GRD Journals- Global Research and Development Journal for Engineering | Volume 4 | Issue 6 | May 2019 ISSN: 2455-5703
Dissimilar Steel Alloys Welding Joint Process Parameters Optimization Ashwani M.Tech Student Department of Mechanical Engineering CBS Group Jhajjar
Kuldeep Singh Assistant Professor Department of Mechanical Engineering CBS Group Jhajjar
Abstract Nowadays, the customer satisfaction is the major responsibilities and duties of the organizations management. In this research paper we find the best optimized welding joints with process parameters such as: welding current, welding voltage and gas flow rate for the best tensile strength and micro-hardness of the welding joints. Taguchi method which reduces the variation in process through design of experiments has been used. In this study presents an efficient method for determining the optimal Gas Metal Arc Welding parameters for increasing the weld ability of Stainless Steel 202 & Stainless Steel 304 under varying condition through the use of Taguchi parameter process. The study shows that the optimum parameters for tensile strength are found when Welding Voltage is at 18 Volts, Welding Current at 50 Amps and Gas Flow Rate at 15 L/min and optimum parameters for hardness are found when Gas Flow Rate is at 15 L/min, Welding Current at 75 Amps and Welding Voltage at 18 Volts. From ANOVA it is found that welding parameters significantly affects the weld quality of Stainless Steel 202 and Stainless Steel 304. Keywords- Welding, Welding Joint, Taguchi Approach
I. INTRODUCTION The process of welding is a procedure of joining similar and dissimilar metals with the use of filler material usually in form of a rod and with or without the application of pressure. During welding procedure, metals or thermoplastics are welded. In simple terms, welding involves the use of four components which are: the metals, a heat source, filler metal, and some kind of shield from the air. The metals are heated to their melting point while being shielded from the air, and then a filler metal is added to the heated area to produce a single piece of metal. The welding process is broadly utilized as a part of domestic and industrial purposes, for example, joining of railway lines, ship building, roadways, bridges and machinery’s parts etc. The methodologies of brazing and soldering are similar to the welding process. Arc welding is one of the most famous process among the welding processes. This kind of welding was firstly seen in the late part of the 19th century. The Metal Inert Gas welding is an arc welding process where solid consumable wire electrode is fed with the help of welding torch between work pieces. Joining the two materials properly, or in this process electric arc are forms between work piece and wire electrode, which heat and melts the metals and join them. A shielding gas is also used which feeds through with the welding torch or gun to protect the weld area from environmental conditions, such gases are argon, helium, carbon dioxide, nitrogen etc. Mostly CO2 is widely used in MIG welding, because it is least expensive and used for deeper penetration etc. This type of welding process can be automatic and semi-automatic. For MIG welding thickness of metal should be more than 3mm. The most commonly power source of MIG welding are constant voltage and direct current are used. There are some following metals are used for MIG welding such as, Mild steel, Stainless steel and Aluminium etc. 1) Mild steel is easily weld and have less amount of problems. 2) Aluminium is difficult to weld with MIG welding due to oxides are deposited during welding process. But easily weld with TIG welding. 3) Stainless steel is easily welded but requires more skill than mild steel. MIG welding can be easily done using ferrous and nonferrous metals and has great role in industries due to its flexibility, and higher deposition rates etc.
II. LITERATURE REVIEW Taichi Murakami et al. [1] studied that dissimilar metal joining of aluminium to steel which was difficult because of the formation of the brittle metallic compound at the interface of the welded joint. M. Marya et al. [2] in this research, the author describes that the joints of dissimilar metals and alloys were an essential part of domestic devices and heat exchange systems and the difficulty was to develop and implement fast and cost effective industrial procedures to join aluminium with copper or stainless steel. After inspection it was found that properties of weld such as mechanical, electrical etc and microstructures were controlled. H.T. Zhang et al. [3] observed the microstructure and properties of aluminium-zinc coated steel lap joints done by joints made by modified metal inert gas CMT welding. After the tensile tests were done, it showed that the welding process was capable of providing good aluminium-zinc coated steel joints. K. Kishore et al. [4] investigated that welding of materials such as steel is
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Dissimilar Steel Alloys Welding Joint Process Parameters Optimization (GRDJE/ Volume 4 / Issue 6 / 002)
critical. They studied the defects in Gas Shielding Arc welding (TIG and MIG) of AISI 1040 were done. Taguchi techniques were used to describe the orthogonal array. The data obtained were checked on ANOVA. The data was collected using the Ultrasonic Testing in which angle beam testing was used for testing the weldments. The results of the specimens showed the presence of defects such as LOP, Blowhole, LOF and cracks. H.T Zhang et al. [5] in this literature lap joints of two dissimilar material welding was done between 1 mm thick magnesium and aluminium alloy plates by using MIG welding in which zinc foil was used as a barrier layer and a crack free joint was obtained. The tensile strength was done on the lap joint and the value obtained was 64 MPA. Satyaduttsinh P. Chavda et al. [6] this research paper presented the impact of MIG welding parameters such as wire feed rate, gas flow rate, welding current etc on the weld pool geometry and weld strength of Medium Carbon Steel material during the welding process. DOE method was used to optimize the welding parameters to find the best parameters combinations. Experimental based Taguchi techniques were used to acquire the date and analysis of Variance (ANOVA) and an orthogonal array were used to study the welding characteristics. Gejendhiran S. et al. [7] this review article investigated the influence of welding parameters on the mechanical properties MIG welding and GAs Tungsten Arc Welding (GTAW). The review paper shows the effect of various welding parameters such as shielding gas, welding speed, current, voltage etc on the mechanical properties of welding.
III. EXPERIMENTAL PROCEDURE A. Taguchi Design Method Taguchi technique is a part of quality engineering and is also one of the great engineering methods which was developed in 20th century and was developed by a Japanese engineer ‘Genichi Taguchi’. Taguchi methods utilize the two, three and mixed levels factorial designs. This method focuses on the engineering applications than the advanced statistical technique. The main aim and purpose of the Taguchi method is to provide better quality at minimum price. Taguchi technique develop the methods for the design of experiments which to investigate how the dissimilar parameters affects the variance and mean process parameters. In Taguchi technique design of experiments is proposed where ‘OA’ which to organize the input parameters and different levels at which varies. Taguchi technique is best and used when an intermediate no. of variances such as, 4 to 55 between some variables and few variables are contributes which refer the designs as “off-line quality control” because it ensuring the good quality performance in the design stage. Taguchi technique is used for both shop floor and upstream quality engineering. Shop floor is based on the cost, maintenance quality and real time for monitoring and upstream method is used for small scale and to reduce the cost, variability and market place. And also more improvement technique which reduces the time and cost etc. The Taguchi technique uses the outer orthogonal array which forces the noise to experiments variation. The processes are generally subjected to the various noise factors that combine the variation of response. The extremely noise system which is not necessary to identified the many parameters which are controllable and then analyze with using S/N ratio. In third objective optimum conditions which are established by S/N ratio and no outer arrays are used and at each experiments conditions experiments are repeated three times. 1) Signal- Noise Ratio Taguchi technique uses the S/N ratio and to minimize the quality of products variation due to various parameters. There are following three types of S/N ratio can be used such as: 1) Smaller the Better n = -10 Log10 [mean of sum of squares of measured data] 2) Larger the Better n = -10 Log10 [mean of sum squares of reciprocal of measured data] 3) Nominal the Best n = 10 Log10 [square of mean/variance] To get the optimal welding performance, Larger-the-better characteristic has been used in this paper.
IV. MATERIAL The materials that were used in the research paper were Stainless Steel 202 and Stainless Steel 304 with dimension (100X75X75 mm3). Table 1: Chemical composition of Stainless Steel 202 Fe Cr Mn Ni Si N C P S 68 17-19 7.50-10 4-6 ≤ 1 ≤ 0.25 ≤ 0.15 ≤ 0.060 ≤ 0.030 Table 2: Chemical composition of Stainless Steel 304 Element Fe Cr Mn Ni Si C P S % contribution Balance 17.5-20 ≤ 2 8-11 ≤ 1 ≤ 0.08 ≤ 0.045 ≤ 0.030
Element % contribution
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Dissimilar Steel Alloys Welding Joint Process Parameters Optimization (GRDJE/ Volume 4 / Issue 6 / 002)
V. PROCESS PARAMETER SELECTION A. Selection of Process Parameters In this research there are mainly eight parameters are used. But during MIG Welding operation three parameters are used. This can optimize the strength and hardness of welding operation. The following processes parameters were selected for this experimentation work. Welding Current - A Welding Voltage - B Gas Flow Rate - C Table 3: Selection of process parameters S.NO. SYMBOL PROCESS PARAMETERS UNIT 1 A Welding Current Amp 2 B Welding Voltage Volt 3 C Gas Flow Rate L/min Table 4: Parameters, symbols, and level values used for the orthogonal array PARAMETERS SYMBOLS LEVEL 1 LEVEL 2 LEVEL 3 Welding Current (Amp) A 50 75 100 Welding Voltage (Volt) B 15 20 18 Gas Flow Rate (L/min) C 15 10 20
Selection of process parameter and their levels are described in the following Table No. 5 RUN 1. 2. 3. 4. 5. 6. 7. 8. 9.
Table 5: Experimentation Matrix CURRENT VOLTAGE GAS FLOW RATE (Amp) (Volt) (L/min) 50 15 15 50 20 10 50 18 20 75 15 10 75 20 20 75 18 15 100 15 20 100 20 15 100 18 10
Fig. 1: All nine specimens prepared by using MIG welding
VI. RESULTS AND DISCUSSIONS In this present study, MIG welding of Stainless Steel 202 and Stainless Steel 304 has been done by selecting three parameters i.e. welding current, welding voltage and gas flow rate with the help of literature survey. Need of selecting these three parameters is just because of these three parameters have the greatest effect on the weld bed geometry. The study is conducted with the help of 9 work pieces. L9 (3*3) orthogonal array is used on the basis of Taguchi design process. For the optimization of the welding parameters, Taguchi method is very useful. All rights reserved by www.grdjournals.com
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Dissimilar Steel Alloys Welding Joint Process Parameters Optimization (GRDJE/ Volume 4 / Issue 6 / 002)
Table 6: Response table of Tensile strength versus current, voltage and gas flow rate LEVEL WELDING CURRENT WELDING VOLTAGE GAS FLOW RATE 1. 53.69 48.99 53.43 2. 50.77 50.91 51.14 3. 50.01 54.57 49.90 DELTA 3.68 5.58 3.52 RANK 2 1 3 Table 7: Optimum parameters levels for the tensile strength RANK 1 Welding Voltage Level 3 18 Volts RANK 2 Welding Current Level 1 50 Amps RANK 3 Gas Flow Rate Level 1 15 L/min Table 8: Response Table for S/N Ratio of Hardness on weld areas LEVEL WELDING CURRENT WELDING VOLTAGE GAS FLOW RATE 1. 52.35 52.89 54.24 2. 54.31 53.10 54.17 3. 52.99 53.66 51.24 DELTA 1.96 0.77 3.00 RANK 2 3 1 Table 9: Optimum parameters levels for the hardness at weld area RANK 1 Gas Flow Rate Level 1 15 L/min RANK 2 Welding Current Level 2 75 Amps RANK 3 Welding Voltage Level 3 18 Volts
VII. CONCLUSIONS The study, by using Taguchi technique, found that in the case of tensile strength, welding voltage has the most significant effect followed by welding current and gas flow rate. In case of hardness, it is found that gas flow rate has the most significant effect followed by welding current and welding voltage. Taguchi method is very useful in designing of the high quality products. With the help of human judgments, we cannot control the various design parameters settings and if we do then it is very time and cost consuming.
REFERENCES [1] [2] [3] [4] [5] [6] [7]
Taichi Murakami, Kazuhiro Nakata, Hongjun Tong and Masao Ushio. 2003. "Dissimilar Metal Joining of Aluminium to steel by MIG Arc Brazing Using Flux Cored Wire" ISIJ International, Vol. 43 (2003), No.10, pp.1596-1602 M. Marya, S. Marya , D. Priem. 2005. "On the characteristics of Electromagnetic welds between Aluminium and other Metals and Alloys." Welding in the World, Vol. 49 H.T Zhang, J.C. Feng, P. He, H. Hackl. 2006. "Interfacial microstructure and mechanical properties of aluminium-zinc-coated steel joints made by a modifies metal inert gas welding-brazing process: Elsevier Journals K.Kishore, P.V.Gopal Krishna, K. Veladri and Syed Qasim Ali. 2010. "Analysis of defects in gas shielded welding of AISI1040 Steel using Taguchi Method." ARPN Journal Engineering and Applied Sciences H.T. Zhang, J.Q. Song. 2011. "Microstructural evolution of aluminium/magnesium lap joints welded using MIG process with zinc foil as an interlayer." Elsevier Journals. Satyaduttsinh P. Chavda, Jayesh V. Desai, Tushar M. Patel. 2014. "A review on optimization of MIG Welding parameters using Taguchi's DOE Method." Vandana Publications, Volume-4, Issue-1. Gejendhiran S., Satheesh Kumar K V, Dr. Sivakumar A. 2014. “A study of welding parameters on mechanical properties of Gas Metal Arc Welding and Gas Tungsten Arc Welding: A Review." International Journal of Advanced Engineering Research and Studies E-ISSN2249-8974.
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