The Best Methodology for Manufacturing a Specific Components - Lab Report Example

CES Assignment Engineering and Construction SECTION INTRODUCTION 1. Selection of Materials The selection of materials in this experiment is done through the assessment of all the materials in consideration of the desired qualities of the components produced. For example, in this experiment, the production of steel pressure vessels requires strength of the material, the durability and the weight of the materials. The production of carton is guided by the lightness of the carton to be produced. The best materials for manufacturing the pressure vessels are steel. On the other hand, the best material for producing milk carton is waste papers. The best question to ask is whether the material produces strong steel pressure vessels that can withstand the hardness testing for the mechanical behavior of materials. The other question is how the material affects the cost, performance, size and shape of the component produced. CES applies a simple and strong technique to assist in selecting the materials. 1.2. Selection of Process The selection of process, the aim is to select the best methodology for manufacturing a specific component. This is done through a systematic procedure in consideration of the target result and the safety precautions. For example, the process in this experiment was to take the measurements of the Rockwell hardness of a number of ferrous and non-ferrous metals and alloys. The selection is done through a computer-based correlation of mechanical property. The components in this experiment include pressure vessels and milk cartons. The features of a good process are the guiding principles for the choice of the process. The features include low cost, high quality of the manufactured components and utilization of minimum resources. The question to be asked in the selection of the best process is whether the process gives the strongest large steel pressure vessels at lower cost and low resource demand. The methodology used in this experiment is CES. It assists in the selection of the materials and processes in a very similar manner, with each approach relying on the ideas of the critical questions that were asked. The other possible methodology to be applied is the Rockwell testing (Budinski & Budinski 2005, p. 65). The tests for hardness are done as a direct reading a digital display or an analog dial because of the difference in the intensity of the penetration during the test cycles. SECTION 2: THE TASK The task in this experiment is to use the CES software for the selection of materials and the processes. The purpose this experiment is to take the measurement of the Rockwell hardness for a many ferrous and nonferrous samples packaged in accordance with the ASTM specifications (American Society for Testing and Materials (Ashby & Cebon 2003, p. 72). The software ought to be able in a condition that one can navigate it for every eventuality as it applies the selection process. The critical activity required is to obtain the properties of the material and run a correlation of the properties of standard mechanical features against the hardness using the CES software (Cambridge Engineering Selector) (Holman 2001, p. 71). This experiment is both achievable and valuable since the hardness provides an amount of resistance to penetration depending on the mechanical features such as tensile strength and the tensile strain capacity. 2.1. Task Definition Part 1 Navigation through Processes Figure 1: Navigation through Process Universe Figure 2: Navigation through Sub Processes The processes selected are Shaping, Casting and Machining. 2.2. Summary of the Processes 2.2.1. Shaping Shaping literally defines the physical look of the components to be manufactured. The materials selected for the shaping include aluminum, cast iron and copper. The components produced in this method have the following characteristics: Size: The size of the components equals to the amount of materials used Shape: The component is able to take any shape because of the elasticity of the materials. Dimensional Tolerance: The dimensions of the component remain the same, except in the cast iron material. Economics of the process: the process is costly because of the materials, 2.2.2. Casting Casting converts the material of the components into cast iron for strengthening. The materials selected for the shaping include cast and wrought iron and copper. The components produced in this method have the following characteristics: Size The size of the components equals to or less than the quantity of materials used Shape: The component is able to take the original shape given but cannot change later. Dimensional Tolerance: The dimensions of the component reduce due to high pressures. Economics of the process: the process is economically affordable because of reduced number of stages of the process. 2.2.3. Machining Machining implies the subjection of the materials to non- manual process to converts them into the components. The materials selected include Non-ferrous iron, aluminum and magnetic iron. The components produced in this method have the following characteristics: Size The size of the components equals the quantity of materials used Shape: The component take permanent shape determined by the machining process Dimensional Tolerance: The dimensions of the component are maintained under high pressures. Economics of the process: The process is economically expensive during the manufacture but more affordable at the maintenance stage of the process. Part 2: In-Depth Case Study of Process Selection 3.1. Manual Process Selection From the Process Universe, the processes are selected manually. This is followed by the manual selection of materials and the desired properties of the materials. Figure 3: Manual Process Selection The nest process is the plotting of the data with the selected materials and properties. All of the steps of the experiment were naturally carried out repeatedly to verify the results. The data in this selection were representative. The measurement of hardness and the averages values of the corresponding standard deviations are plotted in figure 4 below. Figure 4: Hardness Properties The hardness values of the alloys and the non-ferrous materials were found to be less than the ferrous metals, which therefore agrees with the plotted CES plots. Taking into consideration the iron and steel metals, the hardness is greater than that of cast iron, which in turn is greater than the ductile iron. The order of hardness arrangement for the materials goes consistently with the range of hardness (Gilman 1973, p. 74). A reflection on the degree of hardness, the cold steels and their alloys are harder than their hot and rolled steel. 3.2. Computer-based Correlation of Material Property The logarithmic plotting of the elastic limit of the materials against their hardness is presented in in figure 5 below. It shows strong and positive correlation between the elastic limit and the hardness. The order of hardness shows the increasing order from aluminum alloys to copper alloys then to low carbon steel then to low alloy steel (Martin & Lash 1993, p. 76). Here, the elastic limit can be defined as the greatest amount of stress, which a metal can deform elastically. However, there is a strong positive correlation between the elastic limit and the materials yield strength. This is the stress for identifying the beginning of the plastic deformation. Figure 5: CES plotting of Elastic Limit against Hardness Similarly, there is a strong positive correlation between the elastic limit and the tensile strength (ratio of the heaviest weight sustained and the area of the initial load bearing). This therefore explains the existence of an analogous correlation between the tensile strength and the hardness of materials in Figure 6 below. This specific relationship between the properties of the selected materials was critically evaluated in details owing to the dire need to get the value of the tensile strength for the selected materials. These have geometry that readily enables the testing of hardness but has a high level of inconvenience for the test of uniaxial tensile strength (Shackelford 2005, p. 221). Figure 6: CES Plotting of the Tensile Strength against Hardness Leaving aside polymers and ceramic materials the changes in hardness does not affect the increase in length (the strain capacity) in the range of values in the plotted values for a number of materials in figure 7 below. Figure 7: CES Plot of Increase in Length against Hardness However, there is a strong correlation between the Young’s modulus and hardness in figure 8 below. Figure 8: CES plot of Young’s modulus vs. Vickers hardness. 4. Overview of the Eco audit Tool in CES The data points of the discrete cylindrical correction are presented in the Rockwell hardness with values between 0 and 100 with a spacing of 10 incremental units. The eco audit tool in CES utilizes the hardness in the current experiment to develop the correlation with the elasticity and the Young’s Modulus. Additionally, the correction of the same data is accomplished through a least-squares fitting using a computer based tool such as Excel spreadsheet to get the equation of the line in the plotting of the correction factor against the Rockwell hardness (HRB). The equation applies in the manufacturing process by applying linear programming for combination of materials in the right proportions. For example, the equation relating the hardness and the correlation factor is obtained as CF = -0.05 * HRB + 6.50 for 0.5 in. On the other hand, for 0.25 in, the equation for combining materials is CF = -0.1 * HRB + 13, for a range of hardness between 10 and 90. References Ashby, M F & Cebon, D 2003, New Approaches to Materials Education for Students of Engineering, in Proceedings of the 2003 American Society for Engineering Education Annual Conference and Exposition, Session Number 2464. Budinski, K G & Budinski, M K 2005, Engineering Materials: Properties and Selection, 8th Edn., Pearson Prentice Hall, Upper Saddle River, New Jersey, p. 605. Gilman, J J 1973, Hardness–A Strength Microprobe, in The Science of Hardness Testing and Its Research Applications, American Society for Metals, pp. 51-74. Holman, J P 2001, Experimental Methods for Engineers, 7th Edn., McGraw-Hill Book Co., pp. 62-63. Martin, D H & Lash, B, 1993, Application of Hardness Testing in Foundry Processing Operations: A University and Industry Partnership, in National Educators Workshop: Update 92, NASA Conference Publication 3201, pp. 221-232. Shackelford, J F 2005, Introduction to Materials Science for Engineers, 6th Edn., Pearson Prentice Hall, Upper Saddle River, New Jersey, p. 221. Read More