Improvement in the Design of Welded Joints of EN 235JR Low Carbon Steel by Multiple Response Surface Methodology

Abstract

Gas metal arc welding (GMAW) is a joining process that is controlled by several inputs or welding parameters. However, speed, current and voltage are the parameters that are most frequently used in setting this process. Cord area, yield stress, tensile strength, residual stresses, hardness and roughness are considered to be outputs or welded joints parameters. They are widely used when the design requirements are based on the cost, manufacturing speed, strength and surface finish. This paper seeks to determine the relationship between the welding parameters and the welded joint parameters of speed, current and voltage in butt joints (X-groove) of EN 235JR by the response surface method (RSM). The optimal joints when considering the design requirements of cost, manufacturing speed, strength and surface finish were achieved by using the multi-response surface (MRS). The optimal welding parameters reached when considering the design requirements of cost were 140.593 amps, 8.192 mm/s and 29.999 volts, respectively, whereas the design requirements of manufacturing speed were 149.88 amps, 9.261 mm/s and 29.999 volts. Finally, the welding parameters for the design requirements of joint strength and surface finish were 149.086 amps, 7.139 mm/s and 28.541 volts and 150.372 amps, 8.561 mm/s and 29.877 volts, respectively.

Using Genetic Algorithms with Multi-Objective Optimization to Adjust Finite Element Models of Welded Joints

“…Table 3 shows the range of values that were considered for each of the input parameters of the FE models studied to generate the 100 individuals. The range was the same for each of the three welded joints FE models studied and was based on experience that was gained in previous research work [11,19,20]. Table 4 shows the results of using the CFS technique to analyze the relationship between the output feature and "objective function J Totalj " for each of the three FE models of welded joints proposed, and the 13 inputs parameters.…”

“…The wire for each study specimen was an ER70S-6 of 1.2 mm diameter and with mechanical behavior and a chemical composition that was similar to that of the base metal. The selection of the ranges for current and voltage, as well as the electrode orientation, shielding gas flow rate, distance between nozzle and plate, and speed at 80 • , 20.0 L/min, 4.0 mm, and 6.0 mm/s, respectively, was based on previous studies [19] to avoid defects or complex problems in the welded joint FE models that were studied. These defects are: pores in weld beads, fusion of the plates to be welded, excessively small weld beads that do not completely cover the mechanized zone of the plates, thereby creating the Butt joint single V-groove weld, or excessively large weld beads.…”

Coagulation: Determination of Key Operating Parameters by Multi-Response Surface Methodology Using Desirability Functions

“…RSM was developed initially to model experimental responses. However, it has found use in optimizing industrial processes and products [39,40]. RSM often appears as a series of statistical techniques that require a regression model that depends on a low-degree polynomial function (Equation (1)):…”

An Improvement in Biodiesel Production from Waste Cooking Oil by Applying Thought Multi-Response Surface Methodology Using Desirability Functions

“…Box and Wilson introduced it in 1951 [16] for experimental data that were gathered to provide a model or optimal response. RSM was developed originally to model experimental responses, but has been used with other techniques to optimize industrial processes and products [17,18]. Essentially, RSM consists of a collection of statistical techniques that use a regression model that relies on a low-degree polynomial function (Equation (1)):…”