ENG1051 Materials for Energy and Sustainability Sem 2 2021 Corrosion Practical/Questions (5%) Due date: Tuesday 21 September at 11.55pm Melbourne Time. Submission box on Moodle. Please use typed answers using 2 cm margins, 12 pt font and single line spacing for all questions. Referencing: American Institute of Physics (AIP) style Start each question on a new page. This is an INDIVIDUAL assignment 1. Galvanic corrosion and the effect of oxygen – copper and galvanized steel. Maximum 2 pages excluding references. i) Why was it important to remove the air bubble ii) Sketch the electrochemical cell, indicating the ANODE, CATHODE, and direction of flow of electrons. Mark on your diagram the electrode at which metal is being corroded and the electrode at which reduction is taking place. iii) On a single graph, make plots of current vs time, for 1.2, 1.4 and 1.5 in the lab manual. Set the time to t=0 at the start of each plot. There will be 5 plots in total on the single graph. iv) Provide a brief explanation for changes (if any) in current in your plots of current vs time. v) Determine the thinning rate of the anode as instructed in 1.3. Show your calculations. 2. Anode/Cathode Surface Area – copper and mild steel. Maximum 2 pages excluding references. i) Sketch the electrochemical cell, indicating the ANODE, CATHODE, and direction of flow of electrons. Mark on your diagram the electrode being corroded and the electrode at which reduction is taking place. ii) Compare the current flow of the copper/steel couple with the copper/galvanized steel performed previously and briefly discuss the differences according to their relative positions in the Galvanic series. iii) Discuss the relationship between ANODE/CATHODE surface area, current density and the rate of corrosion. iv) Using the above information, discuss why coating steel sheet with zinc ie. galvanizing effectively protects the steel from corrosion even when there is scratch exposing the steel. ENG1051 Materials for Energy and Sustainability Sem 2 2021 3. Corrosion Case Study. Maximum 4 pages excluding references. Your task is to find a metal component or structure that is corroding. This must be something at your place of residence. Due to COVID lockdown restrictions and importantly for your well-being, do NOT start looking for a corroding component/structure away from your residence. If you cannot find something that is corroding at your place of residence, please contact john.forsythe@monash.edu who will provide you with an example. Do NOT find an example on the internet. Once you have selected your corrosion case study, answer each of the questions below – you MUST use the same questions numbers below to allow ease of marking. i) Describe the corroding structure/component – its state and condition, with the help of a photograph (a photograph is required in your report). Is it located outdoors or indoors ii) What is the function of the structure/component iii) Describe the immediate environment of the structure/component. iv) Using Granta CES Edupack, make a suggestion of the metal/alloy that is corroding. v) Discuss why the metal/alloy was selected for this particular application. vi) Suggest a possible processing method used in the manufacture of the component/ structure. vii) Using knowledge gained from the course, discuss the possible types of corrosion processes and explain the reasons for your assessment. Explain why multiple mechanisms (and not single forms) of corrosion generally occur in practice. viii) Draw a picture to help illustrate the multiple corrosion processes taking place. ix) In your opinion, was corrosion taken into consideration in the design of and material selection for the structure/component Explain your reasons. x) What type of corrosion prevention system was initially implemented and why is it failing
