Resistance Spot Welding Research Papers (original) (raw)

The presentation shows the comparison of energy efficiency - types of welding machine versus electrode tip material composition since the energy efficiency may greatly impact to the welding process window / weldability Lobe, resulting to... more

- by
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- Robotic Spot Welding, Resistance Spot Welding, Resistant Spot Welding

Review on the spot weld analysis for strength using simulation was done from recent literature. Spot weld model practiced by automobile industry predicts the strength with 45.33% error. In this paper two spot weld models are studied and analysed to find best suitable for modelling of the spot weld. Hence it is necessary to perform modelling with minimum possible error to get optimum results. Various methods have been proposed by researchers which mainly considers properties of base material as input parameters. In fact heat affected zone has different mechanical properties from the base metal which must be considered for the simulation. Hence finite element analysis had been done on spot weld taking heat affected zone into account for simulation.

- by Swapnil Ahire
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- Resistance Spot Welding

New materials and production technologies demand improved non-destructive techniques for inspection and defect evaluation, especially when critical safety applications are involved. In this paper two Non-destructive Testing (NDT) applications are presented: the inspection of Friction Spot Welding (FSpW) of AA2024-T351 with and without Alclad™ and a composite material GLAss-REinforced Fibre Metal Laminate (GLARE®) with artificial defects. The two applications were tested by Eddy Currents (EC), using both conventional planar spiral probes and a new EC probe developed by some of the authors, called lOnic probe. Four different FSpW conditions were produced and tested in 2 mm-thick plates of duraluminium with and without Alclad™. Three defects were introduced in GLARE® aiming to compare the reliability of the different NDT approaches. The experimental results show that the lOnic probe is able to identify different levels of FSpW quality regions by a distinctive perturbation on the output signal, whereas conventional probe cannot distinguish the different FSpW conditions. Regarding the GLARE® application, it was found that lOnic probe can detect the deeper defect easier than the conventional EC probe.

- by Telmo G Santos
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- Engineering, Materials Characterisation, Friction Welding, Aluminium Alloys

This article shows the relationship between spot welding parameters namely weld force, weld current and weld time & how they are inter related in weld nugget formation. Graphical lobe curve is used as presentation for better... more

- by Mohd Rashidi Asari
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- Mechanical Engineering, Resistance Spot Welding, weldability lobe

The analytical modelling of the PbSb alloy resistance spot welding process has been developed on the basis of mathematical analysis of thermomechanical conservation laws. The numerical solution of partial differential equations, obtained by such modelling, has been achieved by the finite element method. Thermomechanical equilibrium equations are derived, including specific properties, typical for PbSb alloys. The paper utilizes the basic experimentally proven assumption, that the temperature fields govern all processes during welding. Full agreement is evident between the experimental and analytical data.

- by Zoran Radakovic and +1
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- Materials Science, Mathematical Modelling, Finite Elements, Resistance Spot Welding

Mathematical modelling / equations & references used to develop simulator of weldability Lobe for 2 or 3 panel combination of steel sheets in automotive industries

- by Mohd Rashidi Asari
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- Resistance Spot Welding

Among the different welding technologies, portable welding guns are one of the most critical devices in relation to human exposure to electromagnetic fields. This paper focuses on medium frequency direct current guns proposing two actions aimed to the mitigation of the magnetic field generated during the welding process. The first action consists in the adoption of a passive shield for the on-board medium frequency transformer. The analysis points out that the transformer alone produces a magnetic field that can exceed the prescribed limits. Therefore, a suitable mitigation system is identified. The second action aims to mitigate the predominant magnetic field that is generated by the electrodes of the welding gun. The analysis of the field waveforms shows that the rise time of the welding current pulse is the main parameter affecting the exposure index. The effect of the increase of the rise time is investigated through experimental and numerical analyses. The results prove that a small increase of the rise time causes a significant reduction of the exposure level. It is noteworthy that the two mitigation actions can be adopted on both existing and newly developed welding guns as they do not require any structural modification of the welding device.

- by ABRAHAM SILVA HERNANDEZ and +1
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- Welding Technology, Welding Metallurgy, Resistance Spot Welding

A methodology is described for determining the mechanical properties of the heat-affected zone (HAZ) in a resistance spot weld. To perform detailed finite-element analyses of spot weld overload failures, it is necessary to have the mechanical properties of the various HAZ subzones. To this end, simulated HAZ material samples were fabricated in a process that utilized a resistance spot welding

- by sachin kanubhai
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- Mechanical Engineering, Resistance Spot Welding

This article shows the impact of welding transformer and electrode tip on weld nugget formation in resistance spot welding (RSW). The impact is shown in weldability lobe, a graphical presentation of the acceptable welding parameters set that may results in acceptable weld quality. Understanding of welding equipment and its system is the key for welding parameters optimization process in selecting the best welding parameters that meeting design specification at minimum cost.

Resistance Spot welding (RSW) is one of the common welding processes used for sheet joining especially in the automobile and aerospace industry. It is used in a wide range of industries but notably for the assembly of sheet steel vehicle bodies. This is a type of resistance welding where the spot welds are made at regular intervals on overlapping sheets of metal. Spot welding is primarily used for joining parts that are normally up to 3 mm in thickness. The joint quality can be defined in terms of properties such as weld-bead geometry, mechanical properties and distortion.The objective of the research is to determine the optimum combination of parameters responsible for better quality of joints. The complicated behavior of the process must be analyzed to set the optimum parameters to get the optimum weld quality. The paper also presents the FEA simulation of the RSW process.

- by Hamid Taghipour Armaki
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- Soldering, Welding, Bending, Resistance Spot Welding

The engineering parts joining by the spot welding require acceptable properties to survive the loading conditions. Several studies show that the welding variables have an effect on the properties of spot nugget and on the future cracking. This review summarizes the resistance spot welding process (RSW). It introduces the basic spot welding principles, experiments, limitation and defects. The new concepts and awareness were presented. The results from the series of scientific works and literature are discussed. The metal’s weldability, strength, and fracture are the main topics in several structural analysis. The welding variables effect on the mechanical properties and performance of the structures is the key analysis. In general, the increasing of the heat input by adjusting the current, time, and pressure producing higher weld area in turn enhance the toughness. However, by increasing the weld area, the defects and cracking tend to appear. Hence, a desired weld size with the mechanical properties is required. The nugget fracture mode is changing from plug or button tearing to shear failure mode depending on the weld properties. The crack grows either from the internal defects or around the nugget.

- by A.M. Al-Mukhtar
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- Fracture, Welding Technology, Welding Engineering, Automotive Industry

Variation in dynamic contact resistance with the change in welding process parameters such as weld current , weld time and electrode force were taken into account for establishing the range of adequate nugget formation parameters. Influence of the welding process parameters on the shear – tensile strength, nugget diameter and the observed failure mode was analysed. The adequate resistance spot welding process parameters for galvannealed high strength interstitial free steel sheets of 1.6 mm thickness were estimated as 8 kA weld current, 250 ms weld time and 3.5 kN electrode force. Increase in the mean dynamic contact resistance led to a significant reduction in nugget diameter. A critical nugget diameter distinguishing between the IF and PF mode was experimentally determined by failure mode analysis. Different numerical models for estimation of critical nugget diameter were evaluated.

- by SHRAVAN SINGH RAO and +1
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- Welding Technology, Welding Engineering, Resistance Spot Welding

In this study, the microstructural characterisation, mechanical testing and fractography investigation were performed on twinning induced plasticity (TWIP) steels, fabricated with resistance spot welding. Failure mode during the cross-tensile test was found to follow the sequences of strain localisation of both sheets, crack initiation at notch tip, crack following along the fusion boundary and, finally, ductile shear fracture along the sheet thickness direction. On the other hand, failure in the tensile shear test was always directed along the sheet/sheet (s/s) interface; the interfacial failure and shear deformation were observed at the weld centreline. Solidification occurred as a primary austenitic solidification mode, and no martensitic transformations were detected through electron backscatter diffraction analysis. The fusion zone was mainly composed of austenite with directional solidification towards the centreline; the columnar dendritic and equiaxed structures were identified. Interdendritic C and Mn cosegregation were confirmed by electron probe microanalysis.

- by Dulal Saha, PhD.
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- Microstructure, Segregation, Resistance Spot Welding, Fractography
- by Noman Khandoker and +1
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- Mechanical Engineering, Finite Element Analysis (Engineering), Resistance Spot Welding

En el marco de las modernas democracias, una de las partidas presupuestarias más amplias de las campañas electorales es la dedicada a la realización y producción de spots electorales. Igualmente, el empleo de estas piezas audiovisuales se ha generalizado hasta el punto de no haber campaña de relevancia que no desarrolle uno o varios spots tanto para televisión como para los nuevos medios digitales. El poder persuasivo de los anuncios descansa, en gran medida, en las estrategias discursivas del montaje audiovisual, que son, a su vez, herederas del cine de propaganda.
Se propone un método específico de análisis plano a plano, centrado en todos los elementos que toman partido en el engranaje de los montajes audiovisuales: desde la forma de la imagen hasta la retórica de la construcción audiovisual. Igualmente, se aporta una metodología concreta que permite el análisis comparativo de unos spots con otros, y de campañas completas unas con otras, independientemente del contexto geopolítico, en función de datos racionalizados estadísticamente. Un método, en suma, que busca aunar la especificidad del comentario de texto cinematográfico y del análisis retórico publicitario con las más avanzadas tecnologías informáticas.

A study was carried out to investigate the effect of governing metal thickness (GMT) and stack orientation on weld quality and mechanical behaviour of resistance spot welded (RSW) AA5754 aluminium. Individual samples from 27 different joint stacks in three test geometries; lap-shear, coach-peel and cross-tension were evaluated for quasi-static and fatigue performance; micro examination was also conducted on some of the samples to assess weld quality. The results derived from over 1000 samples show that: the GMT has a significant effect on welding quality by controlling progression of weld nugget from under-developed to over penetrated. The GMT also determines the feasible quasi-static joint strength regardless of stacks in the three joint geometries tested, though the effect differs with respect to test geometry. The fatigue behaviour is dominated by the effect of GMT on attainable weld size, overall joint stiffness and stress concentration, providing good quality of weld nuggets is...

- by Dezhi Li
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- Materials Design, Resistance Spot Welding, Stress Concentration

The present work deals with the optimization of welding process variables by using Tungsten inert gas welding. In this process input variables are voltage (V), current (I) and welding speed (S) with tensile strength and hardness as responses of low carbon steel (ASTM A29). The investigation is based on Taguchi approach [L 9 ], using Analysis of variance (ANOVA) to determine the influence of parameters with the optimal condition. Finally, the confirmation test has been carried out to compare the predicted value of tensile strength and hardness with the experimental value.

- by siva raju and +1
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- Optimization method using Taguchi Method, Resistance Spot Welding, ASTM Testing of Materials

Resistance spot welding is one of the oldest of the electric welding processes in use by industries today. The weld is made by a combination of heat, pressure, and time. As the name resistance welding implies, it is the resistance of the material to be welded to current flow that causes a localized heating in the part. Resistance spot welding is mostly used to weld various sheet metal products. Typically the sheets are in the 0.5-3.0 mm thickness range. The resistance spot welding of dissimilar materials is generally more challenging than that of similar materials due to differences in the physical, chemical and mechanical properties of the base metals. The influence of the primary welding parameters affects the heat input such as, peak current on the morphology, micro hardness and tensile shear load bearing capacity of weldment. Database regarding dissimilar materials resistance spot welding is very limited hence much research work is going on this field by various researchers, but most of work is on low thickness material typically 1mm to 2 mm. This work is an attempt to reveals aspects of the resistance spot welding of dissimilar materials of higher thickness typically 3mm. In this work resistance spot welding is performed on two different metal steels named low carbon steel, high strength low alloy steel with variation in current rating keeping of the parameters as constant. Although the bearing force of joint shows a linear relation with current rating but at higher current rating poor joint appearance is obtained also cavities are formed in joint.

- by IJRASET Publication
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- Resistance Spot Welding
- by Naresh Kumar
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- Condensed Matter Physics, Cleaner Production, Painting, Refrigeration

In this work, the effects of the coating composition and the welding parameters on the heat generation and nugget formation during resistance spot welding of the hot press forming steels have been evaluated. Two types of coated steels were used, termed as Al–Si and Zn coating. Al–Si coated steel showed rapid nugget growth toward the electrode direction, which is the probable reason of the higher heat conduction from the electrode–sheet surface toward the bulk material. In Zn coated steel, heat was generated and localised at the faying interface and uniformly propagated to the steel substrate. High speed camera images showed that the presence of oxide at faying interface provides inhomogeneous current flow and violent heat generation in the Zn coated steel.

- by Yeong-do Park and +1
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- Resistance Spot Welding, High Speed camera, Multi Layer Coatings, Hot Press Forming
- by Mohammad Khaleel
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- Mechanical Engineering, Civil Engineering, Aerospace Engineering, Strain Rate

In this paper, resistance spot weldability of high-Mn steels were investigated in order to get high reliability in welded joints of automotive components. Microstructural characterizations, cross-tensile test (CTT), microhardness tests of spot welded parts were conducted. The effects of weld current on the microstructural characteristics, mechanical properties, and fracture modes were investigated using optical microscopy (OM) and scanning electron microscopy (SEM). The hardness in the weld nugget was observed to be lower than that in the base metal (BM). In CTT, the failure initiation was observed to occur at the boundary of the weld nugget. Also welding imperfections of welded parts were investigated. Liquation cracking in heat affected zone (HAZ), porosity, and shrinkage cavity were found most common welding defects in welded parts. Furthermore, the effects of welding imperfections on weld quality and failure criteria were identified and discussed.

- by Yeong-do Park and +1
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- Microstructure, Weldability, Resistance Spot Welding, HAZ Liquation Crack
- by Ivan Santana
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- Materials Engineering, Mechanical Engineering, High Frequency, Simulation

S. Smith, N.J. den Uijl, T. van der Veldt, T. Okada, M. Uchihara, F. Fukui. The effect of ageing on the spot weld strength of AHSS and the consequences for testing procedures, IIW-1976-08, Welding in the World, p.p. R12 – R26, Vol. 54,... more

Uijl, NJ den, Smith, S, Nishibata, H, Okada, T, Uchihara, M & Fukui, K (2008). Prediction of post weld hardness of advanced high strength steels for automotive application using a dedicated carbon equivalent number. IIW-1873-07. Welding... more

- by Nick J den Uijl
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- Welding Technology, Welding Engineering, Automotive Industry, Welding and Joining

Uijl, NJ den (2006). Modelling the influence of resistance spot welding on material properties. In W. Lucas & V.I. Makhnenko (Eds.), Proc. Joint Int. Conf. "16th Int. Conf. Computer Technology in Welding and Manufacturing" and "3rd Int. Conf. Mathematical Modelling and Information Technologies in Welding and Related Processes" (pp. 306-313). Kiev, Ukraine: E.O. Paton Electric Welding Institute of the NAS.

N. den Uijl, T. Okada, T. Moolevliet, A. Mennes, E. van der Aa, M. Uchihara, S. Smith, H. Nishibata, K. Fukui: IIW-2162-11 (III-1573-10) Performance of resistance spot welded joints in advanced high strength steel in static and dynamic... more

- by Tim Frech
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- Engineering, Process Control, Process Monitoring, Low Noise Measurement Systems

Resistance Spot Welding (RSW) is an important welding technology for joining two or more metals in various manufacturing
industries. For instance, to date a car may contain an average of 3000-4000 spot weld joints and the nuggets’ joints are very
important between metal sheets to ensure the aging factor of mechanical assemblies. As such the growths of spot welds create
significance and it is determined by its’ main controlling parameters such as: current, weld time and force. However factors
such as electrode deformation, dissimilar materials, materials with different thicknesses and corrosions are also affect weld
growth. This study was conducted to look into the effects of different thickness (1 mm and 2 mm) on weld nugget growth of
mild steel. The tensile test and hardness test have been carried out to characterise the formation of weld nugget growth for
different weld schedules. The results of the experiments showed that the growth of spot weld nuggets was affected by different
thicknesses. The microstructures of weld nuggets have also shown distinguishable differences in weld growth for the both 1
mm and 2 mm thicknesses. The results have shown difference in yield strength as well, for the same welding schedules. This
was happened due to the difference of resistive path of two thicknesses.

- by Nachimani Charde
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- Resistance Spot Welding

The specimens of thickness 0.8 mm carbon steel number 1.8902 in a strip form were welded. The strips of lap joints and curved peeljoints configurations have been welded. The welding parameters such as weld current and weld time have been investigated. The relation between the weld area and the joint strength properties has been presented. The obtained results were showing that the weld joint strength and the molten area (weld nugget volume) highly increase with the increasing of weld current. Therefore, the correlation between the maximum load (joint strength) and area has been given. The reliable weldability under the tensile and shearing loading was considered. Therefore, the new limits of weldability have been presented to consider these two types of loading. Moreover, the experimental results were compared with the empirical relations that consider the sheet thickness only.

- by A.M. Al-Mukhtar
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- Steel Structure, Fracture Mechanics, Welding and Joining, Resistance Spot Welding
- by Beno Klopcic
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- Engineering, Welding, Physical sciences, Magnetic Properties