scholarly journals Joining of Stainless Steel with Novel Filler Material and its Weldability Studies

2020 ◽  
Vol 2 (2) ◽  
pp. 18-19

Welding of Austenitic Stainless steels results in the emission of hexavalent chromium [Cr+6] fumes due to the presence of 18-22% chromium content in the stainless steel base and its filler materials. These hexavalent fumes are carcinogenic and cause respiratory problems to the welders and personnel in the vicinity of welding. In the present research work, novel Chromium free Nickel-based filler material of % wt composition 41 Ni, 8 Co, 16 Fe, 14Mo, 7 Mn, 8 Cu, 3 Nb, 1 Ti, 1 Si, 1 Al is developed and its weldability with stainless steel is studied. The microstructure and chemical composition of different metallurgical phases in the filler material and weld joints are studied using different microscopy tools and X-Ray Diffraction, respectively. The ultimate tensile strength of the filler material and weld joint welded by developed filler material is found to be 536MPa and 487 MPa, respectively. The average hardness and toughness of the filler material and welded joint are 190VHN &110J and 209VHN & 89 VHN, respectively. Results of Potentio-dynamic polarization and Inter Granular corrosion cracking (IGCC) of the weld joint has shown the corrosion rate of 1.575e-004 mils/year and 354.56 miles/year, respectively. Mechanical properties and corrosion rate of weldments welded by novel filler material are compared with that of conventional filler material. Design of experiments(DOE) using Taguchi L9 array is formulated to understand the influence of Welding current, root gap, and gas flow rate on output parameters such as Tensile Strength, Toughness, and corrosion resistance of weldment. DOE using RSM has shown maximum Tensile strength of 487Mpa, maximum Hardness of 209 VHN, and a minimum corrosion rate of 1.575e-004 mils/year has obtained with an optimum current value of 130A, 11.79 litres/min gas flow rate, and 2.33mm root gap.

Metals ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 1443 ◽  
Author(s):  
Maroš Vyskoč ◽  
Miroslav Sahul ◽  
Mária Dománková ◽  
Peter Jurči ◽  
Martin Sahul ◽  
...  

In this article, the effect of process parameters on the microstructure and mechanical properties of AW5083 aluminum alloy weld joints welded by a disk laser were studied. Butt welds were produced using 5087 (AlMg4.5MnZr) filler wire, with a diameter of 1.2 mm, and were protected from the ambient atmosphere by a mixture of argon and 30 vol.% of helium (Aluline He30). The widest weld joint (4.69 mm) and the highest tensile strength (309 MPa) were observed when a 30 L/min shielding gas flow rate was used. Conversely, the narrowest weld joint (4.15 mm) and the lowest tensile strength (160 MPa) were found when no shielding gas was used. The lowest average microhardness (55.4 HV0.1) was recorded when a 30 L/min shielding gas flow rate was used. The highest average microhardness (63.9 HV0.1) was observed when no shielding gas was used. In addition to the intermetallic compounds, β-Al3Mg2 and γ-Al12Mg17, in the inter-dendritic areas of the fusion zone (FZ), Al49Mg32, which has an irregular shape, was recorded. The application of the filler wire, which contains zirconium, resulted in grain refinement in the fusion zone. The protected weld joint was characterized by a ductile fracture in the base material (BM). A brittle fracture of the unshielded weld joint was caused by the presence of Al2O3 particles. The research results show that we achieved the optimal welding parameters, because no cracks and pores were present in the shielded weld metal (WM).


2019 ◽  
Vol 969 ◽  
pp. 625-630
Author(s):  
A. Sivanantham ◽  
S. Manivannan ◽  
S.P. Kumaresh Babu

Dissimilar welding of 3mm thickness of AISI 304L austenitic stainless steel plate and AISI 430 ferritic stainless steel plates were performed by Tungsten Inert Gas welding without any filler material by using argon as shielding gas. Welding is carried out according to set of combinations of welding parameters such as welding current (levels of 135,140,145 Ampere), welding speed (levels of 105, 110, 115 mm/min) and shielding gas flow rate (of levels 5,10,15 Litre/min) obtained through Taguchi L9 orthogonal approach for maximizing the ultimate tensile strength by using MiniTab software . Radiography test was performed to know the soundness of the welds. Tensile specimens are fabricated as per ASTM E8 standard for tensile testing. Microstructural observations of the weld are performed. Correlations have been obtained to know the effect of welding speed, welding current and shielding gas flow rate on tensile strength and an optimum level of parameter is obtained at welding current of 145 Ampere, welding speed of 115 mm/min and shielding gas flow rate of 5 Litre/min.


2018 ◽  
Vol 9 (1) ◽  
pp. 9-16
Author(s):  
S. A. Rizvi

This research article is focusing on the optimization of different welding process parameters which affect the weldability of stainless steel (AISI) 304H, Taguchi technique was used to optimize the welding parameters and the fracture mode characterization was studied. A number of experiments have been conducted. L9 orthogonal array (OA) (3×3) was applied. Analysis of variance ( ANOVA) and signal to noise ratio (SNR) was applied to determine the effect of different welding parameters such as welding current, wire feed speed and gas flow rate on mechanical, microstructure properties of SS304H. Ultimate tensile strength (UTS), toughness, microhardness (VHN), and mode of fracture was examined to determine weldability of AISI 304H and it was observed from results that welding voltage has major impact whereas gas flow rate has minor impact on ultimate tensile strength of the welded joints. Optimum process parameters were found to be 23 V, 350 IPM travel speed of wire and 15 l/min gas flow rate for tensile strength and mode of fracture was ductile fracture for tensile test specimen.


2020 ◽  
Vol 8 (4) ◽  
Author(s):  
Neeraj Sharma ◽  
◽  
Wathiq Sleam Abduallah ◽  
Manish Garg ◽  
Rahul Dev Gupta ◽  
...  

Tungsten Inert Gas welding is a fusion welding process having very wide industrial applicability. In the present study, an attempt has been made to optimize the input process variables (electrode diameter, shielding gas, gas flow rate, welding current, and groove angle) that affect the output responses, i.e., hardness and tensile strength at weld center of the weld metal SS202. The hardness is measured using Vicker hardness method; however, tensile strength is evaluated by performing tensile test on welded specimens. Taguchi based design of experiments was used for experimental planning, and the results were studied using analysis of variance. The results show that, for tensile strength of the welded specimens, welding current and electrode diameter are the two most significant factors with P values of 0.002 and 0.030 for mean analysis, whereas higher tensile strength was observed when the electrode diameter used was 1.5 mm, shielding gas used was helium, gas flow rate was 15 L/min, welding current was 240A, and a groove angle of 60o was used. Welding current was found to be the most significant factor with a P value of 0.009 leading to a change in hardness at weld region. The hardness at weld region tends to decrease significantly with the increase in welding current from 160-240A. The different shielding gases and groove angle do not show any significant effect on tensile strength and hardness at weld center. These response variables were evaluated at 95% confidence interval, and the confirmation test was performed on suggested optimal process variable. The obtained results were compared with estimated mean value, which were lying within ±5%.


Author(s):  
A.H. Alwan ◽  
N.Y. Mahmood

Purpose: The influence of metal active gas welding variables, including current, wire feeding speed and gas flow rate on the ultimate tensile strength and critical buckling load of steel (St.24) and the optimized welding conditions were discussed. Design/methodology/approach: The experimental steps are firstly designing the experiments, secondly conducting the mechanical tests, thirdly analysing the results through Minitab 16 and finally determining the optimum welding parameters. Confirmation tests of the optimized variables were validated. Findings: ANOVA approach manifested that the significant effect of welding variable on the tensile strength was the gas flow rate, while the current was on the critical buckling load. The results are confirmed and given the optimum values. Research limitations/implications: The influence of MAG welding variables (current, wire feeding speed and gas flow rate) on the tensile and buckling strengths of steel will be investigated in order to avoid the failure of many welded assemblies in the structures due to the buckling, in addition to reduce the requirement of long time and high cost to produce such assemblies. Therefore, it is necessary to find a solution to encounter the difficulties in their welding process. Practical implications: The major challenge was how to reduce the time and cost beside gaining the optimum properties through the designed experiments. Originality/value: The results may be helpful to design any welded joints in machine frames, structural steel connections and crane structures at the optimum condition.


2012 ◽  
Vol 1380 ◽  
Author(s):  
Estrella Martínez-Ramos ◽  
Roberto Pérez-Garibay ◽  
Jorge Rubio-Rojas

ABSTRACTAn identification of the characteristics of microbbubles dispersion is presented in this paper, when frother addition (MIBC) is modified in a biphasic system (air-water). Sauter diameter (d32), gas flow rate (Jg), superficial area flow density of the microbubbles (Sb) and air holdup (εg) are the measured variables in this research work. The studied frother additions were 0, 10 and 20 ppm. Similar to conventional bubble sizes, it was observed also, that air holdup increases with the air flow rate. The linear relationship between εg and Sb permits to conclude that superficial area flow density, a variable difficult to measure directly, may be estimated if air gas holdup is known. Furthermore, the experimental results showed that frother addition (MIBC) reduced the Sauter diameter, increasing all other variables.


2017 ◽  
Author(s):  
MUHAMMAD NAZMI HAKIM BIN RIDZUAN

Gas tungsten arc welding is the process repairing and widely used in heavy engineering for joining metal. It can be uses for various type of metal and application. The aim of this project is to study the effects of 304 stainless steel with 3 mm thickness on mechanical properties and its microstructure analysis towards gas tungsten arc welding method. The variables set up in this project were current, gas flow rate and welding direction upon rolling direction of stainless steel sheet. Three current setup were used which is 60 A, 80 A and 100 A Type of filler metal used in this project was ER 308L with 1.6 diameter. Two set up for gas flow rate were used which is 8 l/m and 12 l/m. Testing that carried out were tensile test, Vickers macro hardness test with 10 kgf load and microstructure analysis by using optical microscope. The effects of microstructure in austenitic stainless steel welds is discussed. From the mechanical properties procedures, the strength of the weld metal was obtain. For hardness testing, the most important zone to be focused were heat-affected zone (HAZ) and weld metal (WM). The integrity of the welding tested by using tensile test and hardness test with different amount of current and gas flow rate.


2020 ◽  
Vol 22 (4) ◽  
pp. 1121-1132
Author(s):  
Saadat Ali Rizvi ◽  
Wajahat Ali

AbstractThis study is centre on optimizing different welding parameters which affect the weldability of SS304H, Taguchi technique was employed to optimize the welding parameters and fracture mode characterization was studied. A number of experiments have been conducted. L9 orthogonal array (3×3) applied for it. Analysis of variance (ANOVA) and signal to noise ratio (SNR), a statistical technique was applied to determine the effect of different welding parameters such as welding current, wire feed speed and gas flow rate on weldability of SS304H. Tensile strength, toughness, micro hardness and mode of fracture was examined to determine weldability of SS304H and it was observed from result that welding voltage have major impact whereas gas flow rate has minour impact on ultimate tensile strength of the welded joints and optimum process parameters were found to be 23 V, 350 IPM travel speed of wire and 15 l/min gas flow rate for tensile strength and mode of fracture was ductile fracture for tensile test specimen.


2021 ◽  
Vol 6 (3) ◽  
pp. 81-84
Author(s):  
C. E. Etin-Osa ◽  
L. M. Ebhota

Metals are often subjected to various types of stresses, usually under tensile stress, quick failure of material can be encouraged especially when poor combinations of process parameters are employed in joining of the material. Tensile strength is regarded as the maximum stress that a material can sustain under tension. The aim of this study is to predict the weld tensile strength of tungsten inert gas (TIG) mild steel welds using Response Surface Methodology (RSM), with the purpose of achieving optimum results. The input parameters considered were current, voltage, and gas flow rate. The TIG welding process was used to join two pieces of mild steel plates, after which tensile test was conducted on the specimen. The experimental result was analyzed using the RSM. Weld Tensile test of 596.218MPa with a desirability value of 95.70% was observed to be the best, resulting from the optimized process parameters of current of 120.00 Amp, voltage of 20.00 volt and gas flow rate of 12.00 L/min.


Author(s):  
M. Mostafizur Rahman ◽  
Shaon Talukdar ◽  
Mohammad Asaduzzaman Chowdhury ◽  
Rasel Khan ◽  
Abdullah A. Masum ◽  
...  

A hot filament thermal chemical vapor deposition (CVD) reactor was used to deposit solid thin films on stainless steel 316 (SS 316) and stainless steel 201 (SS 201) substrates at different flow rates of acetylene (C2H2) gas. The variation of thin film deposition rate with the variation of gas flow rate has been investigated experimentally. During experiments are conducted under gas flow rate (1-5) lit/min gas flow rate, duration of deposition (10-60 min), pressure (0.2-1 bar), average surface roughness (0.3-1.05) µm and temperature 800 °C considered. Experimental results show that deposition rate on SS 316 and SS 201 increases with the increase in gas flow rate. The deposition rate also shows increasing trend with pressure and duration of deposition. Under the above mentioned experimental conditions deposition is found to be maximum of SS-316 compared to SS-201. In relation to roughness the maximum deposition is found at 0.5 microns but comparing the both materials -316 and-201 highest of deposition rate is obtained from SS-316.


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