EFFECT OF WELDING PROCESS PARAMETERS ON TENSILE OF LOW CARBON STEEL 283 G.C

In this study, three welding methods are used. The purpose to investigation the effects of SMAW, SAW, and gas tungsten arc welding (GTAW) on the tensile stress of low carbon steel conforming to ASTM 283 c. 8mm thick plates are used as base material for butt welded joints. The tensile properties of the welded joints were evaluated and the results were compared by experts using the Taguchi method to design three levels of each parameter (current, voltage and displacement speed). From this research, it is found that compared to metal shielded arc welding and submerged arc welding, the pulling effect of the gas shielded welding joint of the tungsten electrode is the best. This is mainly due to the presence of The results of using analysis of variance (ANOVA) to estimate important parameters show that welding current and speed of the weld have a significant effect on tensile stress .the experimental results are in agreement with predicted results, and the maximum error is 3%..

Process Parameters Optimization for GMA Welding of AISI 1008 Steel Joints for Optimal Tensile Strength

Parameters optimization has become a gateway to achieving quality welds with improved properties desirable for construction and industrial applications. The complex interaction of welding input parameters requires process optimization to achieve optimal responses (s). This study reports the optimization of input parameters for Gas Metal Arc Welding (GMAW) for optimal ultimate tensile strength in AISI 1008 steel joints. Three levels of arc voltage, welding current, and gas flow rate were selected as input parameters, while the targeted output response is the ultimate tensile strength. Taguchi’s method with an L-9 orthogonal matrix was adopted for the process optimization. The MINITAB 17 software was used to analyze the response through analysis of variance and signal-to-noise ratio. The result revealed that the parameter settings for optimal tensile strength for the GMA welding of 6 mm thick AISI 1008 steel joint are arc voltage set at 30 V, current at 180 A, and gas flow rate set at 17 L/mm. The analysis of variance showed that the arc voltage had the most significant influence on the ultimate tensile strength with a 39.76% contribution, followed by the gas flow rate with 31.15%, while the welding current had 6.28% contributions. The surface plots show that a lower-level voltage, higher-level welding current, and higher-level gas flow rate favoured maximum ultimate tensile strength.

OPTIMALISASI PARAMATER RESISTANCE SPOT WELDING UNTUK PENGELASAN TIGA TUMPUK LEMBAR BAJA SPCC

In the automotive industry, the latest breakthroughs and innovations are strongly influenced bymaintaining and increasing production results so that the use and application of technology is anabsolute must, as is welding technology. Thin sheet-shaped components are found in many car bodies.One of the methods used in joining plate sheets is to use the resistance spot welding method, which is awelding process that is only carried out at a certain point using copper electrodes. In the welding method,maintaining quality in order to produce products and services that can meet the needs and expectationsof consumers related to the product's life time or service. SPCC steel (Cold Roller Stell Sheet) is one ofthe most widely used materials in car body welding applications. The characteristics and mechanicalproperties of SPCC steel from the results of the three-sheet welding were examined using the parametersof welding current, welding time, welding distance. The results showed that the increase in current wouldaffect the diameter of the electrode traces and the nuggets that were formed. The greater the current used,the larger the diameter of the trail, so that the optimum pull-shear load is at a current of 6.5 kA at adistance of 20mm with a value of 365.53 MPa, also the highest hardness value is in the nugget area witha hardness value of 595, 14 HVN at a current of 6.5 kA and from the results of measuring grain diameterin microstructural testing for the HAZ area the best at a welding current of 6.5 kA. Because the smallerthe weld grain diameter, the greater the strength of the weld joint. Then the data from the results of theshear-shear test are analyzed using the Taguchi method, and the most effective parameters in the tensilesheartest with a combination of A (6.5) B (1.5) C (15) and from the experimental results for tensile loads.slide obtained 397 MPa.

SMAW: The Effects of Currents and Welding Rod Diameters on Welded Joint Ultimate Tensile Strength Using the Full Factorial DOE

This research was significant as it extensively studies the effects of current and rod diameter on SMAW welded join. The Mild Steel (AISI 1018) was used as the base material to be welded using the E-6013 welding rod. The experiment was constructed according to the full factorial design of experiment (DOE). This project found that the current and rod diameter are the significant factors in affecting the ultimate tensile strength (UTS). New contribution from this research was that the rod diameter is more significant than the current in affecting the UTS of a welded joint. In addition, this research also contributed new finding by showing that the interaction between current and rod diameter as significant in affecting the UTS. This interaction was also found to be more significant that current but less significant than rod diameter in affecting the UTS of welded joint. In addition, this research showed that the tensile strength increases when the current is increased from 80A to 100A. However, the tensile strength decreased as the current is set between 110A to 130A. At the same time, the welding rod diameter of 2.5mm produced the highest tensile strength compared to 3.2mm and 4.0mm rod diameter. This research also optimised the experiment and found that the highest tensile strength obtained is 342.39 MPa, which is produced using 80A of welding current with 2.5mm rod diameter.

Robust Parameter Design of Shielded Metal Arc Welding (SMAW) for Optimum Tensile Strength

Shielded Metal Arc Welding (SMAW), an arc welding process, is widely used in applications. In practice, SMAW is widely applied to the welding process on hollow square pipe. Performance expected from this welding is the tensile strength of weld joint. The tensile strength is influenced by parameters process which have possibility for an optimization process to become ‘robust’. Robust is a design which less sensitive to the effect of uncertain quantities or noise factors. Taguchi method is the most efficient optimization method which accommodates the noise factors effect and requires less experiment. This study is focusing on optimizing the welding process on hollow square pipe. Parameters process such as welding current (I), electrode angle (θ), root gap (d) and electrode type (E) are adopted as parameters design. Taguchi method are chosen as a strategy and L9 fractional orthogonal array are chosen as the design experiment, which only 9 experiment samples needed from 81 experiments that should have been carried out for full factorial design. The objectivity is to maximize the tensile strength of weld joint. Three replications of L9 fractional orthogonal array Taguchi had been performed to generate the tensile strength and estimates the fluctuation of the output caused by noise factors. This study found that the welding current of 100A (I), electrode angle (θ) of 90°, root gap (d) of 2 mm, and electrode type (E) of E7018 produce the optimum results. Tensile strength improved from this robust parameter design is about 98.39 MPa based on initial parameter design.

Resistance spot welding of a thin 0.7 mm EN10130: DC04 material onto a thicker 2.4 mm 817M40 engineering steel

The effects of welding current, electrode force, and welding time in a resistance spot weld were studied to investigate the effectiveness of welded joints between a thin EN10130: DC04 material and a thicker 817M40 part, through analysis of the microstructural and mechanical properties. All welded specimens were subjected to tensile testing at room temperature (25°C) and sub-zero temperature (-46°C) to test the strength of the welded joints. No full button failure was observed at either room temperature or sub-zero temperature after optimization of the weldng parameters. The fusion zone was observed to consist mainly of martensitic phase, due to rapid quenching, while the HAZ was composed of clusters of martensite in a ferrite and bainite matrix. The base 817M40 metal remained fully ferritic after welding. The hardness was found to increase with increasing welding current. An increase in nugget size, indicating good fusion of the weld, was observed with an increase in the welding current.

Fractographic Analysis of GTAW Robotic Welded Joints Fractured under Stress in Experimental HSLA Cr-Ni Steel

The welding current (A), arc voltage (V) preheating (°C), travel speed (mm·min-1) and net heat input (Qnet) were evaluated, on the strength and morphology of the fracture in experimental HSLA Cr-Ni steel welded joints, with commercial (ERS70S-6) filler metal and robotic GTAW technique. The samples were characterized by uniaxial stress tests, stereoscopy and Digital Image Processing (DIP). The results showed that the resistance to fracture of the experimental steel was exceeded by 18.39% by applying Qnet 0.520 (kJ·mm-1) and the combination of: 200 A, 12.7 V, 25 °C and 180 mm min-1, which influenced the ductile fracture morphology and topology. While the low Qnet (0.200-0.208 kJ·mm-1) favors instantaneous deformation of the welded joints with fracture in the weld bead as the major defect.

Arc Welding-Laser Shock Forging Process for Improving the Mechanical Properties of the Fe-Cr-C Cladded Layer

While parts can be repaired via arc welding (AW), it is usually necessary to add some types of excitation method to improve the mechanical properties of the cladded layer. Here, the arc welding-laser shock forging (AW-LSF) was used to repair Q235 steel pipes (Fe-Cr-C alloy was used as the cladding material). The effects of the welding current (WC), welding speed (WS), and laser shock frequency (LSF) on the geometry and microhardness of the weld bead were studied. The AW-LSF and AW repair processes were compared. The results demonstrate that the bead width (W) and penetration depth (D) increase with the WC, while the weld height (H) decreases with the WC. The H, W, and D all decrease with the WS; W and D increase with the LSF; and H decreases with the LSF. As the WC increases, the hardness of the fusion zone (FZ) and partial fusion zone (PFZ) decreases significantly, while the hardness of the heat-affected zone (HAZ) remains nearly unchanged. As the WS increases, the hardness of the PFZ decreases, while the hardness of the FZ and HAZ remains nearly unchanged. With the increase of the LSF, the hardness of the PFZ, FZ, and HAZ increases. Compared with AW, the AW-LSF can reduce the cladded layer crystal grain size, increase the hardness, and improve the sliding wear resistance.