Print ISSN: 1681-6900

Online ISSN: 2412-0758

Keywords : DOE


Study of Mechanical Properties of Carbon Steel Plate SA-516 Gr. 70 Welded by SAW Using V-Shape Joint Design

Samir A. Amin; Mohannad Y. Hanna; Abdulaziz S. Khider

Engineering and Technology Journal, 2020, Volume 38, Issue 2, Pages 152-165
DOI: 10.30684/etj.v38i2A.269

Submerged arc welding (SAW) is a fusion type welding and it is considered one of the most important welding types due to its inherent capabilities of high welding speed, high deposition rate, welding large thickness plates owing to its deep penetration characteristic and many other advantages. In this study, the goal was to investigate the effect of welding parameters, namely (welding current and welding speed) as well as the joint design on the mechanical properties (yield stress, bending force on the face of the weldment and hardness of the weld metal. Experiments were conducted employing Design of Expert (DOE) software and Response Surface Methodology (RSM) technique. The experiments were conducted by welding ASME SA-516 Gr. 70 steel plate with dimension (300 mm × 150 mm × 10 mm) depending upon the design matrix developed via the DOE. Results manifested that the optimum process parameters for maximum yield stress, maximum bending force and minimum hardness were at (425 amps) welding current and (35 cm/min) welding speed, where the arc voltage was held constant at (37 volts). The optimum values for the yield stress, bending force and hardness were (474.447 MPa, 36.997 kN and 150 HV), respectively. Finally, it was found that the predicted and experimental results of yield stress, bending force and hardness agree very well according to the ultimate error (1.05%, 1.92%, and 4.25 %), respectively.

Optimization the Resistance Spot Welding Parameters of Austenitic Stainless Steel and Aluminum Alloy Using Design of Experiment Method

Sabah Khammass Hussein; Osamah Sabah Barrak

Engineering and Technology Journal, 2016, Volume 34, Issue 7, Pages 1383-1401

This research aims to study the effect of RSW parameters on the sheerforce of the spot weldedfor two materials {AISI 304L and AA 6061-T6}with (0.5 and 0.7 mm) thickness. Three values for each welding parameters (welding current, electrode force, squeeze time and welding time) are to be used. The effect of those parameters has been analyzed by using design of experiments (DOE) in order to determine and reduce the number of the tested specimens.
The experimental tests have been donethat are;shear, micro hardness tests and microstructure examination. It was found that the maximum shear force in welding of similar material AISI 304L is (F = 4.78 KN for t = 0.7 mm), while in the joint of dissimilar material (AA 6061-T6 with AISI 304L), the maximum shear force is (F = 1.42 KN for t = 0.7 mm). These values have been optimized to reach (F =5.13 KN & F =1.54 KN) respectively by using DOE. The minimum shear force was (F = 0.07 KN in t = 0.5 mm).
It was found that, increasing the welding current and sheet thickness gave an increase in the shear force, but at the same time the reduction in shear force has occurred during the increasing in electrode force, squeeze time and welding time. From micro hardness tests, it was found that the maximum value of hardness was at the center of nugget zone (NZ) and it reduces slightly until reaching constant values away from nugget zone.

Analysis and Optimization of Resistance Spot Welding Parameter of Dissimilar Metals Mild Steel and Aluminum Using Design of Experiment Method

Sabah Khammass Hussein

Engineering and Technology Journal, 2015, Volume 33, Issue 8, Pages 1999-1011

This research aims to study the effect of parameters of the resistance spot welding (RSW) on the shear strength of the spot weld for different metals {AA 6061-T6and AISI 1010}using (0.5 and 0.7 mm) thickness.Three values for each welding parameters (welding current, electrode force, squeeze time and welding time) are to be used. The effect of those parameters have been analyzed by Minitab program by design of experiments (DOE) in order to determine and reduce the number of specimens required to achieve the tests. The design of experiment method which used was Taguchi method
The experimental tests that had been done are shear, Microhardness and microstructure tests.It was found that the maximum shear force in welding of dissimilar metals(AA 6061-T6 with AISI 1010)is (F = 1.14 KN for t = 0.7 mm ).This value has been optimized to reach (F =1.24KN) using DOE. The minimum shear force was(F = 0.25 KN in t = 0.5 mm).
In general, increasing the welding current and sample thickness gave an increase in the shear force, but at the same time the reduction in shear force have occurred during the increasing in electrode force, squeeze time and welding time.From Microhardness tests, the maximum value of hardness is found at the center of nugget zone (NZ) and it reduces slightly until reaching constant values away from NZ.