EUROPEAN CONGRESS AND EXHIBITION ON ADVANCED MATERIALS AND PROCESSES - EUROMAT 2021

Wire-based additive manufacturing (WAM) has been shown to be a feasible technology for manufacturing of metallic components of medium complexity with a high deposition rate. Thereby, wire feedstock is conveyed into an energy source such as an electric or plasma arc, in turn melting the wire and forming a droplet, which is subsequently deposited on the substrate or the previous layers. For an...

Ultra high strength steel (UHSS) significantly contribute to lightweight design. However, it is essential that the excellent mechanical properties are maintained after the applied welding process in terms of structural safety such as strength and ductility. This study investigates the microstructural and mechanical properties of MAG welded X-joints of 20mm thick S1100 thermomechanically rolled...

The present paper examines the fatigue performance of eleven (11) 90-degree welded X-joint scaled-down specimens, commonly used in offshore tubular steel structures. The braces and the chord are 8-inch-diameter tubes made of S355J2 steel, with a brace-to-chord-thickness ratio of 0.6. The research work is part of an extensive research program, with acronym JABACO (2015-2018), sponsored by the...

The energy production of the future will be dominated by CO2-emission free techniques like wind turbines and become essential in scope of the planned hydrogen economy. As onshore installation capacity is limited, the increase of the number of offshore wind turbines (OWT) is a major goal. In that connection, the OWTs continously increase in size and weight and demand adequate foundations...

Joining materials together is an integral part of the chemical, energy, and automotive industries. Fusion welding with Tungsten inert gas (TIG) process normally uses a non-expendable electrode to weld materials and is widely adopted in modern design due to its stability and versatility. The molten metal flow in the weld pool has an immediate impact on the performance of the welded part by...

The joining of titanium alloys to advanced ceramics allows the possibility of combining their excellent properties, which is essential to expand the range of potential applications of this last one, e.g., aerospace industry and microelectromechanical systems [1]. However, the joining of these dissimilar materials has several challenges due to their distinct physical and mechanical properties....

Type 316LN austenitic stainless-steel is a major structural material used in various components of fast breeder reactors. A suitable single pass welding process must be considered that gives better weldability in the fabrication of thick components. In this regard, the activated TIG welding process can weld thick sections by a single pass up to 12 mm. An ideal weldment should be free from...

Intermetallic phases forming at the interface between aluminum and steel during thermal joining strongly affect the reliability of multi-material components. Controlling the thickness of the intermetallic layer is crucial for achieving reliable aluminum-steel joints, as thick layers may significantly impair the mechanical properties of dissimilar joints. The thickness is influenced by the...

3rd generation advanced high strength steels present a good compromise between strength, ductility and in-service properties in the automotive industry, which allow structural parts to be made from thinner sheets compared to other alternative materials. However, when zinc coated, they are prone to suffer from Liquid Metal Embrittlement (LME) during Resistance Spot Welding process (RSW), as a...

In the paper the effect of welding technology on the microstructure and mechanical properties of butt welded joints was presented. Metallographic examinations based on light microscopy and SEM were conducted on butt welded joints of 316Ti stainless steel. For each of the weldments, detailed analysis was conducted on the phase composition, microstructure characteristics and mechanical...

Among different joining methods the electron beam welding is recently applied for manufacturing of turbine components from temperature-resistant nickel-based conventionally cast Alloy 247.
However, the high susceptibility to hot cracking and especially to solidification cracking is a serious obstacle.
Experiments indicate a significant reducing of hot cracking when welding outside the...

Advanced High Strength Steels have been developed within the last decades to meet the growing demands for weight reduction and improved crashworthiness properties in the automotive industry. They present an effective combination of formability and weldability, which is of interest for the production of three-dimensional automotive body parts by laser welding. The aim of this work is to...

Laser transmission welding is a widely used process for joining thermoplastics. Of the two materials involved in the welding process, one should be transparent/semi-transparent to laser wavelength, and the other absorbent to the same wavelength. A laser beam is transmitted through the transparent material and is absorbed at the interface of the two materials.
During laser welding of...

Friction stir processing (FSP) was applied on pure Cu to obtain a stir zone with very fine grain size with the aid of severe plastic deformation. Yet using FSP, it is impossible to obtain a uniform cross-section as far as the microstructure and mechanical properties are concerned. To reduce the effect of this limitation, in the current study, the material was processed on both sides, thus...

High entropy alloys (HEA) are a new class of materials. In contrast to conventional alloys, HEA are single-phase alloys with at least five alloying elements. HEA have enormous application potential due to (postulated) excellent structural property combinations from low to high temperatures. For HEA-application as structural materials in real components, a key issue is the suitability for...

The aim of this work is the study of the weldability of high strength steel used as tendons for strand anchors with the friction welding process. The motivation of this study is to provide extensions for strand anchors which are widely used (e.g. slope stabilization, retaining structures, bridge abutments) in civil engineering. These extensions are necessary to extend the lifespan of such...

Materials with ultrafine grained (UFG) structure exhibit significant improvement in mechanical properties due to reduced grain size below 1 µm. To obtain such materials in a bulk form severe plastic deformation processes are used. Nevertheless, high stored energy and highly deformed structure result in reduced thermal stability, which causes a rapid grain growth at elevated temperature. This...

Multi material components, also known as hybrid material systems, are of growing interest to industry. The ongoing need for high performance structural and functional components requires that combinations of dissimilar materials are explored in order to develop and efficiently produce products that achieve a balance of appropriate characteristics or new properties at reasonable cost. Besides...

Friction Stir Welding (FSW) is an innovative solid-state process well-known for the excellent microstructural and mechanical properties of the resulting permanent joints. Nowdays, dissimilar joints in aluminium alloys are widely employed for structural applications. Moreover, the addition of reinforcement particles in the joint line during the FSW process is even more a topical issue to...

The aim of this work is to study the brazing of zirconia to titanium with pure gold. Brazing experiments were carried out under high vacuum (10-4 Pa) at different temperatures.
In order to determine the mechanisms of interfacial interactions at ZrO2/Au interface, wetting of zirconia by AuTi alloys was also studied. The spreading kinetics of the wetting process has been determined by sessile...

Brazing and active metal brazing are reported to be straightforward techniques to produce sound metal/ceramic joints. The performance of brazed joints is highly dependent on the microstructure developed at the interface. For instance, the use of Ag-Cu eutectic based fillers strongly limits the operating temperature of joints due the extensive formation of (Ag) at the central zones of the...

In this study, interfacial morphology, microstructure and mechanical property of joints produced by explosive welding between Mg alloys AZ31, AZ61 and AZ80 and Al alloy A6N01 were investigated. In all joined plates, the bonding interface has a periodic wavy shape. In the Al matrix side, deformed grains were observed near the bonding interface, while recrystallized grains were observed in the...

Continuous induction welding is particularly suitable for joining carbon fiber-reinforced polymer composites (CFRPC) with thermoplastic matrix, as the energy required for welding is introduced without contact and leads to intrinsic volumetric heating of the adherends. However, the heating is not homogeneous in thickness direction of the laminate. Instead, it leads to a temperature maximum on...

Aerospace industries have high interest in masts, structural reinforcement of platforms, deployable structures and similar solutions that combine dimensional accuracy with robustness, foldability and lightness. Components that integrate aluminium and carbon fibre reinforced plastics (CFRP) are nice candidates due to their mechanical properties and low density. The use of versatile joints with...

Since the first appearance of shape memory alloys in the early 60s, the interest in shape memory applications has been constantly increasing.Shape memory alloys based on Nickel and Titanium provide the best combination of material properties for many commercial applications in the medical and industrial field. One of the first successful applications of NiTi alloys have been clamping sleeves...

Self-piercing riveting (SPR) combined with adhesive bonding has been established as efficient hybrid joining technology for manufacturing lightweight car bodies. In order to exploit the advantages offered by multi-material design, this work investigates the feasibility of joining aluminum alloys with high-strength steels (HSS), however, against the favorable joining direction. Four hybrid...