The concept of brittle crack arrest has recently become an internationally focused issue for container ships. The International Association of Classification Society (IACS) also prescribed the unified requirement (UR) for brittle crack arrest design, and brittle crack arrest design has been internationally authorized. As one of the methods to evaluate brittle crack arrestability, the crack arrest temperature

In this study, A7204-T4 aluminum alloy sheet with a thickness of 6 mm was welded using fiber laser variable polarity tungsten inert gas (VPTIG) hybrid welding with ER5356 filler wire, during which Nb (niobium) foils with different thicknesses (10 μm, 25 μm, 35 μm, and 50 μm) were preset between the butt joint faces. The joint microstructure and properties with different Nb content were investigated

Currently used approaches for the modeling of the heat input in gas metal arc (GMA) welding process simulation usually assume an axisymmetrical Gaussian distribution of heat flux in the cathode region. However, as in GMA welding, cathodic electron emission of non-refractory metals is involved; the attachment region consists of multiple highly mobile cathode spots, which have a highly concentrated current

Refill friction stir spot welding (RFSSW) is a highly flexible and promising solid-state joining method for aluminium alloys. Alternatively, resistance spot welding (RSW) can be stated as an appropriate joining method which can be automated and used within a high-volume production due to short process times. Both processes do not need any additional elements and a flat surface on both sides of the

The ultrasonic joining process was recently introduced as an alternative concept to join through-the-thickness reinforced metal-composite hybrid structures. In this work, the investigation of joining process parameters effect on the joint mechanical performance of Ti-6Al-4V-glass-fiber-reinforced polyetherimide overlap joints was carried out by Box-Behnken design of experiments. The individual and

Wire and arc additive manufacturing (WAAM) technology is growing in interest in the last years. The technology enables the manufacturing of real geometries by overlapping weld beads and is well suited for metallic parts with high buy-to-fly ratio. Manufacturing costs and time are critical issues which determine the business case. Therefore, it is necessary to develop strategies that minimise the production

In the past, most approaches to reduce welding fume emissions were primarily based on welding consumables, whereas in the context of the present work, a new concept with direct reference to the welding process technology is pursued. Many other measures to improve occupational health and safety, such as use of extended personal protective equipment (e.g., forced air ventilated helmets) and extraction

Additive manufactured (AM) lattice structures have become very prominent in recent times especially in air and spacecraft industry for their lower weight and specific mechanical properties. Their stiffness and strength can be controlled by their geometrical properties, such as the shape and dimensions of the unit cell. Geometrical and dimensional accuracy of the AM lattices is therefore one of the

This paper presents the influence of welding current, electrode-workpiece distance, electrode composition, electrode diameter, electrode tip angle, shielding gas composition, and pulsed current frequency over the arc stagnation pressure of gas tungsten arc welding (GTAW). In this study, arc application tests were carried out over a 1-mm diameter hole on a non-melting water-cooled copper plate. The

This study investigated the applicability of low transformation temperature (LTT) arc welding consumables to improve fatigue strength against weld root failure. Transverse attachment joints formed by single-sided welding, similar to rib-to-deck connections in orthotropic steel bridge decks, were fabricated using an LTT welding consumable and conventional welding consumable. Fatigue tests were performed

The aluminothermic welding (ATW) process is the most commonly used welding process for welding rails (track) in the field. The large amount of weld metal added in the ATW process may result in a wide uneven surface zone on the rail head, which may, in rare cases, lead to irregularities in wear and plastic deformation due to high dynamic wheel-rail forces as wheels pass. The present paper studies the

The publication of this article unfortunately contained a mistake. Table 8 of Appendix B was not correct; please see the updated table below.

In 2016, the International Institute of Welding (IIW) published a recommendation for high-frequency mechanical impact (HFMI) treatment for improving the fatigue strength of welded joints. Since the publication of the HFMI recommendations, numerous of studies have been published with a considerable amount of new fatigue test data focusing on various aspects of the improvement; influence of base material

Unlike other joining techniques, laser transmission welding offers unique advantages such as selective and contactless energy deposition. This enables the fabrication of flexible seam geometries at low mechanical and thermal stresses. However, the use of absorbing additives for the lower joining partner such as carbon black is crucial as most polymers are transparent in the spectral range of typical

In this paper, T-joint samples in a 1300 MPa yield strength steel were produced using conventional or low transformation temperature (LTT) type consumables. The welded samples were either subjected to high-frequency mechanical impact (HFMI) treatment or to shot-peening. Fatigue testing was performed under fully reversed, constant amplitude bending load. Shot-peening gave a significant increase in fatigue

A model was established for four-element material with HCP structure by EET. The filler of TiZrCuNi was analyzed by the model. It was found that Ni element is beneficial for the strength of the filler but Cu element is beneficial for the ductility of the filler. It showed that controlling the amount of Cu and Ni with the proper distribution of them was important. Compared with the filler Ti-13Zr-22Cu-9Ni

The purpose of this study was to evaluate the microstructural evolution of softened zones after cyclic plastic deformation (CPD) and the effect of CPD on the mechanical properties of X60 reeled-pipeline welded joints. The results showed that the existence of softened zone caused the deformation to be mainly concentrated in this area during CPD process. The minimum hardness of softened zone was 18 HV

This paper deals with the stress analysis of a cantilever box beam subjected to static or fluctuating torsional moment loading. Such beams may have multiple critical locations from the strength point of view; one interesting detail is the cross section where the loading is imposed. However, such details can be typically designed to possess smooth shapes, resulting in moderate stress concentrations

This paper proposes an estimation method for crack tip opening displacement (CTOD) in laser welds. The theoretical model for CTOD estimation developed by Dugdale and Bilby et al. (DBCS model) was used for laser-welded plates. The yield stress of the laser weld metal and narrow hard zone width affected the CTOD, and the correction of yield stress by using the DBCS model to obtain a suitable CTOD estimation

The objectives of this study are: (1) to verify whether using linear heat input alone is sufficient to predict the resulting microstructure of Ti6Al4V and (2) to demonstrate the potential of single-step process of functionally graded material using powder bed fusion. In laser powder bed fusion, linear heat input is defined as the ratio of laser power to scan speed. It is a key process variable that

The present investigations on generative manufacturing using metallic materials pursue the idea of transferring the microscopic structural morphology of a dual-phase steel in modified form to the macroscopic level. The aim is to be able to join materials of different lattice modifications and to combine their positive properties. This applies in particular to the combination of high tensile strength

A heat treatment technique was applied on standard duplex stainless steel welds in order to investigate the influence of thermal treatments, e.g., multi-pass welding, on the microstructure. By using a stationary arc, a spatial steady-state temperature field ranging from liquidus to room temperature evolves within a single sample and results in a graded microstructure. The arc heat treatment was applied

The induction of near-surface compressive residual stress is an important factor for fatigue life improvement of HFMI-treated welded joints. However, the relaxation of these beneficial residual stresses under single overload peaks under variable amplitude and service loads may significantly reduce fatigue life improvement. For this reason, several recommendations exist to limit the maximum applied

Composite structures have wide applications in mechanical fields. Such structures consist of several joints, which may run a risk of eventually weakening a structure in case of excessive weight. It is, therefore, necessary to strengthen a structure so as to reduce the chance of failure. The present study was undertaken with a model of tubular T-joint having adhesive fillet. It also focussed on three-dimensional

High-strength steel heavy plates are usually covered with a mill scale after production. Morphology, structure, and chemical composition are determined by several factors, e.g., rolling parameters, cooling rate, quenching method, and alloying elements. As the mill scale might cause pore formation and process instability, it is preferably removed prior to welding. In welding practice, the removal of

High-strength low-alloy or microalloyed steels are thermo-mechanically control processed (TMCP) to achieve desired microstructures and mechanical properties, and microalloy additions are critical for obtaining optimum properties. The steel of interest in this study is microalloyed with approximately 0.1 wt% Nb, levels that are typical in pipeline steels such as X70. Submerged arc welding (SAW) is a

The fracture mechanics-based IBESS approach is applied to the determination of FAT classes of butt welds with crack initiation along the weld toe. The aim is an investigation of the effect of the geometrical parameters toe radius, flank angle, reinforcement and secondary notches such as roughness or undercuts. The influence of these parameters is discussed both individually and in combination; however

The simulative accelerated creep test (ACT) was developed as a response to an overall need of gaining in a short time useful physical data for determining long-term behaviour of materials exposed to operation under stress at elevated temperatures in power generation and chemical processing industries. Additionally, the recently frequent power plant shut-downs due to adding solar/wind power to the net

Due to high hot crack susceptibility of Al-Mg-Si alloys, autogenous welding by rectangular pulsed laser beam has not been generally successful in the removal of cracks. In this research, the effect of pulsed Nd:YAG laser parameters and preheating on the creation of hot cracks in the 6061-T6 aluminum alloy was investigated. The sample that was fabricated by the laser parameters including 1 Hz, 0.12 mm/s

Shielding gas nozzle diameter variation and its impact on the anodic power distribution of low-current tungsten inert gas arcs were investigated, while maintaining either shielding gas flow rate or flow velocity constant. In addition, the effects of anode surface condition and flow behaviour type (laminar or turbulent) caused by the shielding gas nozzle applied were studied. It was found that arcs

The subject of this study is how, and to what extent, Varestraint/Transvarestraint test results are influenced by both testing parameters and characteristics of evaluation methods. Several different high-alloyed martensitic LTT (low transformation temperature) filler materials, CrNi and CrMn type, were selected for examination due to their rather distinctive solidification cracking behaviour, which

One of the methods to achieve local change in material properties when producing high strength parts with tailored mechanical properties is variating temperature histories in the furnace prior to hot stamping. This causes changes in surface layer development of coated steels and thus differences in contact resistances, which determine heat development during the resistance welding process. To get a

Arc welding of aluminium and steel joins are commonly inundated by the formation of brittle intermetallic compounds (IMC) at the aluminium-steel interface. As the formation of IMC is closely related to the heat input into the base metals, it is hypothesised that the ability to regulate the heat input would enable the control of the thickness of IMC. This paper proposes the use of a pulse plasma MIGW

Welding of 13CrMoV9-10 vanadium steel requires care due to an increased susceptibility to stress relief cracking during post weld heat treatment. Previous research into the crack formation in creep-resistant steels has focused on thermal and metallurgical factors; however, little knowledge has been gathered regarding the crack formation during post weld heat treatment considering real-life restraint

The pin tool used in conventional friction stir spot welding creates a keyhole that reduces the surface quality of the welds and has a negative effect on the corrosion resistance and mechanical properties. In the present work, protrusion friction stir spot welding, a simple method that avoids keyhole formation, is applied to weld AA6061 thin sheets with thickness of 1 mm. Tool rotation speed is constant

Varestraint testing is commonly used to evaluate hot cracking susceptibility of materials. In this paper, the dependence of operators and evaluation technique on test results is studied for a high-temperature austenitic stainless steel (UNS S31035). Samples were tested at six different strain levels ranging from 0.7 to 3.8%. Four different operators evaluated the same samples following the same instructions

The avoidance of failures during the fabrication or operation of petrochemical reactors made of creep-resistant, low-alloy steels as 13CrMoV9-10 requires still research despite over 60 years of international investigations in the field of stress relief cracking. The quality of modern base materials and filler metals leads to the fact that previously known crack causes, such as impurities of S or P

A magnetic generating device was proposed to regulate the transverse and backward flow of weld pool for high-speed gas metal arc welding (GMAW). Compound external magnetic field (EMF) was simulated to verify the feasibility of designed magnetic generating device. The highest welding speed with good weld bead appearance was 1.7 m/min with the wire feed speed of 9.0 m/min when compound EMF was applied

Currently used approaches for modeling the cathodic heat input in gas metal arc welding (GMAW) process simulation are usually based on very simplified approaches, either using a Rykalin-Rosenthal-distributed heat flux or a thermal conductivity approach, which do not reflect the deep physical processes involved. In this paper, a new approach for the calculation of the arc-cathode coupling in GMAW is

This study focuses on the influence of the welding parameters on defectiveness, thermal field and grain size in friction stir welding of aluminium alloy 7075-T6. Different welded specimens were produced employing various rotational speeds and welding speeds. In the first part of the analysis, the quality of the joints was evaluated by microscopic observation of the jointed cross-sections to investigate

Gas metal arc welding (GMAW) processes are used in a wide range of applications due to their high productivity and flexibility. Nevertheless, the supplied melting wire electrode leads to a coupling of material and heat input. Therefore, an increase of the melting rate correlates with an increase of the heat input by the arc at the same time. A possibility to separate material and heat input is to use

Post weld heat treatment is the most widely used technique to restore the strength of aluminum welds by recrystallization of precipitates and often requires cumbersome, energy intensive, and time-consuming heat treatments. Equal channel angular pressing (ECAP) is proposed for the first time as an alternative to the heat treatment of welded AA6061 samples, welded by the gas tungsten arc welding process

This paper presents the results of investigations on wetting with Pd-Ni-Cr(Me)-Ge system brazing filler metal of pure nickel, high-temperature alloy based on nickel aluminide (Ni3Al). Micro-X-ray spectrum examinations showed that spread of Pd-Ni-Cr(Ме)-Ge system brazing filler metal over pure nickel substrate, which has no aluminum, promoted crystallization of brazing filler metal in the form of a

The Selective Laser Melting process involves multiple factors that are detrimental to fatigue life. It is crucial to select optimal processing parameters to avoid internal porosity, source of early failure through crack initiation mechanisms. Surface condition, especially high roughness values, may also be a critical factor for crack initiation. Influence of surface condition must be studied in the

The susceptibility to solidification cracking of unstabilized and stabilized ferritic stainless steels was investigated using self-restrained Houldcroft and Modified Varestraint-Transvarestraint (MVT) tests. Nine steel grades of unstabilized and stabilized ferritic stainless steels were used in this study. Seven steels comprising an unstabilized, two monostabilized (Ti and Nb) respectively, three dual

Control of the melt pool size is necessary to achieve more homogenous material properties in wire arc additive manufacturing (WAAM). The melt pool size can be measured by camera imaging or temperature field measurement. The paper aims to investigate the feasibility of using a high dynamic range two-colored pyrometric camera (Pyrocam) for melt pool size measurement in a gas metal arc welding–based WAAM

Due to the importance of the weld metal corrosion, this study aims at the effect of using Ni in weld metals on their corrosion parameters and microstructures. In this regard, the effect of negligible amounts of Ni up to 8.0 wt.% is examined on weld metals made of weld electrodes of the E8018-G type in conditions equal to industrial standards. The corrosion parameters of the weld metals are evaluated

This study approaches conflicting aspects of high-performance MIG/MAG associated with penetration. It demonstrates that a simpler version with voltage control enables the obtainment of good results as long as some premises, related to the power source, are maintained. The molten pool in this case is a cavity in the piece, which is caused by a condition referred to as “buried arc.” In this technique

An experimental and numerical research program is executed to investigate the fatigue lifetime increase due to grinding-type post-weld treatment method. Plate edge gusset, longitudinal attachment and T-type joint specimens are investigated using fatigue test results, numerical models and mathematical statistical tools. The favourable impact of grinding on fatigue lifetime of the analysed joints is

In the present work, DH36 steel and AISI 1008 steel sheets were joined using friction stir welding (FSW) process to investigate the influence of the rotational speed, traverse speed, and tool offset on temperature distribution, z-force, microstructure, and mechanical properties of the welded specimens. At a traverse speed (v) of 50 mm/min with a rotational speed (ω) of 600 rpm and tool offset of 2 mm

Abstract Cu/Al composite structures have considerable prospect for applications in refrigeration, automotive, power plant, and aerospace industries. The corrosion resistance of the Cu/Al joints is crucial to these applications. In this paper, corrosion behaviors of the Cu/Al joints brazed with three kinds of commercial Zn-Al filler metals were evaluated by salt spray test. The microstructure and composition

The effects of surface roughness were studied on microstructural and mechanical properties of solid-state diffusion bonding between two dissimilar alloys of magnesium AZ91-D and aluminum 6061 by means of hot pressing. Although applied pressure, temperature, and duration of diffusion bonding are known as the most effective parameters, surface roughness can alter the mechanical and microstructural properties

Friction stir welding (FSW) is a solid-state welding technology which is frequently used for welding of thermoplastic and metallic alloys in the automobile and aerospace industries. Polylactic acid (PLA) is a biodegradable thermoplastic polymer. PLA can replace petroleum-based polymer in many applications if the FSW process can be used for welding of PLA-based engineering components. In the present

Glass products with precise and sophisticated shapes are highly demanded in the field of MEMS due to their excellent properties. Ultrashort pulsed laser has been expected to be a powerful and reliable tool for micro-welding of glass. Focusing condition such as numerical aperture (N.A.) is a critical parameter that controls how ultrashort laser pulses interact with and propagate in glass, and it has