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Effect of Vanadium addition to Al-Si alloy on its mechanical, tribological and microstructure properties
Available online at www.sciencedirect.com
ScienceDirect Materials Today: Proceedings 4 (2017) 307–313
www.materialstoday.com/proceedings
5th International Conference of Materials Processing and Characterization (ICMPC 2016)
Effect of Vanadium addition to Al-Si alloy on its mechanical, tribological and microstructure properties. a
Aakash Kumara,*, C. Sasikumarb
Undergraduate Student, Department of Material Science and Metallurgical Engineering, MANIT, Bhopal, MP 462007, INDIA b Assistant Professor, Department of Material Science and Metallurgical Engineering, MANIT, Bhopal, MP 462007, INDIA
Abstract The mechanical properties and tribological properties of a particular aluminium alloy is dependent on the composition and the preparation techniques. Aluminium alloys are used extensively in numerous applications like aerospace, automobile, structural etc. because of their corrosion resistance, high strength to weight ratio. Effect of Vanadium addition in Al-Si alloys on the mechanical, wear properties are investigated. Vanadium is added to the Al matrix in compositions varying from 0.05 to 0.15 wt. %. The composite is prepared using stir casting in a muffle furnace. The wettability of Vanadium in aluminium matrix is improved by the addition of K2TiF6. The specimens were prepared for the tensile, hardness and wear tests. Optical Microscope was used for microstructural analysis of the prepared specimens. The tensile strength and hardness values of the Vanadium added specimens were greater than the base Al-Si alloy. The elongation was also improved in the prepared specimens. Tribological properties were also enhanced due to the addition of Vanadium particles in Al-Si matrix. Pin on disc wear test was performed on the specimens by varying load at constant sliding velocity and then varying sliding velocity at constant load. ©2017 Elsevier Ltd. All rights reserved. Selection and peer-review under responsibility of Conference Committee Members of 5th International Conference of Materials Processing and Characterization (ICMPC 2016). Keywords:Wear, mechanical properties, vanadium, Al-Si alloy, hardness
1. Introduction The mechanical and tribological properties of aluminium alloys are dependent on the chemical composition, microstructure and the mode of manufacturing. The aluminium alloys are used extensively due to the following reasons: Light Weight, Strong and Long-lasting, Resistance to corrosion, Ductile and easily joinable. The properties are also dependent on the kinetics of solidification, composition of secondary phase compound [1]. * Corresponding author. Tel.: +91-8982449869. E-mail address: [email protected] 2214-7853©2017 Elsevier Ltd. All rights reserved. Selection and peer-review under responsibility of Conference Committee Members of 5th International Conference of Materials Processing and Characterization (ICMPC 2016).
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Clustering of additives can cause major defects and quality related problems. Vanadium, with its low diffusivity and solubility in aluminum alloys, is known to improve the high temperature strength of aluminum alloys by forming thermally stable V-containing dispersoids (Al11V) [2-3]. Several additives are added to enhance the tribological behavior of the alloy such as TiB2, SiC etc. [4]. The effects of these reinforcements enhance the mechanical as well as tribological properties of the materials. Several studies have been done on the mechanical properties and the characterization of Al alloys and its composites [5]. In the present workwe are working on the addition of Vanadium particles in Al-Si matrix and then evaluating the mechanical, tribological properties of the specimens and compare it with the base Al-Si alloys. Vanadium is added to most aluminium alloys for grain refinement just like master alloys and we are focusing on the mechanical and tribological properties of the prepared specimens [6]. Vanadium was added (0.05, 0.1, 0.15 wt. %) to Al-Si matrix. Vanadium was sieved and homogenous particles size was maintained before addition. Wettability was improved by using K2TiF6. The specimens were casted in cylindrical cast iron mould and then machined for preparation of specimens for various tests and microstructural characterization. Wear test was done on a pin on disc wear machine by varying load at constant sliding velocity and then varying sliding velocity at constant load. The analysis was done using the data procured from the test procedure. Similarly, tensile tests were performed and analyzed. Nomenclature Al-Si Aluminium Silicon Alloys UTS Ultimate Tensile strength YS Yield Strength 2. Experimental Procedures 2.1. Preparationof alloy The Vanadium particles used for addition in this present work is 99.5 % pure. The particles were sieved initially to maintain homogenous particles distribution in the matrix. The average particle size was maintained at 120 µm. The Al-Si alloy was melted in a graphite crucible and then stirring was initiated, then the Vanadium powder was added along with K2TiF6 to the molten aluminium matrix in definite composition as mentioned above. Continuous stirring was done to ensure the particles are homogenously dispersed in the Al matrix. Then the molten mix was casted in a cast iron mould. Specimens of cylindrical shape of length 120mm and diameter 14 mm were produced. Same procedure was repeated for all the other compositions of V. Finally, the casted samples were machine on the lathe for the tensile tests. Wear and hardness specimens were also prepared for the different compositions. 2.2. Testing Procedures A mechatronic UTM with 400 kN was used for tensile testing. The test temperature was maintained at 270C and the strain rate kept constant for all the experiments. A Rockwell hardness tester (model TRSND, fine manufacturing industries India) with 1/16-inch ball indenter under 100kg load were used for evaluating the hardness values. Before hardness test, specimens with diameter of 8mm were metallographically polished with a 240 grit SiC paper till the oxide layer was removed and the opposite sides were flawlessly parallel. Pin on disc machine (Model: Wear & Friction Monitor TR-20) was used for wear rate determination. Operating parameters during wear test were (i) percentage of Vanadium (ii) Normal Load (iii) Sliding velocity. The specimens and wear track were cleaned with acetone and deliberated up to accuracy of 0.0001gm. using microbalance prior to and after test. The wear rate was calculated from the height loss technique and articulated in terms of wear volume loss per unit sliding distance. 3. Results and Discussions 3.1. Mechanical properties: Figure 1 shows the stress-strain flow curve for the different specimens with varying V concentration. The curve shows that the strain induced in the 0.15 wt. % Vanadium alloy was highest. Yield Strength and Ultimate Tensile Strengthincreased with the increasing concentration of Vanadium in the matrix. The percentage elongations in all the specimen were increased showing the improvement in the ductility of the specimens.
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Fig. 1: Stress-Strain curve of specimens with varying V composition
3.2. Microstructural Properties: The microstructures of Al-Si alloys with varying concentration of V (0.05, 0.1, 0.15 wt. %) are shown in fig 2(a-c). Instead of normal metallography we used color metallography for our specimens in the microstructural analysis. So we used Weck’s reagent (4g. KMnO4, 1g. NaOH and 100ml. water) which reveals the microstructures with the help of color metallography. This reagent outlines the grain boundaries and second phase particles using different colors. The microstructure shows precipitates of Al22V2, Al2Si and Mg2Si along the grain boundaries of aluminium [7-9].
Fig.2: Microstructures of various V compositions (a) 0.05 wt. % V, (b) 0.1 wt. % V, (c) 0.15 wt. % V
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The precipitates/dispersed phases found increased with more additions of Vanadium [10]. The microstructures show the uniform distribution of Vanadium intermetallic particles in the Al-Si matrix. The intermetallic thus formed caused the mechanical properties to improve and thus strengthened the materials. The intermetallic particles are plate and globular shapes. These intermetallic particles are present along with Mg2Si and Al2Si in the matrix. The typical microstructure illustrating the precipitates of AlV intermetallic are shown in these microstructures. 3.3. Tribological properties: 3.3.1. Hardness Values: Figure 3 shown the hardness values of the various specimens with varying compositions. There is gradual increase in the hardness values as the concentration of V increases. This is due to the grain refining tendency of Vanadium particles in Al matrix. The graph shows that V addition increases the hardness value (HRC).
Fig. 3: Bar Chart showing hardness of Al-Si alloy and Al-Si-V alloy with varying compositions.
3.3.2. Wear Properties: Sliding wear loss and wear rate performance of different specimens with and without Vanadium into the matrix under dry sliding condition at ambient temperature is carried out [11-13]. Sliding distance is adjusted to 1200m and track diameter to 80m. The following results were obtained. (a) Variation of wear rate with varying load at a fix sliding velocity: Figure 4, 5, 6 shows the variation of wear rate with varying load and at different sliding velocities 1m/s, 3m/s, 5m/s respectively. Wear rate is seen to be improved as the material loss is less in vanadium added alloys. Alloy with 0.5 wt. % V shows best wear resistance at varying loads. Fig. 4.1 shows the variation of wear rate with varying load at fixed sliding velocity of 1 m/sec. The plot shows that as Vanadium is added the loss of material is less as compared to parent Al-Si alloy. Similarly, fig. 4.2 and fig. 4.3 shows the wear rate dependence on load at fixed sliding velocities 3 m/s and 5 m/s. Similar trend in the result is observed in these plots also as the wear rate retards as the Vanadium concentration increases.
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Fig. 4 Variation of wear rate of Al-Si alloy and Al-SiV alloy with load with sliding velocity 1m/s.
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Fig 5: Variation of wear rate of Al-Si alloy and Al-SiV alloy with load and sliding velocity 3m/s.
Fig 6: Variation of wear rate of Al-Si alloy and Al-Si-V alloy with load and sliding velocity 5m/s.
(b) Variation of wear rate with varying sliding velocity at a fix load: Figure 7, 8, 9 shows the variation of wear rate with varying sliding velocity and at different loads 20. 30, 50N respectively. Wear rate is seen to be improved as the material loss is less in vanadium added alloys. Alloy with 0.5 wt. % V shows best wear resistance at varying loads. Fig. 4.4 shows the variation of wear rate with sliding velocity at fixed load of 20N. The plot shows that as Vanadium is added the loss of material is less as compared to parent Al-Si alloy. Similarly, fig. 4.5 and fig. 4.6 shows the wear rate dependence on sliding velocity at fixed load of 30N and 50N. Similar trend in the result is observed in these plots also as the wear rate retards as the Vanadium concentration increases.
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Fig 7: Variation of wear rate of Al-Si alloy and Al-Si-V alloy with sliding velocity and load fix at 20N.
Fig 8: Variation of wear rate of Al-Si alloy and Al-Si-V alloy with sliding velocity and load fix at 30N.
Fig 9: Variation of wear rate of Al-Si alloy and Al-Si-V alloy with sliding velocity and load fix at 50N.
4. Conclusions The addition of Vanadium particles in Al-Si alloys resulted in the formation of intermetallic particles like Al22V2, Al2Si and Mg2Si at the grain boundaries. The vanadium addition improved the overall properties of the Al-Si alloy. The tensile strength was enhanced and the wear resistance was also improved by the addition of V. The grains were finer as compared to the as cast parent alloy. Vanadium has a tendency of grain refinement and thus property caused the improvement of the mechanical properties. The intermetallic were clearly visible in the microstructure of the AlSi-V alloy. The 0.15 wt. % addition led to the highest strength and wear resistance properties. Percentage elongation was improved in the tensile specimens which showed that the ductility was also improved as compared to the parent base Al-Si alloy. The solute drag effect of Vanadium particles in the Al matrix caused the dislocation to resist and the plastic deformation was more which led to the elongation in the specimens.
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Acknowledgements The author would like to thank the Department of Material Science and Metallurgical Engineering, MANIT Bhopal for the facilities for all the testing of the specimens and all the faculties of the department for the support and encouragement.
References [1] E.A. Starke, J.T. Staley, Progress in Aerospace Sci., 32 (1996), pp. 131–172. [2] X. Wang, F. Cong, Q. Zhu, J. Cui, Sci. China Technol. Sci., 55 (2012), pp. 510–514. [3] S. Camero, E.S. Puchi, G. Gonzalez, J. Mater. Sci., 41 (2006), pp. 7361–7373. [4] R. Keshavamurthy et al, Advanced Materials Manufacturing & Characterization Vol4 Issue 2 (2014), pp. 87-92. [5] R. S. Rana, Rajesh Purohit, V. K. Soni and S. Das, Materials Today: Proceedings 2 (2015),pp. 1149 – 1156. [6] S. Zhu, J. Yao, L. Sweet, M. Easton, J. Taylor, P. Robinson, et al. JOM, 65 (2013), pp. 584–592. [7] J.L. Murray, Journal of Phase Equilibria, 10 (1989), pp. 351–357. [8] Q. Cui, G. Itoh, M. Kanno, Y. Tsuji, K. Kobayashi, J. Jpn. Inst. Metals, 59 (1995), pp. 251–257. [9] A.K. Srivastava, S. Ranganathan, J. Mater. Res., 16 (2001), pp. 2103–2117. [10] Y.W. Kim, F.H. Froes, Mater. Sci. Eng., 98 (1988), pp. 207–211. [11] A.B. Gurcan, T.N. Baker, Wear, 188 (1995), pp. 185–191. [12] Y. Sahin, S. Murphy, J. Mater. Sci., 34 (1996), pp. 5399–5407.
[13]H.J. Lo, S. Dionne, M. Sahoo, H.M. Hawthorne, J. Mater. Sci., 27 (1992), pp. 5681–5691.
ScienceDirect Materials Today: Proceedings 4 (2017) 307–313
www.materialstoday.com/proceedings
5th International Conference of Materials Processing and Characterization (ICMPC 2016)
Effect of Vanadium addition to Al-Si alloy on its mechanical, tribological and microstructure properties. a
Aakash Kumara,*, C. Sasikumarb
Undergraduate Student, Department of Material Science and Metallurgical Engineering, MANIT, Bhopal, MP 462007, INDIA b Assistant Professor, Department of Material Science and Metallurgical Engineering, MANIT, Bhopal, MP 462007, INDIA
Abstract The mechanical properties and tribological properties of a particular aluminium alloy is dependent on the composition and the preparation techniques. Aluminium alloys are used extensively in numerous applications like aerospace, automobile, structural etc. because of their corrosion resistance, high strength to weight ratio. Effect of Vanadium addition in Al-Si alloys on the mechanical, wear properties are investigated. Vanadium is added to the Al matrix in compositions varying from 0.05 to 0.15 wt. %. The composite is prepared using stir casting in a muffle furnace. The wettability of Vanadium in aluminium matrix is improved by the addition of K2TiF6. The specimens were prepared for the tensile, hardness and wear tests. Optical Microscope was used for microstructural analysis of the prepared specimens. The tensile strength and hardness values of the Vanadium added specimens were greater than the base Al-Si alloy. The elongation was also improved in the prepared specimens. Tribological properties were also enhanced due to the addition of Vanadium particles in Al-Si matrix. Pin on disc wear test was performed on the specimens by varying load at constant sliding velocity and then varying sliding velocity at constant load. ©2017 Elsevier Ltd. All rights reserved. Selection and peer-review under responsibility of Conference Committee Members of 5th International Conference of Materials Processing and Characterization (ICMPC 2016). Keywords:Wear, mechanical properties, vanadium, Al-Si alloy, hardness
1. Introduction The mechanical and tribological properties of aluminium alloys are dependent on the chemical composition, microstructure and the mode of manufacturing. The aluminium alloys are used extensively due to the following reasons: Light Weight, Strong and Long-lasting, Resistance to corrosion, Ductile and easily joinable. The properties are also dependent on the kinetics of solidification, composition of secondary phase compound [1]. * Corresponding author. Tel.: +91-8982449869. E-mail address: [email protected] 2214-7853©2017 Elsevier Ltd. All rights reserved. Selection and peer-review under responsibility of Conference Committee Members of 5th International Conference of Materials Processing and Characterization (ICMPC 2016).
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Clustering of additives can cause major defects and quality related problems. Vanadium, with its low diffusivity and solubility in aluminum alloys, is known to improve the high temperature strength of aluminum alloys by forming thermally stable V-containing dispersoids (Al11V) [2-3]. Several additives are added to enhance the tribological behavior of the alloy such as TiB2, SiC etc. [4]. The effects of these reinforcements enhance the mechanical as well as tribological properties of the materials. Several studies have been done on the mechanical properties and the characterization of Al alloys and its composites [5]. In the present workwe are working on the addition of Vanadium particles in Al-Si matrix and then evaluating the mechanical, tribological properties of the specimens and compare it with the base Al-Si alloys. Vanadium is added to most aluminium alloys for grain refinement just like master alloys and we are focusing on the mechanical and tribological properties of the prepared specimens [6]. Vanadium was added (0.05, 0.1, 0.15 wt. %) to Al-Si matrix. Vanadium was sieved and homogenous particles size was maintained before addition. Wettability was improved by using K2TiF6. The specimens were casted in cylindrical cast iron mould and then machined for preparation of specimens for various tests and microstructural characterization. Wear test was done on a pin on disc wear machine by varying load at constant sliding velocity and then varying sliding velocity at constant load. The analysis was done using the data procured from the test procedure. Similarly, tensile tests were performed and analyzed. Nomenclature Al-Si Aluminium Silicon Alloys UTS Ultimate Tensile strength YS Yield Strength 2. Experimental Procedures 2.1. Preparationof alloy The Vanadium particles used for addition in this present work is 99.5 % pure. The particles were sieved initially to maintain homogenous particles distribution in the matrix. The average particle size was maintained at 120 µm. The Al-Si alloy was melted in a graphite crucible and then stirring was initiated, then the Vanadium powder was added along with K2TiF6 to the molten aluminium matrix in definite composition as mentioned above. Continuous stirring was done to ensure the particles are homogenously dispersed in the Al matrix. Then the molten mix was casted in a cast iron mould. Specimens of cylindrical shape of length 120mm and diameter 14 mm were produced. Same procedure was repeated for all the other compositions of V. Finally, the casted samples were machine on the lathe for the tensile tests. Wear and hardness specimens were also prepared for the different compositions. 2.2. Testing Procedures A mechatronic UTM with 400 kN was used for tensile testing. The test temperature was maintained at 270C and the strain rate kept constant for all the experiments. A Rockwell hardness tester (model TRSND, fine manufacturing industries India) with 1/16-inch ball indenter under 100kg load were used for evaluating the hardness values. Before hardness test, specimens with diameter of 8mm were metallographically polished with a 240 grit SiC paper till the oxide layer was removed and the opposite sides were flawlessly parallel. Pin on disc machine (Model: Wear & Friction Monitor TR-20) was used for wear rate determination. Operating parameters during wear test were (i) percentage of Vanadium (ii) Normal Load (iii) Sliding velocity. The specimens and wear track were cleaned with acetone and deliberated up to accuracy of 0.0001gm. using microbalance prior to and after test. The wear rate was calculated from the height loss technique and articulated in terms of wear volume loss per unit sliding distance. 3. Results and Discussions 3.1. Mechanical properties: Figure 1 shows the stress-strain flow curve for the different specimens with varying V concentration. The curve shows that the strain induced in the 0.15 wt. % Vanadium alloy was highest. Yield Strength and Ultimate Tensile Strengthincreased with the increasing concentration of Vanadium in the matrix. The percentage elongations in all the specimen were increased showing the improvement in the ductility of the specimens.
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Fig. 1: Stress-Strain curve of specimens with varying V composition
3.2. Microstructural Properties: The microstructures of Al-Si alloys with varying concentration of V (0.05, 0.1, 0.15 wt. %) are shown in fig 2(a-c). Instead of normal metallography we used color metallography for our specimens in the microstructural analysis. So we used Weck’s reagent (4g. KMnO4, 1g. NaOH and 100ml. water) which reveals the microstructures with the help of color metallography. This reagent outlines the grain boundaries and second phase particles using different colors. The microstructure shows precipitates of Al22V2, Al2Si and Mg2Si along the grain boundaries of aluminium [7-9].
Fig.2: Microstructures of various V compositions (a) 0.05 wt. % V, (b) 0.1 wt. % V, (c) 0.15 wt. % V
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The precipitates/dispersed phases found increased with more additions of Vanadium [10]. The microstructures show the uniform distribution of Vanadium intermetallic particles in the Al-Si matrix. The intermetallic thus formed caused the mechanical properties to improve and thus strengthened the materials. The intermetallic particles are plate and globular shapes. These intermetallic particles are present along with Mg2Si and Al2Si in the matrix. The typical microstructure illustrating the precipitates of AlV intermetallic are shown in these microstructures. 3.3. Tribological properties: 3.3.1. Hardness Values: Figure 3 shown the hardness values of the various specimens with varying compositions. There is gradual increase in the hardness values as the concentration of V increases. This is due to the grain refining tendency of Vanadium particles in Al matrix. The graph shows that V addition increases the hardness value (HRC).
Fig. 3: Bar Chart showing hardness of Al-Si alloy and Al-Si-V alloy with varying compositions.
3.3.2. Wear Properties: Sliding wear loss and wear rate performance of different specimens with and without Vanadium into the matrix under dry sliding condition at ambient temperature is carried out [11-13]. Sliding distance is adjusted to 1200m and track diameter to 80m. The following results were obtained. (a) Variation of wear rate with varying load at a fix sliding velocity: Figure 4, 5, 6 shows the variation of wear rate with varying load and at different sliding velocities 1m/s, 3m/s, 5m/s respectively. Wear rate is seen to be improved as the material loss is less in vanadium added alloys. Alloy with 0.5 wt. % V shows best wear resistance at varying loads. Fig. 4.1 shows the variation of wear rate with varying load at fixed sliding velocity of 1 m/sec. The plot shows that as Vanadium is added the loss of material is less as compared to parent Al-Si alloy. Similarly, fig. 4.2 and fig. 4.3 shows the wear rate dependence on load at fixed sliding velocities 3 m/s and 5 m/s. Similar trend in the result is observed in these plots also as the wear rate retards as the Vanadium concentration increases.
Aakash Kumar/ Materials Today: Proceedings 4 (2017) 307–313
Fig. 4 Variation of wear rate of Al-Si alloy and Al-SiV alloy with load with sliding velocity 1m/s.
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Fig 5: Variation of wear rate of Al-Si alloy and Al-SiV alloy with load and sliding velocity 3m/s.
Fig 6: Variation of wear rate of Al-Si alloy and Al-Si-V alloy with load and sliding velocity 5m/s.
(b) Variation of wear rate with varying sliding velocity at a fix load: Figure 7, 8, 9 shows the variation of wear rate with varying sliding velocity and at different loads 20. 30, 50N respectively. Wear rate is seen to be improved as the material loss is less in vanadium added alloys. Alloy with 0.5 wt. % V shows best wear resistance at varying loads. Fig. 4.4 shows the variation of wear rate with sliding velocity at fixed load of 20N. The plot shows that as Vanadium is added the loss of material is less as compared to parent Al-Si alloy. Similarly, fig. 4.5 and fig. 4.6 shows the wear rate dependence on sliding velocity at fixed load of 30N and 50N. Similar trend in the result is observed in these plots also as the wear rate retards as the Vanadium concentration increases.
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Fig 7: Variation of wear rate of Al-Si alloy and Al-Si-V alloy with sliding velocity and load fix at 20N.
Fig 8: Variation of wear rate of Al-Si alloy and Al-Si-V alloy with sliding velocity and load fix at 30N.
Fig 9: Variation of wear rate of Al-Si alloy and Al-Si-V alloy with sliding velocity and load fix at 50N.
4. Conclusions The addition of Vanadium particles in Al-Si alloys resulted in the formation of intermetallic particles like Al22V2, Al2Si and Mg2Si at the grain boundaries. The vanadium addition improved the overall properties of the Al-Si alloy. The tensile strength was enhanced and the wear resistance was also improved by the addition of V. The grains were finer as compared to the as cast parent alloy. Vanadium has a tendency of grain refinement and thus property caused the improvement of the mechanical properties. The intermetallic were clearly visible in the microstructure of the AlSi-V alloy. The 0.15 wt. % addition led to the highest strength and wear resistance properties. Percentage elongation was improved in the tensile specimens which showed that the ductility was also improved as compared to the parent base Al-Si alloy. The solute drag effect of Vanadium particles in the Al matrix caused the dislocation to resist and the plastic deformation was more which led to the elongation in the specimens.
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Acknowledgements The author would like to thank the Department of Material Science and Metallurgical Engineering, MANIT Bhopal for the facilities for all the testing of the specimens and all the faculties of the department for the support and encouragement.
References [1] E.A. Starke, J.T. Staley, Progress in Aerospace Sci., 32 (1996), pp. 131–172. [2] X. Wang, F. Cong, Q. Zhu, J. Cui, Sci. China Technol. Sci., 55 (2012), pp. 510–514. [3] S. Camero, E.S. Puchi, G. Gonzalez, J. Mater. Sci., 41 (2006), pp. 7361–7373. [4] R. Keshavamurthy et al, Advanced Materials Manufacturing & Characterization Vol4 Issue 2 (2014), pp. 87-92. [5] R. S. Rana, Rajesh Purohit, V. K. Soni and S. Das, Materials Today: Proceedings 2 (2015),pp. 1149 – 1156. [6] S. Zhu, J. Yao, L. Sweet, M. Easton, J. Taylor, P. Robinson, et al. JOM, 65 (2013), pp. 584–592. [7] J.L. Murray, Journal of Phase Equilibria, 10 (1989), pp. 351–357. [8] Q. Cui, G. Itoh, M. Kanno, Y. Tsuji, K. Kobayashi, J. Jpn. Inst. Metals, 59 (1995), pp. 251–257. [9] A.K. Srivastava, S. Ranganathan, J. Mater. Res., 16 (2001), pp. 2103–2117. [10] Y.W. Kim, F.H. Froes, Mater. Sci. Eng., 98 (1988), pp. 207–211. [11] A.B. Gurcan, T.N. Baker, Wear, 188 (1995), pp. 185–191. [12] Y. Sahin, S. Murphy, J. Mater. Sci., 34 (1996), pp. 5399–5407.
[13]H.J. Lo, S. Dionne, M. Sahoo, H.M. Hawthorne, J. Mater. Sci., 27 (1992), pp. 5681–5691.