials in discipline specific engineering applications with examples. (LO1 and LO2) – Briefly discuss case-hardening and its effects on the material in relation to tensile strength. (LO1) – Explore two advanced composite materials used in discipline specific engineering applications and briefly discuss their advantages/ disadvantages over the metallic materials. (LO1 and LO2) b. Corrosion test (Part-2) – Discuss the effects of corrosion on properties of the above same two types of metallic materials as follows. (LO1 and LO5) (i) Perform the tensile test of the above two pieces of material that have been corroded over time using a salt or an acidic solution. (NB: The students are supplied with samples which have already been corroded.) (ii) Draw the stress/ strain diagrams. Discuss how the corrosion has affected the materials’ properties by comparing the new samples performed under Part 1-Tensile test. (iii) Briefly explain the corrosion-chemical process inside the above selected solution and name any three factors which will accelerate corrosion. – Briefly discuss suitable methods which can be applied to minimise the corrosion in the discipline specific engineering applications. (LO5) Background: The tensile properties of the metallic material set the criteria for a safe design for structural applications of materials such as bridges pressure vessels ships aeroplanes and automobiles.  1. Tensile test: The tensile properties of a material are obtained by pulling a specimen of known geometry apart at a fixed rate of straining until it breaks or stretches to the machines limit. It is useful to define the load per unit area (stress) as a parameter rather than load to avoid the confusion that would arise from the fact that the load and the change in length are dependent on the cross-sectional area and original length of the specimen. The stress however changes during the test for two reasons: the load increases and the cross-sectional area decreases as the specimen gets longer. However the stress is calculated by taking the initial (original) cross-section area of the material in to avoid complications of measurements.  2. Corrosion test: Metals are frequently used in almost all walks of our present day life. Bridges railways buildings vehicles industries household articles all involve the use of metals. But we commonly observe that certain metals (except those which are least reactive like Au Pt Pd etc.) are slowly eaten up on long exposure to atmosphere. For example: a. Silver gets tarnished b. Copper develops green coating on its surface c. Iron rusts and d. Aluminium zinc lead loses its lustre. Such metals react with their environment (gases moisture) to form undesirable compounds. This process in general is referred to as corrosion of metals. Corrosion may thus be defined as the process of slow conversion of metals into their undesirable compounds (usually oxides) by reaction with moisture and other gases present in the atmosphere. Corrosion of metals is basically an oxidation-reduction process. Most metals undergo slow oxidation with atmospheric oxygen and moisture to form oxide layer on their surface. In certain metals like iron this oxide layer does not stick to the surface and gradually falls off exposing fresh metal surface to further corrosion: In this way the metal is slowly eaten away weakening the structure in which it has been used. Metals like aluminium copper chromium zinc lead react with atmospheric gases and moisture to form hydroxide oxide or trioxocarbonate (IV) layers which generally stick to their surface and their surface get tarnished. This layer however becomes a sort of protective layer which prevent further corrosion. But at higher temperatures even this layer can also crack exposing fresh surface for further corrosion. Procedure: NB: – Divide students into appropriate sub groups and employ the same group for both parts of the coursework. – Ensure that the students are adequately conversant with the operating procedures of the relevant test equipment. – Discipline specific engineering applications of the task need to be decided by the respective engineering department. The department lecturer will assist the students in the tensile testing of materials samples as specified in “Task” section of this coursework with the use of “Universal tensile testing” machine. As specified in “Task” section students are required to investigate the properties of these materials and identify the engineering structures where they might be used. Carefully record the relevant data from each experiment and compare the test data obtained from experiments in to investigate the tensile properties of each material and produce a table of results that is supported by labelled graphs showing the properties detailed above. Identify difference between the results with the help of stress/strain and/or load extension diagrams or relevant data. As per “Task” section students are further required to discuss case-hardening heat treatment process and also to explore technologically advanced composite materials used in discipline specific engineering applications. As per “Task” section students are also required to perform corrosion test for same two types of metallic materials used in tensile test. Then they are to further discuss the factors that may lead to degradation of the metal through the effects of corrosion and various methods that can be applied to minimise the risk of the metals degradation due to corrosion. You need to write a combined technical report (2000 words) for the tensile test and corrosion test in compliance with all the requirements specified in “Task” section of this course work. (Note: Do not write separate introductions conclusions and/or references for sub parts)     *** Words count = 2000 words. *** In-Text Citations and References using Harvard style. *** I’ve uploaded Excel file for Tensile Test Data. *** Attachments has been uploaded in compressed file named “Materials”.