TAP WATER EFFECT ON SOME MECHANICAL

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1 International Journal of Mechanical Engineering and Technology (IJMET) Volume 8, Issue 3, March 2017, pp Article ID: IJMET_08_03_040 Available online at aeme.com/ijmet/issues.asp?jtype=ijmet&vtyp pe=8&itype=3 ISSN Print: and ISSN Online: IAEME Publication Scopus Indexed TAP WATER EFFECT ON SOME OF MECHANICAL PROPERTIES OF ALUMINUM ALLOYS ABDUL KHALIQ A. HASAN Mechanical Department / Technical Institute of Basrah Southern Technical University - Iraq ABSTRACT This work is aimed to measured the Corrosion Rate and the hardness of aluminum alloy affected by a tap water stream. The Aluminum specimen used was heat treated at (500ºC) for(1 hr) then cooled rapidly at the room temperature.the specimen was exposed to a stream of tap water, the speed of the water stream was (3.2 m/ sec ). This repeated at different periods of time ( from 0.5 to 15 hrs ) using a system that consist of two basins of water, each one ( 50*50*35 ) cm ³ size. The specimen fixed in the upper basin. The stream of tap water located at 2.5 cm from the specimen. Then measure the weight loss of the specimen due to the effect of corrosion of the water. The Weight Loss per unit area, the Corrosion Rate, and the relation between each of them to exposed time, was calculated. Also the values of the hardness of the specimen after each time was calculated. The results show thatt Weight Loss per unit area increase at the first hours of exposure time to the water ( till 3 hrs ), then becomes constant at the remaining time, the Corrosion Rate was maximum after ( 0.5 hr) then decrease gradually, and turned to low rate after more than 10 hrs of exposed time,the hardness increased with the increase of exposed time to the water. Key Words: Tap Water ; Aluminum Alloys ; Mechanical Properties Cite this Article: Abdul Khaliq A. Hasan, Tap Water Effect on Some of Mechanical Properties of Aluminum Alloys, International Journal of Mechanical Engineering and Technology, 8(3), 2017, pp IType=3 1. INTRODUCTION The Two classes of Aluminumm alloys are Wrought alloys & Cast alloys. Wrought alloys or mechanically worked produced by rolling, extrusion, drawing and forging, which are subdivided into two types: Heat treatable and non heat treatable alloys[1]. Aluminum alloy contains elements like (Fe, Mn, Zn, Cu,) to improve their mechanical properties, [2 ]Aluminum alloy is very active when exposed to a source of oxygen, it reacts to form a thin editor@iaeme.com

2 Tap Water Effect on Some of Mechanical Properties of Aluminum Alloys transparent oxide film over the whole of the exposed alloy surface. This film controls the rate of corrosion and protects the substrate metal allowing the production of long life components in aluminum alloys. If the film is damaged and cannot be repaired, corrosion rate of the substrate occurs very rapidly [3],[4].The corrosion resistance of Aluminum and its alloys is depend upon a protective oxide film, which is naturally self renewing and accidental abrasion or other mechanical damage of the surface film is rapidly repaired [5]. Amjad [6] studied the effect of graphite on corrosion rate of Al-Si alloy by using river,tap, and sea water. He showed that corrosion rate in the river water is less than that in the tap and sea water. Maksimovic [7] studied the effect of small additions of Si and Ge on the hardness of commercial Al-Cu alloy.he found that for the same level of micro alloying in alloy Al-Cu- Si-Ge, a maximum hardness was achieved three times faster than in alloy Al-Cu, the accelerated precipitation kinetics is a consequence of the presence of fine Si and Ge particles, serving as heterogeneous precipitation sites for strengthening particles. Ohmori [8] studied the effect of increasing Si content on the (Al-Mg-Si alloys) on the mechanical properties and aging behavior of(al-mg-si) alloy. Tony Anderson [9] studied the effect of alloying elements on the pure aluminum and influence on the mechanical properties. H.Snelson Engineers [10] study the effect of sea water on the loss in weight in the aluminum sheets and compare with other metals, and found that the average for the deepest corrosion on aluminum sheets was 0.07 mm after 8 years, and the loss in weight become 7 g / m ². Al-Mtori [11] studied the effect of Zr & Te elements to (Al-Cu) and (Al-Zn) alloys on erosion corrosion behavior, he found that the erosion-corrosion rate of (Al-Zn) alloys is less than(al-cu) alloy. Kwon [12] studied the effect of Cu & Ni particles on Al-Si alloy, he showed an increase in ultimate tensile strength & hardness. Abtehal [13] studied the erosion behavior of Al-Li alloy, she found that the erosion rate of the (Al-Li) alloy is increased. 2. MECHANICAL PROPERTIES The mechanical properties represent the most important information to understand the properties of the materials. Generally dealing with materials requiring information about their mechanical behavior and how this behavior can be measured by mechanical tests. One of this properties is the Hardness, which consider as one of the important mechanical properties, which represent as the resistance of metal to penetration of the other materials or resistance of metal to the crash [19]. 2.1 Vickers Hardness There are many process to determine the hardness, one of these process is : Vickers. Vickers Hardness ( Hv ) = ( * p ) / d² ( Kg / mm² ) (1) Where : d = diameter of penetration ( mm) p = load ( Kg ) 2.2. Heat Treatment The "Heat Treatment" for aluminum alloys is frequently restricted to the specific process employed to increase the strength and the hardness for wrought and cast alloys. These are usually referred to heating and cooling[14]. Heat treatment employed to increase the strength of Aluminum alloys and be classified as : Homogenizing heat treatment, Solution heat treatment and Quenching [15] editor@iaeme.com

3 Abdul Khaliq A. Hasan 2.3 Homogenization This treatment used to eliminate solute concentration gradient in the super cooled as cast matrix and to take into solid solution. It is a high temperature treatment. As many as possible of the crystals and intermetallics formed or precipitated at grain boundaries. Due to evolve rapidly towards the state of thermodynamic equilibrium, without eliminating all surviving effects of the casting process, and to relieve internal casting stresses [16]. 2.4 Solution Heat Treatment This treatment in aluminum alloys obtain the maximum concentration of the hardening solute such as Zn, Si, Mg and Cu in solution by heating the alloy to a temperature in which a single phase will be created. This heat treatments effect solid solution of alloying constituents and improve mechanical properties [1],[17]. 2.5 Corrosion Rate The corrosion rate value has much importance in the mechanical parts choice or the interval between the beginning of their use and their failures, which depends on both the metal type and corrosive media. Weight loss method is used to calculate the Corrosion rate. In this method, the weight loss from unit area per unit of time represents the corrosion rate [5], [18] C = W /A. t (2) Where : C : Corrosion Rate (g/cm². hr) W : Weight loss ( gm ) the deference in weight of the specimen before and after exposed to the stream of water. W / A (g/cm²) : Weight loss ( per surface area ) A: surface area of the specimen exposed to the stream of water (cm²) t : exposed time to the stream of water ( hr ) 3. EXPERIMENTAL WORK This work included an evaluation of aluminum alloys which are chemically analysed by using an atomic emission spectro photometer. 3.1 The chemical compositions of alloy is listed in Table (1). Table 1 The Chemical Composition of Alloys. zn Mn Cu Fe Al Preparation of the Specimens Specimen of a square shape ( 10x10x3 ) mm 3, used in this test to measure the erosion / corrosion resistance and hardness. This specimen was grinding by an emery paper of grades (100, 150, 500). then washed in deionized water and dried by air. After that the specimen was polished with nap cloth containing alumina particles size of (5µm) by using the polishing machine ( type : struers knuth rotor, model : DAP-V ),then washed in alcohol and dried editor@iaeme.com

4 Tap Water Effect on Some of Mechanical Properties of Aluminum Alloys 3.3 Vickers hardness Vickers hardness instrument used as the hardness tester type [Tokyo Testing Machine mfg Co.] Ltd. In this test (6) readings for each specimen were taken and the average of the diagonals of each indentation were measured from equation (1) as shown in Table (2).The hardness of the other tests are shown in table (3) Table 2 Represents Values Of Diameter And Vickers Hardness For Original Alloy Test Number Average Diameter mm Vickers Hardness kg/mm² Heat treatment Heating the specimen to 500 ºC for 15 hrs and cooling by air to homogenizing, then heating to 520ºC for 1.5 hrs and quenched in water before test Erosion - Corrosion Test This test was applied on the alloys that were heat treated for various intervals. A direct water jet was used to achieve the erosion/corrosion effect by using a system suitable for this purpose shown in figure (1). At the end of each time in this test the specimen was dried and weighed to measure the weight loss.the corrosion rate was calculated as in equation (2). The results of erosion/corrosion for the specimen used in this test for deferent exposure time are listed in table (4),which include the relationship between the weight loss & exposure time, and the relationship between the corrosion rate(cr) & exposure time. Table 3 Represents Values Of Vickers Hardness At Different Times Exposed Time (hr.) Hardness Hv ( Kg / mm² ) editor@iaeme.com

5 Abdul Khaliq A. Hasan 3.6. Erosion corrosion system The system used in this study, Figure. (1) was designed to measure the erosion/corrosion resistance for the tested alloys specimens, which consist of two basins of water. The size of each basin is (50 x 50 x 25) cm. One of these two basins is placed in a position of (80) cm height.a little clipper is used to hold the specimen inside the upper basin while the other basin is placed on the ground. A water pump (0.5 HP ) is used to circulate the water between the two basins. The water strikes the specimen by a jet which is about (2.5 cm) apart from the specimen.the Nozzle used of 0.5 cm Diameter. The water speed is (3.2) m /sec and the flow rate is (0.9) m 3 / hr. The weight loss is measured at different times interval by digits sensitive balance type (Sartorius BL 210S). Figure 1 Erosion-corrosion system Table 4 Represented Weight Loss & Corrosion Rate Exposure Time (hr.) Weight loss w/a (g/cm²) Corrosion Rate CR (g/cm².hr) editor@iaeme.com

6 Tap Water Effect on Some of Mechanical Properties of Aluminum Alloys 3.7. Water Composition Analysis : The tab water analyzed as shown in a Table (4) [6]. Table 5 The Chemical Analysis Of Tab Water Type of analysis Measuring limit Tab water ph Electrical Conductivity mµs/cm 4560 TDS 3192 TH 1500 Cl Ca Ca as CaCO Mg as CaCO SO P-Alkalinity 0.0 M- Alkalinity 150 Fe TDS : Total Dissolve Solid TH : Total Hardness 4. DISCUSSION The results of the present experimental work concerning the mechanical properties (hardness) and corrosion rate of the aluminum alloy. In Figure. (2) shows the weight loss of specimen as a function of exposure time.it can be seen that the weight loss increase with increasing exposure time ( )hr because of continuously destroyed the forming oxide layer by collision of dissolving solid particles and the chemical reaction of water with surface of alloy continuously as well as the oxide layer be weak adhesive and will be destroyed the layer.after that the alloy forming new and hard oxide layer and weight loss almost remains constant at long exposure times and which leads to high resistance to the reaction of both chemical and mechanical corrosion of water. Which is noticed high corrosion rate ( g/cm².hr) at (0.5 hr) and then decreasing the corrosion rate( g/cm².hr) at the exposure time (15 hr) due to forming new and hard oxide layer which is decreasing the corrosion rate as shown in Figure.(3). Figure.(4) show the relation between hardness and exposure time noticed increasing semi linear relation ship due to continuous collision between high speed water and specimen which is lead to increasing strain hardening like forging process [1], [20]. 5. CONCLUSION 1- Weight loss increased at first hours (till 3 hrs) then be stable. 2- Corrosion Rate increased to maximum after ( 0.5 hr) then decrease gradually, and be at low rate after more than ( 10 hrs ) of exposed time. 3- Increasing the Hardness with increasing exposure time editor@iaeme.com

7 Abdul Khaliq A. Hasan REFERENCES [1] Heat Treatment Reference Guide" May.(18),(2004). [2] R. A. Higgins, Engineering Metalurgy (part 2 ), U.S.A. (1975) [3] R.Kenneth. Trethewey, ''Corrosion''1st &2end edition P.348. UK,(2001). [4] F. king, M.I.N., " Aluminum and its Alloy" British Alcan Testing Lab.-Orie, (Vol. 1), U. K., (1990). [5] / matselect / corralumin.htm "Corrosion of aluminum alloys " [6] A,A. Amjad. " Effects of Graphite Addition on the Mechanical Properties of Al-Si Alloys " M.Sc. Thesis, University of Basrah Iraq, (2006). [7] V. Vesnamaksimovic,S.Velimir,M.Jovanovic, ''The effects of microalloying with Si and Ge on microstructure and hardness of a commercial aluminum alloy'' J.Serb. Chem.Soc.(Vol.68,No.11, pp ), U.S.A.(2003). [8] Y.Ohmori, Y.Matsuura,Nakai & S. Kobayashi "Effect of excess Si content on the aging Behavior Solution-treated Al-Mg-Si alloys " -Alloys.htm,(2001). [9] Tony Anderson CEng. " How and why alloying elements are added to aluminum " (2009) [10] H.Snelson Engineers " Aluminum Extrusions Aluminum Fabricators " Nat Lane, Wharton Industrial Estate, Winsford,Cheshire,CW7 3BS, UK,(2007). [11] S. A. Al-Mtori "The Effect of of Zr & Te on some properties of 7075 & 2024 " M. Sc. Thesis, University of Baghdad, Iraq ( 1992 ) editor@iaeme.com

8 Tap Water Effect on Some of Mechanical Properties of Aluminum Alloys [12] S. W. Kwon, "Effect of over-aging properties of Cu, Ni Containing AC8A Aluminum casting alloy", Seoul National University and Dong Yang pistonco. Ltd., Korea, (2001). [13] A.Abtehal. " Study the erosion behavior of Aluminum-Lithium alloy " M.Sc.Thesis, University of Technology. Iraq, (1992). [14] P.A. Schweitzer,P.E., "Corrosion & Corrosion Protection" Hand book ( U.S.A) Marcel Dekker, Inc, (1989). [15] S. W. Kwon, " Effect of Over-aging on the Microstructure and Mechanical Properties of Cu, Ni Containing AC8A Alominum Casting Alloy" Seoul National University and Dong Yang piston Co. Ltd., KOREA, [16] " Heat treating of aluminum and aluminum alloys ". [17] M.Ravi, U.Pillai, B.Pai,A.Damodaran, " Metallurgical & Materials Transactions A", ( Voi.33A, pp39 ), U.S.A. February, [18] Ullmanns "Encyclopedia of Industrial Chemistry Release Corrosion " 6th Edition,(2002). [19] Safaa,A.S. Almtori " The measurements of some mechanical properties and corrosion resistance of commercial aluminum alloys " J.Basrah Researches (Sciences) Vol.34/No FEB.(2008) [20] A,N. Taher. "Study The Effects of Addition ( Cu, Cd) on some Mechanical Properties And Corrosion Resistance of Al-Si-Mg Alloys " M.Sc. Thesis, University of Basrah, Iraq, (2006). [21] D.Muruganandam, (2011) Friction Stir Welding Process Parameters For Joining Dissimilar Aluminum Alloys, International Journal of Mechanical Engineering and Technology, 2(2), pp [22] Mustafa A. Rijab, Ali I. Al-Mosawi, Improve Microstructure of Aluminum Alloys By Modification, International Journal of Advanced Research in Engineering and Technology, 5(6), pp [23] Sreekala P, Visweswararao K,(2012) A Methodology For Chip Breaker Design At Low Feed Turning of Alloy Steel Using Finite Element Modeling Methods, International Journal of Mechanical Engineering and Technology, 3(2), pp AUTHOR S DETAILS Abdulkhaleq Abdali Hasan, Mechanical engineering from University of Technology Baghdad- Iraq at 1976, working as a lecturer in Technical Institute of Basrah / Southern Technical University - Iraq since 1978, Authored book in Metal Manufacturing Process and Published three research papers, Completed his M.Tech. in Production Engineering form Sam higginbottom Institute of Agriculture Technology & sciences, at 2014,Allahabad, U.P, India editor@iaeme.com