Fatigue analysis and design of arc-welded and laser-welded lap joints: Toe vs. root induced failure

Fatigue might be the governing limit state in marine structures mainly induced by the waves and wind. Therefore, using a lap joint for the shell plating to replicate the appearance of a riveted joint for a retro yacht is critical due to the limited fatigue resistance. For this joint type cracks initiated at the root, which should always be...

Laser butt welding of thin stainless steel 316L sheets in asymmetric configurations: A numerical study

Laser butt welding of thin metal sheets is a widely used fusion-based joining technique in industrial manufacturing. A comprehensive understanding of the complex transport phenomena during the welding process is essential for achieving high-quality welds. In the present work, high-fidelity numerical simulations are employed to investigate the...

Microstructure Study of Pulsed Laser Beam Welded Oxide Dispersion-Strengthened (ODS) Eurofer Steel

Oxide dispersion-strengthened (ODS) Eurofer steel was laser welded using a short pulse duration and a designed pattern to minimise local heat accumulation. With a laser power of 2500 W and a duration of more than 3 ms, a full penetration can be obtained in a 1 mm thick plate. Material loss was observed in the fusion zone due to metal...

Applicability study of pulsed laser beam welding on ferritic–martensitic ODS eurofer steel

Pulsed laser beam welding was used successfully to join the oxide dispersion-strengthened (ODS) Eurofer steel. The joining was conducted with a laser power of 2500 W and a pulsed duration of 4 ms. With the filler material being used, a minor material loss and microvoids were observed in the joint. The microstructure of the fusion zone...

Study of solidification cracking during laser welding in advanced high strength steels: A combined experimental and numerical approach

Preventing solidification cracking is an essential prerequisite for the safety of a welded structure. An undetected solidification crack has the potential to cause premature failure during service. Two conditions generated by a weld thermal cycle are responsible for the initiation of solidification cracks. The first is the presence of excessive...

Evaluation of solidification cracking susceptibility during laser welding in advanced high strength automotive steels

Solidification cracking susceptibility during laser welding was studied experimentally and numerically in advanced high strength steel sheets, namely transformation-induced plasticity (TRIP) and dual phase (DP) steel. Using the same heat input, laser bead-on-plate welding was carried out on single sided clamped specimens at various starting...

Residual stress measurements and model validation of single and double pulse resistance spot welded advanced high strength steel

Advanced high strength steels (AHSS) are increasingly used in automotive industry; thousands of resistance spot welds are applied to car body-in-white. High alloying levels of AHSS result in lower weldability. Residual stresses play an essential role on the formation of defects and the mechanical performance of the weld. An electrical-thermal...

Study of solidification cracking in advanced high strength automotive steels

Advanced high-strength steels (AHSS), which are increasingly used in the automotive industry, meet many functional requirements such as high strength and crash resistance. Some of these steels contain high amounts of alloying elements, which are required to achieve the necessary mechanical properties, but render these steels susceptible to weld...

In situ strain investigation during laser welding using digital image correlation and finite-element-based numerical simulation

In situ strain evolution during laser welding has been measured by means of digital image correlation to assess the susceptibility of an advanced high strength automotive steel to solidification cracking. A novel method realised using auxiliary illumination and optical narrow bandpass filter allowed strain measurements as close as 1.5 mm from...

Investigation on hot cracking during laser welding by means of experimental and numerical methods

Hot cracking during laser welding of Transformation Induce Plasticity (TRIP) steel at the edges of steel flanges can be a problem. In this study, modified hot cracking tests were performed by welding on a single-side clamped specimen at various distances from the free edge, while the heat input and external constraints remained constant. In situ...

Study of solidification cracking susceptibility during laser welding in an advanced high strength automotive steel

Susceptibility to weld solidification cracking in transformation-induced plasticity steel sheets was studied using a modified standard hot cracking test used in the automotive industry. To vary the amount of self-restraint, bead-on-plate laser welding was carried out on a single-sided clamped specimen at increasing distances from the free...

Hot cracking investigation during laser welding of high-strength steels with multi-scale modelling approach

Hot cracking during laser welding of advanced high-strength steels is reported to be a serious problem by automotive manufacturers. In this work, hot cracking susceptibilities of transformation-induced plasticity (TRIP) and dual-phase (DP) steels are studied based on a multi-scale modelling approach. Transient temperatures measured from...

Laser Welding of Zinc Coated Steel Without a Pre-set gap

The major problem during laser welding of zinc coated sheet steel in an overlap configuration is the zinc vapour produced at the interface between two sheets. The vapour tends to evacuate through the keyhole and melt pool, particularly when no gap is present between the overlapped sheets. This causes process instabilities and results in the...

Microgalvanic corrosion of laser-welded HSLA steels

Laser welding of galvanized high strength low alloy (HSLA) steels leads to the evaporation of zinc at the weld and the formation of a heat-affected-zone (HAZ). High heat input due to welding generates macro galvanic coupling between the weld and the parent metal as well as micro galvanic corrosion at different microstructures of the weld, HAZ...