A STATISTICAL INSIGHT OVER HAZ HARDNESS IN MMA WELDING

Welding current is most affecting parameter to hardness and aspect ratio both whereas groove design is the most affecting parameter to impact strength.

Powder Metallurgy and Advanced Materials, 2018

The weldability of the steels represents a problem of great interest in order to achieve welded structures that satisfy the high requirements on quality, imposed by the nowadays applications. In this paper has been proposed a more advanced model that has considered more factors of weldability influence, thus allowing a more detailed analysis based on the main welding process variables. Introduction Weldability is a general technological property commonly used in engineering, but very difficult to be defined and quantified in an exact manner. The American Welding Society has defined the weldability as being: “The capacity of a metal to be welded under the fabrication conditions imposed with a specific suitability designed structure and to perform satisfactorily in service” [1]. According to DIN 8528, Part 1 the weldability is seen as the output of the interaction of three main group factors, given in Table 1 [2]. Table 1. The weldability’s factors of influence. MATERIAL WELDING SUITA...

This research dealt statistical analysis of the data that obtained from process of the electric arc welding for samples of the medium carbon steel which its hardness is equal to (156 HB). All welding pieces were produced by changing the practical Parameters, where tolerances of the electrode diameter were (2.5, 3.25, 4) mm and thickness of the steel pieces were (4, 4.25, 4) mm. This research aims to, first the variance analyses of the independent parameters versus quality of hardness in the welding zone. Second, optimization parameters find that effect in the quality of hardness that result from welding by signal-to-noise ratio (Taguchi method). Statistical analysis software (Minitab-16.0) used to generate graphs relative to the experimental results that obtained from tests. Results showed that the thickness and electrode diameter have significant effect in the hardness. Third level of both parametrs got predicted hardness (188.64 HB) and conformed test (186.35 HB) that were mm A 4 3 = , mm B 4 3 = .

In the present research, the effects of spot-welding process parameters on the nugget diameter and electrode penetration depth of spot-welded joints were investigated. To achieve this, a spot-welded joint of three-thin sheet low carbon steels (same thicknesses of 0.8 mm) was simulated as an electericalthermal-mechanical coupling of 3D finite element model. After validating the finite element simulation presented in this study by comparison with the experimental results for the spot diameter, various cases of spot welds were analyzed based on the design on experiment (i.e., Taguchi method). Six variables including electrode force, electric current, and quadrilateral times (squeeze, up-slope, welding time, and hold) at three different levels were considered as Taguchi algorithm inputs. The results of Taguchi sensitivity analysis showed that the parameters of electrical current (22 %) and welding time (17 %) are the most effective factors on the nugget diameter. Next, Multiple Regression Technique (MRT) was used to present a new equation for calculating spot diameter via the process parameters. The findings of this study showed that the difference between FE results and MRT for predicting spot diameter is less than 13%. Eventually, Response Surface Method (RSM) was utilized to determine the interaction effects of process parameters on the spot weld quality.

2019

In this study, the experimental procedure of various welding processes has been explained and the variations in the various properties of weldment due to the influence of several welding parameters were studied. Here, the processes are common to all the conditions such as the welding conditions and material selection criterion. In the present paper, the focus is on presenting and classifying the specified welding process and the changes in the properties of weld in terms of varying parameters applied for welding process. This study allows putting them into proper context based on the new trends in the field of welding. Finally, the variations of the properties of weld with respect to various parameters, defects in weldment and stresses in weldment have been reviewed.

ADVANCEMENTS IN CIVIL ENGINEERING: COSMEC-2021

Background/Objectives: Fsw process that doesn't require the filler material for joining the pieces. However, it is well established that adding a filler material to several welding techniques increases weld grade, joint durability, and other constructional qualities. Methods/Statistical analysis: FSW is a modern technique which overcomes many demerits of conventional welding processes like generation of harmful gases and requirement of high energy input. TRS 800rpm, 1000rpm, or 1200rpm, and TTS 20, 30, or 40 (in mm/ min) are considered to see the effect on hardness of weld joints under Taguchi L9 and ANOVA. Findings: In research, using tool rotation speeds of 800rpm, 1000rpm, or 1200rpm & tts of 20, 30, or 40 (in mm/ min). As tool rotation speed is increased, the hardness is predicted to climb for 1200 rpm with 30 mm/ min. Design of Experiment has been prepared by Taguchi's orthogonal system which helps to take better results with optimum number of experiments. Improvements/Applications: FSW finds its applications in the field of manufacturing industry; like in ship building, aerospace, production of automobiles and used extensively in fabrication of aluminium plates/sheets, and materials like steel, magnesium.

IRJET, 2021

An attempt is made to develop the dissimilar metal plate welded joints by MIG welding process using Cu coated mild steel Filler wire. Dissimilar metal welding is used in various fields like chemical, petrochemical, nuclear, thermal power plant industries, automobile industries also in aeronautical engineering and marine industries. This paper deals with the analysis of mechanical properties at different parameters like welding current, voltage, and welding speed. In this trial, two metals Ms and stainless stee304 are used. So the main focus will be to improve the mechanical properties like hardness and tensile strength by UTM machine and Rockwell hardness testing machine. In this paper optimum value of current, voltage speed of weld speed is identified for the highest value of weld strength and BHN value which helps to predicts the strength of the proposed welded joint under the consideration of the applied field.

Welding input parameters play a very significant role in determining the quality of a weld joint. The joint quality can be defined in terms of properties such as weld-bead geometry, mechanical properties, and distortion. Generally, all welding processes are used with the aim of obtaining a welded joint with the desired weld-bead parameters, excellent mechanical properties with minimum distortion. Nowadays, application of Design of Experiment (DoE), Evolutionary algorithms and computational network are widely used to develop a mathematical relationship between the welding process input parameters and the output variables of the weld joint in order to determine the welding input parameters that lead to the desired weld quality. A comprehensive literature review of the application of these methods in the area of welding has been introduced herein. This review was classified according to the output features of the weld, i.e. bead geometry and mechanical properties of the welds.

Journal of Emerging Technologies and Innovative Research (JETIR), 2021

The systematic approach carried out towards the optimization on the joint of carbon steel and stainless steel SMAW welding. The quality of the welding is depended upon the various parameters which are used in welding. In current work by changing parameters like voltage, polarity and bevel angle, we can easily find the effect on weld joint which is made from carbon steel and stainless steel. The Levels of parameters derived from design of experiment procedure (DOE). The tensile specimen prepared as per the ASTM and tested on the universal testing machine. Response surface methodology has been used to develop the mathematical model for tensile strength. The effect of the different parameter on the tensile strength has been evaluated. The ultrasonic method has been used for finding internal defects like cracks, porosity, etc. The results indicated that electrode diameter current and bevel angle play vital role welding strength. The maximum strength has been achieved by using maximum electrode diameter and current, but bevel angle should be accurate. Very high and very low bevel angle may decreases welding strength.

The present paper deals with the tensile strength and Rockwell hardness of the weld joint optimised using Taguchi statistical approach. Gas Metal Arc Welding is carried out to create the weld joint between EN8 and Stainless Steel. Preheat temperature, Gas flow rate and Welding current are the parameters to be optimised. All the parameters are taken at 3 level and thus using degree of freedom, 9 set of experiments are carried out. Signal-to-noise ratio of each set of experiment is calculated and thus the optimised set of experiment in both cases, tensile strength and hardness of the joint, is evaluated. The final results exhibit a difference of 6% and 10% respectively for tensile strength and hardness from the measured values.