Weld Material Research Articles

Magnetic Pulse Powder Compaction

Powder metallurgy (PM) offers several advantages over conventional melt metallurgy, including improved homogeneity, fine grain size, and pseudo-alloying capabilities. Transitioning from conventional methods to PM can result in significant enhancements in material properties and production efficiency by eliminating unnecessary process steps. Dynamic compaction techniques, such as impulse and explosive compaction, aim to achieve higher powder density without requiring sintering, further improving PM efficiency. Among these techniques, magnetic pulse compaction (MPC) has gained notable interest due to its unique process mechanics and distinct advantages. MPC utilizes the rapid discharge of energy stored in capacitors to generate a pulsed electromagnetic field, which accelerates a tool to compress the powder. This high-speed process is particularly well-suited for compacting complex geometries and finds extensive application in industries such as powder metallurgy, welding, die forging, and advanced material manufacturing. This paper provides an overview of recent advancements and applications of MPC technology, highlighting its capabilities and potential for broader integration into modern manufacturing processes.

Quantitative non-destructive evaluation analysis and characterisation of microcrack detection based on carbon steel weld under alternating current field measurement

ABSTRACT Nondestructive testing of microcrack in welding seams is a key and challenging task in nuclear industry to evaluate material properties. The real magnetic characteristics of welds and stress redistribution have not been considered in the previous numerical simulation of welds and base metal materials, which leads to conservative calculation values and fails to meet actual engineering expectations. In this work, based on the difference between weld and base material structure, a non-uniform weld magnetic charge model was established and the stress distribution characteristics of weld cracks were analysed. The characteristics and gradient distribution of magnetic signals at weld and weld crack are calculated. The work quantitatively studied and characterised the influence of the offset weld position of the detection probe, the distance between the crack and the probe, the crack cluster, and the crack at the interface between the weld and the base metal on the detection signal. The microcrack detection of base metal, weld, and interface under various working conditions was compared and analysed. The difficulty of the AC electromagnetic method in weld inspection is solved, and the weld microcrack identification is realised. The results provide theoretical guidance for the identification of potential weld microcracks in spent fuel pools.

Solid-state welding of UFG copper rods with conical face by means of friction heat impulse

Abstract Solid-state friction welding of ultra-fine grained materials (UFG) is a complex process to implement. Exceeding the recrystallization temperature during the process causes degradation of the material’s properties. The process temperature can be reduced by limiting the heat power. Using standard friction welding machines and parameters, it is difficult to achieve an appropriately low heat power. The welding tests of Cu-ETP copper with an UFG structure were carried out on a prototype rotary friction welding machine. It enables welding materials with extremely short friction times and high pressure forces. A given set of non-standard/sharp parameters influences the generated heat power. Its characteristic course is called the friction heat impulse (FHI). The use of FHI allows the energy to be reduced to the minimum necessary to obtain a joint. In order to obtain better joint conditions in a short welding time, a conical surface was used on one of the welded samples. The friction welding tests carried out using the FHI method and a prototype machine showed that the average hardness value of the joints increased slightly from 129 HV0.2 to 130 HV0.2. Additionally, the tensile strength remained at the same level as the UFG base material. The results proved that it is possible to weld UFG copper rods with conical face under recrystallization temperature without any signs of degradation of the UFG structure.

Influence of the Oscillation Parameters Amplitude and Frequency on the Microstructure of Laser-Welded Thin Nitinol Foils

Laser welding has become well established for joining Ni-Ti-based shape memory alloys and extends the manufacturability of highly functional components with complex geometries. Published studies on the effect of laser welding on alterations to microstructure and properties of these alloys, however, mainly deal with conventional component dimensions and linear laser beam movement. In view of the increasing importance of microtechnology, research into joining of thin-walled Ni-Ti components is therefore of interest. At the same time, studies comparing oscillating and linear beam movement on other materials and the authors’ own work on Ni-Ti materials suggest that oscillating beam movement has a more favorable effect on alterations in material properties and microstructure. Therefore, laser welding of foils made of Ni55/Ti45 with 125 µm thickness was systematically analyzed using a fiber laser and circular oscillation. Amplitude A and frequency f were varied from 0 to 200 µm and 0 to 2000 Hz, respectively. Microstructural analysis showed that by increasing the frequency, grain refinement could be achieved up to a certain value of f. An increasing amplitude led to decreasing hardness values of the weld seam, while the influence of f was less pronounced. The analysis of the weld material using chip calorimetry (Flash DSC) revealed that the beam oscillation had fewer effects on the change in transformation points compared to a linear beam movement.

EXPERIMENTAL STUDY THE MECHANICAL PROPERTIES OF GMAW WELDING RESULTS ON S355J2+N MATERIAL WITH POST WELD HEAT TREATMENT (PWHT)

Assembly underframe trains are a connecting process part-part into a system that has a unified function, the process of which uses GMAW-type welding. From the welding results, there is potential for the formation of residual stress which is a problem in this research, so it is minimized using the method Post Weld Heat Treatment (PWHT) thermal. The research aims to determine and analyze the effect of PWHT on the mechanical properties and microstructure of low-carbon steel type S355J2+N resulting from GMAW welding. The research method uses experiments with PWHT temperatures at 450 °C, 750 °C, and non-PWHT to find out the mechanical properties of materials, use the tensile test and micro-Vickers hardness test. Meanwhile, to determine the microstructure formed is used micro examination. The test results, were compared between the welding material with PWHT and the welding material non-PWHT. The results of the research are that the largest tensile strength value of 576 MPa was produced in the material using PWHT at a temperature of 450 °C, the largest elongation of 34.85% was produced in the material with a PWHT temperature of 750 °C, and the highest hardness value was 207.44 HV in the material non-PWHT. The conclusion of the research shows that with increasing PWHT temperature, the hardness and tensile strength values of the material decrease, and there is an increase in the ductility value of the material which is influenced by changes in the dominance of ferrite and pearlite in the material.

PENGARUH JENIS WELDING GROOVE TERHADAP KEKUATAN IMPACT PLAT BAJA ASTM A36 MENGGUNAKAN MESIN LAS SMAW

Currently, metal joining with welding process is increasingly used, both in building construction, piping, and machine construction. This is due to the many advantages obtained from joining by welding. The use of the right welding groove will also affect the welding results. The purpose of using welding groove is for the place to fill the welding material and can also strengthen the design of the metal joint. Welding groove plays an important role in improving the design and properties of the joint in the welding process. ASTM A36 welding using SMAW welding current 110 A is carried out with Groove variations, namely VGroove, Square Groove, and Bevel Groove and using E6013 electrodes with a diameter of 2.6 mm. The purpose of this study was to determine the strength of SMAW welding joints on ASTM A36 against the Charphy impact test. the required impact charphy effort results (W) are on V Groove of 73.519 J, Square Groove of 67.43 J, and Bevel Groove of 70.485 J. And produces an impact charphy value (K) on V Groove of 0.918 J / ????????2, on Square Groove of 0.842 J / ????????2 and on Bevel Groove of 0.881 J / ????????2. The impact charphy value on V Groove with SMAW welding current of 110 A on ASTM A36 carbon steel is the best with the required impact charphy results (W) namely on V Groove of 73.519 J and the impact charphy value (K) on V Groove of 0.918 J / ????????2

PENGARUH JENIS WELDING GROOVE TERHADAP KEKUATAN IMPACT PLAT BAJA ASTM A36 MENGGUNAKAN MESIN LAS SMAW

Currently, metal joining with welding process is increasingly used, both in building construction, piping, and machine construction. This is due to the many advantages obtained from joining by welding. The use of the right welding groove will also affect the welding results. The purpose of using welding groove is for the place to fill the welding material and can also strengthen the design of the metal joint. Welding groove plays an important role in improving the design and properties of the joint in the welding process. ASTM A36 welding using SMAW welding current 110 A is carried out with Groove variations, namely VGroove, Square Groove, and Bevel Groove and using E6013 electrodes with a diameter of 2.6 mm. The purpose of this study was to determine the strength of SMAW welding joints on ASTM A36 against the Charphy impact test. the required impact charphy effort results (W) are on V Groove of 73.519 J, Square Groove of 67.43 J, and Bevel Groove of 70.485 J. And produces an impact charphy value (K) on V Groove of 0.918 J / ????????2, on Square Groove of 0.842 J / ????????2 and on Bevel Groove of 0.881 J / ????????2. The impact charphy value on V Groove with SMAW welding current of 110 A on ASTM A36 carbon steel is the best with the required impact charphy results (W) namely on V Groove of 73.519 J and the impact charphy value (K) on V Groove of 0.918 J / ????????2.

Effect of Metallurgical Fundamentals and Welding Processes on Joining of Dissimilar Steels

The dissimilar materials welding is characterized by several metallurgical characteristics which do not arise in similar materials welding. Service life of mixed joint strongly depends on manufacturing and operating conditions. In this study, welding of different materials will be investigated in a way that up-hill diffusion processes, hot cracking, dilution percentage, thermal characteristics of the material and welding procedure. Micro analyses of different material’s welding and metallurgical problems will be examined. The result of this study will allow us to explain potential joining mechanism for dissimilar steels.

Effect of Pin Length and Compression Force in Double Side Friction Stir Welding on Tensile Strength of AA1100

Friction Stir Welding (FSW) is solid state welding without additives and does not produce pollution. There are two FSW welding methods, namely single side (FSW) and double side (DFSW). The FSW process in previous studies using aluminum materials, especially AA 1100 type, has not obtained optimum joint strength. Therefore, it is necessary to conduct a research study on improving the quality of tensile strength of welding results using the DFSW method on AA1100. The purpose of this study is to determine the effect of variations in pin length and compressive force on the maximum tensile strength of the results of Double Side Friction Stir Welding Aluminum Alloy 1100 welding joints. The method used in this research is experimental. The welding process uses Double Side Friction Stir Welding, by varying two independent variables namely pin length 1.5 mm, 2 mm, 2.5 mm and compressive force 30 kg, 35 kg, 40 kg, 45 kg. The controlled variables used include travel speed (10 mm/min), heating temperature (250℃), shoulder diameter (25 mm), heating plate width (10 mm), and Aluminum AA1100 plate thickness (3.5 mm), with butt joint type welding. The data analysis used is Factorial Design of Experiment (DOE). The results of this study indicate that pin length and compressive force affect the tensile strength of AA1100 material welds. The maximum tensile strength value of DFSW welding results is 90.16 MPa or 80.5% of the tensile strength of the parent material. The maximum tensile strength value was obtained from the interaction of 2 mm pin length and 45 kg compressive force.

The influence of solid-state welding modes on the structure of the 12Cr18Ni10-Cu system joint

This study investigates the friction welding technology for joining the 12Х18Н10Т stainless steel and copper, focusing on optimizing welding parameters and analyzing the mechanical properties of the resulting joints. The research was conducted using experimental methods to determine the optimal parameters of friction welding. Mechanical tests, including tensile strength, hardness, and microstructure analysis, were performed to evaluate the quality of the welds. The results indicate that proper selection of friction welding parameters significantly affects the quality of the joint between the 12Х18Н10Т stainless steel and copper. Optimal welding conditions were identified, leading to strong mechanical properties and reliable joint performance. Microstructural analysis revealed uniform material distribution across the weld zone. This study contributes to the understanding of friction welding processes and the effects of different welding parameters on the microstructure and mechanical properties of dissimilar metal joints. The findings provide practical recommendations for the friction welding of dissimilar materials, emphasizing the importance of parameter control to prevent defect formation and optimize joint strength. This study offers valuable insights into the friction welding process of dissimilar materials, highlighting the role of specific parameters in controlling the formation of defects and improving mechanical properties. The findings are applicable to industries requiring durable joints between stainless steel and copper. The study focused on a limited range of welding speeds and pressures. Future research should explore a broader set of parameters to further refine the welding process and address issues related to internal oxidation and joint durability.

Investigation of Residual Stress Variation in Sequential Butt Welding and Pocket Material Removal Machining Processes Utilizing Pre-Stress Method: A 3D Simulation Approach

Investigation of Residual Stress Variation in Sequential Butt Welding and Pocket Material Removal Machining Processes Utilizing Pre-Stress Method: A 3D Simulation Approach

Heat Treatment Optimisation of Electron Beam Welded Reactor Pressure Vessel Steel

Electron beam welding (EBW) is a promising technology for the joining of large steel components such as pressure vessels. Notably, EBW does not use a filler metal, meaning that the weld and parent material (PM) should have the same composition. Accordingly, it may be possible to homogenise microstructure and properties across the weld given a suitable post-weld heat treatment (PWHT), essentially making the weld ‘disappear’. To investigate this possibility, three different PWHTs were applied to an SA508 Grade 4N weld. A stress-relief PWHT only had a relatively minor impact on the variations in microstructure and hardness across the fusion zone (FZ), heat-affected zone (HAZ) and PM versus the as-welded state, and compositional microsegregation in the FZ was unchanged. Hardness was successfully homogenised across the parent and weld in heat treatments involving a traditional 860 °C austenitisation, quench and temper, but compositional microsegregation persisted in the FZ. The addition of a homogenisation step at 1200 °C eliminated this microsegregation, with the weld area only remaining visible owing to the presence of compositional banding in the PM. However, homogenisation also led to the formation of undesirable prior austenite grain structures following subsequent re-austenitisation at 860 °C. Nevertheless, the application of PWHTs involving a full re-austenitisation seems promising for future applications.

Study on the Optimization of Process Parameters for Submerged Arc Welding of Hydrogen Production Reactor Material

In a hydrogen production reactor based on the principle of coal-to-hydrogen, the welds, which are considered the weak points, must exhibit a good impact resistance property and high hardness under special operating conditions. This paper investigates the influence of submerged arc welding (SAW) process parameters on the hardness and the impact resistance property of welds in the steel used for a hydrogen reactor. It establishes the relationship between the microstructure of the welds and their hardness and impact resistance property under varying welding parameters. Based on orthogonal welding experiments and a comprehensive balance method, the welding parameters were optimized to obtain the best combination of parameters. The results indicate that as the current and voltage increase, the average hardness of the welds first decreases and then increases, while the impact resistance property initially improves before declining. As the welding speed increases, the average hardness of the welds initially increases and then decreases, while the impact resistance property gradually declines. After optimization under specific experimental conditions, the best welding parameters are determined to be a current (I) of 320 A, a voltage (U) of 34 V, and a welding speed (v) of 33 cm/min. Compared to the base metal, the hardness of the weld increased by 36.1%, and the impact resistance property improved by 71.5%.

Strengthening and embrittlement mechanisms in laser-welded additively manufactured Inconel 718 superalloy

Although laser-welded additively manufactured Inconel 718 joints find numerous high-temperature industrial applications, their strengthening and embrittlement mechanisms remain underexplored. To bridge this gap, we herein prepared such joints by the laser welding of the as-built material (built-LW), laser welding of double-aging heat-treated as-built material (DAT-LW), and double-aging heat treatment of laser-welded as-built material (LW-DAT). The microstructures of the joint fusion zones (FZs) were examined using scanning electron microscopy (electron backscatter diffraction and secondary electron imaging), while nanoscale features were probed by transmission electron microscopy, and mechanical properties were evaluated using microindentation hardness (HIT) measurements and tensile tests. The FZs of the built-LW and DAT-LW joints contained no strengthening precipitates, such as the Laves phase and γ′ and γ″ nanoparticles. In stark contrast, the FZ of the LW-DAT joint contained spherical nanoparticles of the γ′ and γ″ phases responsible for precipitation hardening. The DAT-LW joint displayed base metal (BM) strengthening and FZ softening (HIT = 6.47 and 3.6 GPa, respectively), whereas the LW-DAT joint demonstrated BM and FZ strengthening (HIT = 6.2 and 6.5 GPa, respectively). The built-LW joint exhibited the lowest ultimate tensile strength (UTS) of 833 MPa, primarily because of the absence of strengthening precipitates. The DAT-LW joint, despite experiencing FZ softening, exhibited a higher UTS of 1086 MPa and a limited elongation of 2%, while the LW-DAT joint featured the highest UTS of 1440 MPa, primarily because of the enhancement of nanosized γ′ and γ″ strengthening phases facilitated by postwelding double-aging heat treatment.

Advancements in Laser Beam Welding for Dissimilar Material Joining: Exploring Weldability Assessment, Challenges, Parametric Influences on the Mechanical–Microstructural Properties in Steel‐Alloyed Metal Combinations

With the growing demands in several sectors such as the automotive, biomedical, construction, shipbuilding, aerospace, and other manufacturing units, employment of welding techniques has observed a rapid boom in recent times. Laser welding technique is one such recent sign of progress in the fabrication field. Laser beam welding is a radiant energy welding process widely adapted to join a variety of metals and nonmetals. The demand for the dissimilar material welding increases with the increase in industrial needs. Several severe challenges need to be overcome to have such dissimilar welded components mainly as the significant difference in melting point, different combinations of mechanical, metallurgical, chemical, and thermal properties. The present approach attempts to study the weldability of steel and its alloys with other metals and parametric effects on mechanical and microstructural properties. The study reveals that the laser beam offset plays a vital role to achieve sound quality welded joint with desirable weld strength. It has been found that 0.32 mm beam offset generates 243 MPa ultimate tensile strength in the 316L to TC4 dissimilar welds. Again, the addition of interlayers also improves the joint strength of both steel‐to‐aluminum and steel‐to‐titanium dissimilar welded joints.

Development of Costing Model for Butt Joint Process using Mild Steel with Robotic GMAW: A Malaysian Context

This paper is about the development of a costing model aimed at determining the pricing strategy for a component manufactured through the welding process. Cost estimation in welding processes is crucial for industries due to various influencing factors like welding time, length, and joint type. Calculating welding costs involves considering various methods and factors. One method compares theoretical filling metal amounts with on-site welding material consumption, factoring in the welding difficulty coefficient. Additionally, Time Driven Activity Based Costing (TDABC) is one of the costing methods used to analyze input data and estimate welding costs accurately and efficiently, specifically in the GMAW process. Moreover, a comprehensive costing model developed by ESAB incorporates variables such as labor costs, electrode expenses, shielding gas usage, and overall power costs. In this paper, the selected welding design configuration is a double Vgroove butt joint using mild steel, ER70S-3 as filler wire, and S235 mild steel as substrate. Based on the chosen design, the welding cost model will be developed to analyze the cost of the butt joint welding process based on timedriven activity-based costing (TDABC) method. The outcome of this study is the total cost to manufacture the Double V-Groove butt joint project in terms of materials, labor, and equipment. Furthermore, subsequent efforts will be directed toward systematically enhancing the welding cost model to include a broader spectrum of materials, various part dimensions, and differing deposition rates.

Investigation of Electromagnetic Wave Propagation in Photonic-like Welded Materials Using the Finite Element Method.

In this study, two identical and two dissimilar materials are conjoined by applying the friction welding method to yield various rods. This investigation's primary focus entails examining the repercussions associated with the heat-affected zone (HAZ) arising from elevated temperatures at the welding interfaces on the propagation of electromagnetic (EM) waves within the resultant structures. The study incorporates the photonic crystal approach in conjunction with Maxwell's equations, and the subsequent solution of the latter is executed using the finite element method. The subdivision of the structures into fifteen elements is predicated upon the assumption of the electromagnetic wave number of the m-th segment, km, of discrete segments. The finite element method is then administered to the HAZ regions of the structures, wherein the HAZ is discretised into one, three, and five elements, respectively.

Study on Welding Characteristics and Parameters of Gas Metal Arc Welding for A516 Grade 70 Steel with ER70S-6 and ER308LSi Filler Materials.

Welding is a crucial process in joining metals, especially in the fabrication industry. Thisresearch aimed to investigate the effects of using two different filler materials, ER70S-6 and ER308LSi, with nine combinations of wire feeder speed (WFS) and shielding gas flow rate (GFR), on weld joints. The study focused on the weld quality and material properties of Gas Metal Arc Welded (GMAW) butt joints of ASTM A516 G70 plates, characterized through visual inspection, liquid penetrant testing, tensile testing, hardness testing, and optical microscopy. Results indicated that the highest ultimate tensile strength and hardness were achieved at 4 m/min WFS and 15 L/min GFR with ER70S-6, and 5 m/min WFS and 20 L/min GFR with ER308LSi. The specimens welded with ER308LSi demonstrated superior mechanical properties compared to those welded with ER70S-6. Additionally, the study revealed the influence of microstructural changes from the base metal (BM) to the heat-affected zone (HAZ) and fusion zone (FZ), with finer and more compact grain structures contributing to higher hardness values. These findings underscore the importance of selecting appropriate filler materials, WFS, and GFR to achieve the desired weld quality and material properties for A516 G70 low-carbon steel welded joints.

Effect of welding layers and interlayer temperature on welding residual stress and deformation of Q345/316L dissimilar steel

Abstract Dissimilar steel welding is widely used in machinery, chemical industry, electric power and other fields. Due to the different welding materials, the distribution of residual stress and deformation of welded joints is complex. In order to study the influencing factors and variation rules of residual stress and deformation distribution of dissimilar steel joints, considering the nonlinear physical and mechanical properties of welding materials and the latent heat of phase change during welding, based on the SYSWELD platform, taking Q345 carbon steel and 316L stainless steel as the research objects, the double ellipsoid heat source model was used to study the effects of welding layers and interlayer temperature on the residual stress and deformation of joints. The results show that the increase of the number of welding layers is beneficial to expand the distribution of residual stress, and has no obvious effect on the residual stress of the weld, but it will reduce the residual stress of the base metal near the weld. However, the increase of the number of layers will also aggravate the deformation of the weld. Therefore, it is necessary to consider the design of the number of welding layers considering the thickness of the component. At the same time, the study also found that the interlayer temperature has a certain influence on the residual stress and deformation of the joint. The increase of the interlayer temperature will reduce the welding angle deformation, and has little effect on the transverse shrinkage and the residual stress of the joint. Therefore, a lower interlayer temperature should be selected for multi-layer and multi-pass welding of dissimilar steel to ensure the quality of the welded joint.

Characteristics of Solidification Cracking for Ni-P Coated Cu-Al5052 Single-Mode Fiber Laser Welds

This study fundamentally examines the characteristics of solidification cracking in Cu-Al5052 single-mode fiber laser welding by utilizing uncoated and Ni-P coated Cu plates for the high durability busbar welding of pouch-type lithium-ion battery packs. Weld solidification cracking was confirmed regardless of Ni-P coating for both weld materials. However, there were differences in the regions of crack occurrence. Unlike the uncoated Cu-Al5052 welds where cracks occurred randomly within the fusion zone, for the Ni-P coated Cu-Al5052 welds, solidification cracks were concentrated near the faying surface of the upper and lower materials, particularly near the fusion line. The effect of the Ni and P components on the solidification cracking susceptibility, i.e., the welding solidification temperature range, was considered. Diffusion-controlled Scheil’s solidification calculations revealed that the mushy zone range enlarged with the use of a Ni coating layer. It was confirmed that an extremely wide mushy zone range of 1060 K was calculated at the solidification cracking region. Furthermore, P was also identified as an element that expands the solidification temperature range based on the Cu-P binary system. Consequently, during the laser welding of Cu-Al5052 dissimilar materials, the behavior of solidification cracking in the welds is influenced by the composition of the coating material and the incorporated composition within the weld fusion zone. Hence, it is necessary to select the optimal coating material and layer thickness considering weld solidification cracking susceptibility.