Engineering Properties of Various Engineering Materials - Lab Report Example

ENGINEERING MATERIALS By I. Executive summary The experiment was based on the study of engineering properties of various engineering materials. It was performed to determine the general characteristics of different engineering materials. The material used in the experiment included carbon steel, HPDE, Polycarbonate, polypropylene, PVC, nylon, polystyrene and aluminum. A mechanical testing machine was used in the experiment. The experiments were done to gain first-hand information on the reaction of these materials. A review of the respective stress vs. strain graphs were applied to easily compute the tensile strength of the material Tests were done using different materials to come up with the experiment’s objective. All the required data were collected and recorded in a table to enable calculation. The calculations are really based on accepted formulas. The calculated value includes the impact energy and the impact resistance. Generally, the property of all the materials was achieved. the reactions of the material specimens under various conditions was done .The materials’ reactions helped in deriving the significant information regarding the structural and mechanical composition of the specimens. The experiment really helped in identifying and determining various mechanical properties is of the materials that were under consideration. II. Background Statement: Having and understanding the properties of various engineering materials is really an important factor to Civil Engineers .In Most Engineering jobs, materials such as carbon steel, HPDE, Polycarbonate, polypropylene, PVC, nylon, polystyrene and aluminum are commonly used for various design and engineering work. Carbon steel is usually a tough metal with high carbon steel having carbon contents of between 0.55% to1.5 percent. This percentage normally gives the reason why it is always tougher and able to withstand both shocks and even vibrations. The high Carbon steel is usually used by engineers to make tools such as the drills, chisels and files. Polycarbonate is also an important material to consider, its main material is usually produced by the reaction that occurs between bisphenol A (BPA) and the phosgene COCl. This material on its nature can easily be moulded and are usually used by engineers to various items like bicycle helmets, microwave cookware and even the bullet proof windows are made from it. Generally, Most of the today’s thermoplastics are categorized into two categories. That is the amorphous and the crystalline which are however very difficult. All these plastic materials and the aluminum metal constitutes important material that engineers need to know their properties as they are used greatly in engineering III. Objective The main objective of this lab experiment was to study the engineering properties of various engineering materials. Samples were taken from different materials. This included carbon steel, HPDE, Polycarbonate, polypropylene, PVC, nylon, polystyrene and aluminum. These materials were tested for strength properties using a mechanical testing machine. These experiments were done to gain a first-hand experience the natures of that are largely empirical. A review of the respective stress vs. strain graphs can easily compute the tensile strength of the material. IV. Experimental Methods: Using various mechanical testing machines, tests were performed on sections of specimen of each material. The tests were being done alternately using different mechanical machines as mentioned above. The property of this materials were being evaluated on the basis of their Impact energy , Impact resistance , Type of test and the work contents.The width, thickness and cross section of each material was also taken before the tests. Zwick/Roell Pendulum Impact Tester was used for the tests. The Impact tests are usually short-term tests which gives information on the behavioral failure of given materials given varying temperatures. At the end of each test, the outcome (results) of each material were observed and recorded in the laboratory. For analysis purposes all the properties of individual material was clearly recorded in a table. The numerical data was sent to a computer as a raw data and graphs file for further review. The graphs were generated from the table’s calculated records. The graphs are plotted in work (j) against the specimen number and stress in N/mm3 against strain in percentage for all the materials, that is Material: HDPE ,Material: (PP.) Polypropylene ,Material: PVC ,Material: Polycarbonate and Material: Nylon V. Results Zwick/Roell Pendulum Impact Tester . Sunday, 11 September 2016 M/c Model No 5113. Ref No A466690. Force 7.5J Material: HDPE TABLE 1 Specimen width b0 Specimen thickness a0 Cross-section Impact energy Impact energy Impact resistance Type of test, PIT Work contents Material Legends Nr mm mm mm² J % kJ/m² J “ 1 14.96 3.03 45.33 1.64 21.82 36.10 Charpy 7.50 “ 2 14.97 3.1 46.41 0.48 6.35 10.26 Charpy 7.50 “ 3 14.69 2.78 40.84 0.65 8.61 15.81 Charpy 7.50 “ 4 15.28 2.99 45.69 0.64 8.54 14.02 Charpy 7.50 Failure type 1-4= Hinged From the table above showing the recorded data for HDPE test, each specimen’s width was taken in mm,The same case was for the specimen’s thickness(also recorded in mm).The cross-section measurements were too taken from each specimen and recorded in mm² The impact energy was recorded both in joules (j) and percentages (computed from the energy in joules) The impact resistance was recorded in kilojoules per metre squared (kJ/m²). As recorded, all the specimens were using the Charpy ,PIT test type. The work contents was a constant of 7.50 joules The graph above was achieved from the data recorded in table 1.The specimen number on the X axis was plotted against energy in joules on the Y axis. Both the impact energy and resistance energy behavior was shown from the graph Table 2 Hardness of carbon steels (load 20Kg) 1st measurement 2nd measurement 3rd measurement 0.1% Carbon 146 143 151 0.2% Carbon 169 161 171 0.4% Carbon 206 211 219 0.85% Carbon 254 260 256 Table 2 shows different carbon percentages computed under different measurements. It can be observed from the table that same percentage of carbon produces independent figures under different measurement. For instance, 0.1% Carbon from the 1st measurement has a figure of 146 different from the figure in the 2nd measurement which is 143 and also not the same as the 3rd measurement of 151 Zwick/Roell Pendulum Impact Tester . Sunday, 11 September 2016 M/c Model No 5113. Ref No A466690. Force 7.5J Material: (PP.) Polypropylene Table 3 Specimen width b0 Specimen thickness a0 Cross-section Impact energy Impact energy Impact resistance Type of test, PIT Work contents Material Legends Nr mm mm mm² J % kJ/m² J PP “ 1 15.95 3.1 49.45 1.30 17.33 26.29 Charpy 7.50 “ 2 14.91 3.3 49.2 1.21 16.13 24.59 Charpy 7.50 “ 3 15.93 3.43 54.64 1.12 14.87 20.41 Charpy 7.50 “ 4 15.3 3.5 53.55 1.36 18.11 25.36 Charpy 7.50 “ 5 3.06 15.9 48.65 5.89 78.54 121.07 Charpy 7.50 Failure type= 1-4 Hinged , 5 specimen was flat & brittle. Just as table one which was based on HDPE as the test material, for each specimen on the Polypropylene test ,width and thickness were taken in mm,The same case was for the specimen’s thickness(also recorded in mm).The cross-section measurements were too taken from each specimen and recorded in mm² Also The impact energy was recorded both in joules (j) and percentages (computed from the energy in joules) The impact resistance was recorded in kilojoules per metre squared (kJ/m²). As recorded, all the specimens were using the Charpy ,PIT test type. The work contents was a constant of 7.50 joules Figure 2 The graph above was achieved from the data recorded in table 2.The specimen number on the X axis was plotted against energy in joules on the Y axis. Both the impact energy and resistance energy behavior was shown from the graph. Compared to the graph plotted from data in table one, it is evident that the behavior of the reactions showing the impact energy and the resistance energy is different. More of reactions are seen in the figure . Zwick/Roell Pendulum Impact Tester . Sunday, 11 September 2016 M/c Model No 5113. Ref No A466690. Force 7.5J Material: PVC Table 4 Specimen width b0 Specimen thickness a0 Cross-section Impact energy Impact energy Impact resistance Type of test, PIT Work contents Material Legends Nr mm mm mm² J % kJ/m² J “ 1 15.76 3 47.28 0.37 4.88 7.74 Charpy 7.50 “ 2 14.85 2.81 41.73 0.37 4.88 8.77 Charpy 7.50 “ 3 15.12 2.92 44.15 0.34 4.47 7.59 Charpy 7.50 “ 4 15.76 2.77 43.66 0.26 3.46 5.94 Charpy 7.50 Failure type 1-4= Brittle Same here, each specimen’s width and thickness was taken in mm and the cross-section measurements recorded in mm² The impact energy recorded both in joules (j) and percentages (computed from the energy in joules) the impact resistance was recorded in kilojoules per metre squared (kJ/m²). As recorded, all the specimens were using the Charpy ,PIT test type. The work contents was a constant of 7.50 joules Figure 3 The graph here shows a less reactive process as compared to the prcess in figure Zwick/Roell Pendulum Impact Tester . Sunday, 11 September 2016 M/c Model No 5113. Ref No A466690. Force 7.5J Material: Polycarbonate Specimen width b0 Specimen thickness a0 Cross-section Impact energy Impact energy Impact resistance Type of test, PIT Work contents Material Legends Nr mm mm mm² J % kJ/m² J “ 1 15.36 3.04 46.69 2.71 36.09 57.97 Charpy 7.50 “ 2 15.5 3.07 47.59 2.83 37.67 59.37 Charpy 7.50 “ 3 16.12 3.04 49 2.57 34.31 52.51 Charpy 7.50 “ 4 15.4 3.02 46.51 2.57 34.21 55.17 Charpy 7.50 “ 5 15.9 2.98 47.38 5.25 70.02 110.83 Charpy 7.50 Failure type 1-4= Hinged Zwick/Roell Pendulum Impact Tester . Sunday, 11 September 2016 M/c Model No 5113. Ref No A466690. Force 7.5J Material: Nylon Specimen width b0 Specimen thickness a0 Cross-section Impact energy Impact energy Impact resistance Type of test, PIT Work contents Material Legends Nr mm mm mm² J % kJ/m² J “ 1 14.87 3.24 48.18 4.54 60.47 94.13 Charpy 7.50 “ 2 15.31 3.24 49.6 4.85 64.62 97.70 Charpy 7.50 “ 3 16.02 3.19 51.1 2.48 33.07 48.53 Charpy 7.50 “ 4 13.7 3.2 43.84 3.35 44.62 76.33 Charpy 7.50 “ 5 14.36 3.18 45.66 3.59 47.86 78.61 Charpy 7.50 “ 6 13.6 3.02 41.07 2.64 35.14 64.17 Charpy 7.50 Un-Notched Failure type 1-2= Bent, 3-5= Brittle, 6=Bent NOTE: the same processes and procedures were done to achieve the above shown table and graphs 4ET002 Nylon PA66 and PA66 40%GF (glass fibre reinforced) 1. 50 mm/min, 2. 500 mm/min, 3. PA66GF40 50 mm/min; Secant points 15 and 25 MPa but for PA66GF40 30 and 60 MPa. Specimen width b0 Specimen thickness a0 S0 Rp 0.2 E-Modulus RB W up to Fmax. W up to break Rm  Fmax.  Break Nr mm mm mm² MPa MPa MPa J J MPa % % 1 10.21 3.2 32.67 28.99 959.14 44.60 18.40 163.37 49.47 26.67 215.18 2 9.9 3.28 32.47 29.19 961.85 41.28 18.32 56.21 51.08 26.61 75.99 3 12.7 3.26 41.4 104.60 6801.18 131.12 7.06 8.03 136.99 3.57 3.91 F max Fmax dL at F max F Break dL at break Nr MPa MPa % MPa % 1 410.10 410.10 2.1 98.8 3.5 2 537.64 537.64 1.8 141 2.8 3 683.62 683.62 1.7 191 2.8 4 768.67 768.67 1.6 269 2.2 5 1082.99 1082.99 0.9 398 1.2 4ET002 HDPE 1. 500 mm/min, 2-3. 50 mm/min; secant points 10 and 14 MPa. Specimen width b0 Specimen thickness a0 S0 Rp 0.2 E-Modulus RB W up to Fmax. W up to break Rm  Fmax.  Break Nr mm mm mm² MPa MPa MPa J J MPa % % 1 9.97 4.06 40.46 18.45 1108.34 14.04 4.41 11.47 28.18 9.08 21.59 2 9.97 4.05 40.38 17.23 1534.63* 12.82 4.17 23.07 25.65 9.58 55.14+ 3 9.95 3.96 39.4 17.14 798.00 7.95 4.37 104.67 25.84 10.15 376.72 *discard this result 4ET002 Polystyrene (PS) and Toughened PS Both 50 mm/min, Secant points 25 and 35 MPa for PS (1) but for TPS (2) 10 and 18 MPa. Specimen width b0 Specimen thickness a0 S0 Rp 0.2 E-Modulus RB W up to Fmax. W up to break Rm  Fmax.  Break Nr mm mm mm² MPa MPa MPa J J MPa % % 1 10.18 4.04 41.94 41.71 3117.21 41.35 0.54 0.78 41.87 0.98 1.26 2 10.18 4.04 41.13 25.47 1596.01 15.03 0.50 19.15 25.52 1.28 53.09 4ET002 PVC 1. 50 mm/min, 2-3. 500 mm/min, 4. 5 mm/min; Secant points 15 and 25 MPa Specimen width b0 Specimen thickness a0 S0 Rp 0.2 E-Modulus RB W up to Fmax. W up to break Rm  Fmax.  Break Nr mm mm mm² MPa MPa MPa J J MPa % % 1 10.3 2.95 30.39 46.44 2933.84 28.49 2.09 15.52 58.44 3.41 24.32 2 10.1 2.97 30 47.59 2933.84 34.78 2.24 14.02 61.49 3.53 20.03 3 10.26 3 30.81 49.90 2808.03 31.58 2.31 14.57 62.09 3.29 20.37 4 10.26 3 30.78 41.22 3117.21 7.10 1.72 4.86 53.94 2.85 6.34* *untypical – should be highest  Break The red line colour in the graphs represents the Aluminium, Green represents Al.Alloy HE15 Naturally Aged,Blue represents the H.C Copper Hard Drawn and finally Orange to represent the 70/30 Brass Hard Drawn.From the graphs, it can be seen that different materials react different as shown from the graphs Just below is the summary key for the graphs Red Aluminium Green Al. Alloy HE15 Naturally Aged Blue H.C. Copper Hard Drawn Orange 70/30 Brass Hard Drawn It is also important to note that the graphs are plotted with the strain percentage on the X axis and the stress in N/mm2 From the above tables and graphs showing the strain in percentages, the data recorded in the table shows the specimen width in mm,specimen thickness in mm,SO in mm², the RP,RB, E-modules(MPa) ,W up Fmax ,W up to break both in joules,Rm (MPa), Fmax and the Break both having calculated percentages Also below are the relevant data which is related to the experiment Fmax Fmax dL at Fmax FBreak dL at break Nr N/mm² N mm N mm 1 72.46 1451.37 5.8 145 12.6 2 464.03 9294.36 2.9 3100 4.1 3 418.88 8390.03 6.9 2060 10.2 4 363.02 7271.18 1.2 1020 4.0 dL = Strain (Ashby & Jones 2012; Henkel & Pense 2002; Budinski & Budinski 2010; Higgins 1977; Sharma 2005) V .Conclusion The experiment clearly demonstrate on the laboratory experiment that helps determine the properties of different materials .The main aim of the experiment was achieved as the recorded data with the help of the clearly drawn graphs shows clearly the reactions of different materials and from this, one could be able to determine their property .The objective of this lab was to examine the mechanical properties of various materials engineering used in engineering. A study of the reactions of the material specimens under various conditions can be used to derive significant information regarding their structural and mechanical composition. This lab assisted us as engineers to identify how certain mechanical properties are realized. During the Laboratory session, the process of collecting both the impact energy and the impact resistance that were needed for each specimen occurred in the most highly efficient manner. To achieve quicker and accurate results, the lab needed to have more equipment availed during the lab experiment period. Reference List Ashby, M. F., & Jones, D. R. H. (2012). Engineering materials. 1, 1. Amsterdam, Boston. Budinski, K. G., & Budinski, M. K. (2010). Engineering materials: properties and selection. Upper Saddle River, N.J., Prentice Hall. Henkel, D. P., & Pense, A. W. (2002). Structure and properties of engineering materials. Boston, Mass. [u.a.], McGraw-Hill. Higgins, R. A. (1997). The properties of engineering materials. London: Hodder and Stoughton. Sharma, C. P. (2005). Engineering materials: properties and applications of metals and alloys. New Delhi, Prentice-Hall of India. Read More