Asian Research Consortium

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1 Asian Research Consortium Asian Journal of Research in Social Sciences and Humanities Vol. 6, No. 12, December 2016, pp Asian Journal of Research in Social Sciences and Humanities ISSN A Journal Indexed in Indian Citation Index DOI NUMBER: / Category:Science and Technology Intensifying the Mechanical Properties of Is-4454/1981 Spring Steel Material T. Bhuvanesh Kumar*; N. Balaji**; J. Esakiappan*** Abstract *Assistant Professor, Department of mechanical Engineering, P. S. V. College of Engineering and Technology, Krishangiri, India. **Associate Professor, Department of Mechanical Engineering, Sri Krishna College of Engineering and Technology, Coimbatore, India. ***Assistant Professor, Department of Mechanical Engineering, SRM Easwari Engineering College, Chennai, India. All engineering materials like steel are heat treated under limited cycle of heating and cooling to modify their mechanical properties to achieve required engineering application. In this research work various mechanical properties like young s modulus, tensile strength, ductility and yield strength were studied for the different heat treatment process on IS-4454/1981 spring steel.the IS- 4454/1981 spring steel sample was heat treated in an electric furnace at different temperature levels and holding for different time intervals and then cooled in different media, The mechanical properties like ductility, tensile strength, yield strength and young s modulus of the treated and untreated samples were determined using a universal testing machine. The results notify that the mechanical properties of IS-4454/1981 spring steel material were altered significantly. By rising the tempering time and temperature, hardness and ultimate tensile strength are steadily decreased and the ductility was enhanced. The optimum temperature and time interval were established for balanced mechanical properties. Keywords: Heat treatment; Tensile strength; Yield strength; Young s modulus; Quenching. 681

2 1 Introduction Heat treatment of metals is an important operation in the final process of many engineering components. The object of this process is to make the metal better suited, structurally and physically, for some specific application. All metal can be subjected to thermal cycling. But the effect of thermal cycling may differ from one to another. The heat treatment has significant impact on steels, and its properties may be changed considerably by definite heating and cooling cycles. Heat treatment may improve the following, Relieving internal stresses Improvement in ductility Improvement in machinability Refinement of grain size Improvement in toughness Development of recrystallized structure in cold worked metal. Increasing tensile strength to achieving changes in chemical composition of metal surface. Heat treatment temperature, holding time, and rate of heating, cooling are some of the parameters which affect the heat treatment process it now as heat treatment process variables. These variables depend on the chemical composition, size and shape of the object and the final properties desired in the metal, this process is employed to relieve internal stresses. No microstructure changes occur during process. It differs from other subcritical treatment in which structure improvement takes place. Internal stresses are those stresses which can exist within a body in the absence of external force. These are known as residual stresses. Internal stresses are developed during different operation like solidification of casting, welding, machining, surface hammering, cold working and phase transformation. The process of stress relieving consists of heating the steel uniformly to a temperature below the lower critical temperature, holding at this temperature for sufficient time, followed by uniform cooling. Uniform cooling is of almost importance as non uniform cooling will itself result in the development of internal stresses. The maximum stress relieving temperature is generally limited to about 600 degree Celsius. Present work is deals with the effect of heat treatment on the mechanical properties of spring steel with the aim to achieve the most enhanced spring steel for increased the life of the spring 2 Methodologies and Experimental Setup 2.1 Analyse of Chemical Composition The chemical composition of the test sample is C-0.86%, Mn-0.76%, Si-0.22%, S-0.005%, P %, Cu-0.010%. Its equivalent grade agrees with IS-4454/1981 Part 1 standard specification. This steel is suitable for light duty helical coil springs, torsion bar springs for vehicle construction. 682

3 2.2 Test Specimen Preparation Kumar et al. (2016). Asian Journal of Research in Social Sciences and Humanities, Types of test piece to be used for wire, bars and sections with a diameter as per ISO 6892: Dimensions of the Test Piece The original gauge length (L0) shall be taken as 200 mm ± 2 mm or 100 mm ± 1mm. The distance between the grips of the machine shall be equal to at least L mm, i.e. 250 mm and 150 mm, respectively, except in the case of small diameter wires where this distance can be taken as equal to L Preparation of Test Pieces If the product is delivered coiled, care shall be taken in straightening it Determination of the Original Cross-sectional Area The original cross-sectional area (S0) shall be determined to an accuracy of ± 1 %. For products of circular cross-section, the original cross-sectional area may be calculated from the arithmetic mean of two measurements carried out in two perpendicular directions. The original cross-sectional area may be determined by the mass of a known length and its density. Standard specimens are prepared with the required dimensions for tensile test. The shape and size of standard dimension chosen for the tests are shown below. 250 mm Figure No. 1 Test Specimen Ø 9 mm 2.3 Furnace Temperature range of 100 to 850 degrees Figure No. 2 Furnace 683

4 2.4 Oil Quenching Oil is used very extensively as a quenching medium as it gives the best proportion between toughness and warpage for standard steels. High-performance tempering oil with extremely high quenching properties. Predominantly for tempering various alloys of construction and tool steels. The specimen was heated to the temperature of 300 C, 350 C,400 C,450 C, 500 C 550 C and directly quenched in the oil bath. 2.5 Water Quenching Figure No. 3 Oil Quenching Normally used fresh water can be taken for quenching The specimen was heated to the temperature of 300 C, 350 C,400 C,450 C, 500 C 550 C and directly quenched in the water bath Figure No. 4 water Quenching 684

5 3.0 Results and Discussions Kumar et al. (2016). Asian Journal of Research in Social Sciences and Humanities, the graph for yield strength vs temperature for diameter 8mm.The results reveal that the yield strength is increasing with increase temperature up to 450 o C and then itgradually decreased. Figure No. 5 Relationship between Yield Strength and Temperature for Diameter 8mm The heat treated sample was tested by universal testing machine and the value are analyzed and put in the graph for tensile strength vs temperature for diameter 8mm.The results reveal that the yield strength is increasing with increase temperature up to 450 o C and then it gradually decreased. Figure No. 6 Relationship between Tensile Strength and Temperature for Diameter 8mm 685

6 the graph for tensile strength vs temperature for diameter 8mm.The results reveal that the yield strength is increasing with increase temperature up to 350 o C and then it gradually decreased Figure No. 7 Relationship between Elongation and Temperature for Diameter 8mm the graph for tensile strength vs temperature for diameter 9mm.The results reveal that the yield strength is increasing with increase temperature up to 450 o C and then it gradually decreased Figure No. 8 Relationship between Yield Strength and Temperature for Diameter 9 Mm 686

7 the graph for tensile strength vs temperature for diameter 9mm.The results reveal that the tensile strength is increasing with increase temperature up to 450 o C and then it gradually decreased Figure No. 9 Relationship between Tensile Strength and Temperature for Diameter 9 Mm the graph for tensile strength vs temperature for diameter 9mm.The results reveal that the tensile strength is increasing with increase temperature up to 450 o C and then it gradually decreased Figure No. 10 Relationship between Elongation and Temperature for Diameter 9 Mm 687

8 4.0 Conclusion The results of this work will help in the spring design and manufacture methodologies. Giving insight in the spring performance under cyclic loads considering as parameters, material type, wire diameter, recommended time and temperature for the heat treatment. with respect to the experiment that was carried out, the readings were observed and it was found that the heat treated specimen with a temperature of 450 C can withstand a maximum load when compared to all other specimens. The commonly used stress relieving method of 225 C with 15 minutes can withstand a maximum load of N. On the other hand the specimen heat treated for 450 C can withstand a maximum load of N. There by the 6% increase in load can be seen clearly. So, we suggest the Spring Material of Grade III with heat treatment of 450 C can be used for many industrial and automotive applications 5.0 Reference J.K.Odusote,T.K.Ajiboye,A.B.Rabiu Evaluation of Mechanical Properties of Medium Carbon Steel Quenched in Water and Oil Journal of Minerals and Materials Characterization and Engineering, 2012, 11, September 2012 Min Shan HTUN, Si Thu KYAW and Kay Thi LWIN Effect of Heat Treatment on Microstructures and Mechanical Properties of Spring Steel in Journal of Metals, Materials and Minerals, Vol.18 No.2 pp , L. Del Llano-Vizcaya, C. Rubio-Gonzalez, G. Mesmacque, Stress Relief on Fatigue and Relaxation of Compression Springs and design 28(2007) C.S. Lee, K.A.Lee, D.M. Li, S.J. Yoo, W.J. Nam Microstructural Influence On Fatigue Properties Of A High-Strength Spring Steel in Material science and Engineering A241(1998) R. Adetunji, P. O. Aiyedun, S. O. Ismaila, M. J. Alao Effect of normalizing and hardening on mechanical properties of spring in Journal of Minerals and Materials Characterization and Engineering, 2012, 11, S. Sharma, K. Jagannath, C.Bhat, U. AchuthaKini, P. R. Prabhu, Jayashree P. K Effect of Heat Treatment on Mechanical Properties of AISI 4147 Spring Steel international conference Automotive and Materials engineering (ICMAME 2013) April 29-30,2013singapore. Indian Standard Metallic Materials - tensile testing at ambient temperature ( III revision) IS 1608 : 2005 ISO 6892 : 1998 D. A. Fadare, T. G. Fadara and O. Y. Akanbi Effect of Heat Treatment on Mechanical Properties and Microstructure of NST 37-2 Steel Journal of Minerals & Materials Characterization & Engineering, Vol. 10, No.3, pp ,

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