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This research explores friction stir welding (FSW) to examine the mechanical characteristics and microstructure of thick plates manufactured from the Mg-8Al-0.5Zn alloy. Applying the FSW procedure to warm-form an Mg-8Al-0.5Zn alloy for the differential case covering the gears in the car’s automotive technology. Weld quality was significantly improved after using response surface methodology (RSM) to examine various welding parameters and find the best configurations. Improved grain refinement and phase distribution in the weld zone were found in the microstructural study of 11.5 mm thick magnesium alloy plates using RSM-optimized parameters. By dynamic recrystallization, the grain size was reduced to 16 μm, which is fifteen times smaller than the original material, thanks to the good results of single-pass FSW welding.

EVs are a fast-growing market and appear as a promising option against the high emission of gasoline and diesel vehicles. The growth in the EV market has been decent and a regular buyer is still skeptical due to fire incidents occurring with EVs. Complex electronics, improper thermal management, mechanical abuse, improper cell grading activities and control in production, lack of testing in a production plant, and of course, uneven degradation of cells can be one of the reasons this promising technology is facing thermal runaway and in turn, the wrath of the government and public alike. One of the reasons thermal runaways can be triggered after a cell catches fire is because a part of heat travels via busbars to the neighboring cells, as the busbars can conduct heat faster than the air. For the heat that is conducted, it is easily understandable that we need to break the electrical, as well as thermal conduction connection to the neighboring cells.

To meet different target of light-weighting, lower fuel economy, crash safety and emission requirement, advanced high strength steel (AHSS) is commonly used in automotive vehicles and has become popular now a days. AHSS material up-to 1500 MPa is commonly used for structural components and major reinforcement of automotive BIW. Manufacturing of AHSS material requires precise control of chemical composition, and subsequent rolling and heat treatment to get optimum combination of required phases In most of the AHSS material microstructure, martensite is present along with ferrite or other phases. Hot stamp steel with strength level 1500 MPa strength also have martensite phase in microstructure after press hardening. However during heating and cooling cycle in resistance spot welding, martensite phase tempering affects hardness at Heat Affected Zone (HAZ).

Light weight and Robust manufacturing technologies are always needed for transformation drive in the Automotive industry for the next-generation vehicles with greater Power to weight ratio. Innovations and process developments in materials and manufacturing processes are key to this light weighting transformation. Aluminium material has been widely used for these light weighting opportunities. However, aluminum joining techniques, characterized by their poor quality and consistency are limiting this transformation. This technical paper represents one of such case, where the part is made up of Aluminium through conventional casting route which has affected the laser weld quality due to poor casting soundness. This experiment explains in detail about the importance of Casting soundness for laser weld quality, weld penetration, strength etc., and the Product consistency.

Nowadays, friction welding is recognised as a highly productive and economic joining process for similar as well as dissimilar welding of automobile and aerospace components. Friction welding is the viable solution to offset the challenges of dissimilar fusion welding due to varying thermal and physical properties as well as limited mutual solubility. This study investigated interface microstructure and bonding strength of dissimilar rotary friction welding of 3.15 mm E46 plate and 45 mm AA6061-T6 rod. The direct drive rotary friction welding of E46 and AA6061-T6 is performed at combinations of two different friction times (4 sec and 7 sec) and forging pressure (108 MPa and 125 MPa). Mechanical bonding strength at the interface is evaluated based on the push-off and multistep shear tests. Further, a fractured steel surface was visually examined to understand the failure mechanism of welded joints.

High strength aluminium alloys are an ideal material in the automotive sector leading to a significant weight reduction and enhancement in product safety. In recent past extensive development in the field of high strength steel and aluminium was undertaken. This development has been propelled due to demand for light weight automotive parts. The high strength to weight ratio possessed by Al alloy helps in reducing the total weight of the vehicle without effecting the overall performance, thereby increasing the fuel economy, and reducing the carbon emission level. Joining of high strength aluminium alloy is critical to develop durable automotive products. Joining of high strength aluminium alloy for mass production in automobile industry is a challenging task. Laser welding is recognized as an advanced process to join materials with a laser beam of high-power, high- energy density.

Cracks on metallic components may appear due to manufacturing, handling, installation, repair, welding etc. and are controlled by quality documents. However, if cracks violate the limit defined in quality document, then either parts will be scraped or will need additional evaluation through detailed fracture mechanic’s approach. The initial size and shape of a crack, part geometry and loading, highly impacts the behavior of a crack’s growth and remaining useful life. Industry standard software like ANSYS, AFGROW, Franc3D, etc. offer the solution to estimate the stress intensity factor and crack growth rate. However, these software’s have their limitation and start showing the deviation for complex geometry and loading scenario.

The stress concentration at welded joints and small crack propagation from some pre-existing discontinuities at notched regions control the fatigue life of typical welded structures. There are numerous FEM stress-based weld fatigue assessment approaches available commercially which unify FEM stresses with various fatigue software codes embedded with international weld standards. However, FEM stress-based approaches predict extensively conservative results. Considerable efforts & subjective decision making is required to arrive at desired level of weld life correlation with physical test results, in terms of weld life and failure location. This is majorly because of inconsistency & inaccuracy in capturing the hot spot stress results due to stress singularities occurring at the notched regions owing to the mesh sensitivity, modeling complexity.

Axles are a prominent part of automotive design. Along with a power transmission and differential system, axles support a vehicle’s weight and road-load reactions. Axles carry different attachments such as brakes and suspensions using brackets. Welds play an important role in design and longevity of bracket assemblies. Welds can be susceptible to fractures caused by intrusions akin to cracks and/or discontinuities, compounded by stress concentration due to weld profile and welding processes. Additionally, the simultaneous optimization of both brackets and welds remains a challenge with limited available methods. While topography or shape optimization techniques can enhance bracket robustness by minimizing compliance as the objective, this approach might inadvertently elevate the likelihood of weld fracture if weld dimensions are not concurrently updated.

Manufacturing processes such as casting, welding and additive manufacturing (AM) are prone to internal porosity and high surface roughness on the manufactured parts. These defects are inherent in the process and cannot be completely eliminated. Handling, transportation and maintenance of manufactured parts can also lead to defects such as scratches and dents due to abusive loads. The defects can be characterized in a number of ways, assuming they resemble a U-notch or V-notch, elliptical pores, or a continuous distribution of consecutive defects in combination with surface roughness. The designer utilizes existing analytical and empirical equations to predict stress concentration due to presence of various types of defects and compute factor of safety to ensure structural integrity of design subjected to various load cases. The applicability of existing analytical and empirical equations is studied, and modifications are suggested to improve the predictions.

The recent demand for power generation capability has raised the operating temperature of the power plants in the range of 600°C. High operating temperature leads to material degradation or reduced lifespan of boilers, which necessitates the analysis of the high-temperature behavior of welded joints of power plant boilers for a long lifespan and improved efficiency. Gr91 martensitic and SS304 austenitic stainless steel are identified as the primary piping material for these boilers. The boiler piping involves similar weld joints (Gr91/Gr91 and SS304/SS304) and dissimilar weld joints (SS304/Gr91) known as transition joints. These joints are exposed to high temperatures for a long duration during their service and it is therefore necessary to evaluate the high-temperature behavior of these weld joints. The hot tensile test is a short-term high-temperature test that serves as a valuable tool for analyzing the high-temperature behavior of the welds.

This specification covers a low-alloy steel in the form of welding wire.

This specification covers a corrosion- and heat-resistant nickel alloy in the form of bars, forgings, and flash-welded rings up to 4.00 inches (101.6 mm), inclusive, in nominal thickness or distance between parallel sides and having a maximum cross-sectional area of less than 12.6 square inches (81 cm2). Stock for forging or flash-welded rings may be of any size and condition as ordered.

This specification covers an aluminum alloy in the form of extruded profiles (shapes) 0.500 to 1.500 inch (12.7 to 38.1 mm), inclusive, in nominal thickness, and having a maximum cross-sectional area of 20 square inches (129 cm2) and a maximum circle size of 10 inches (254 mm) (see 8.7).

This specification covers a corrosion- and heat-resistant nickel alloy in the form of rods and wire.

This specification covers a corrosion- and heat-resistant nickel alloy in the form of welding wire.

Abstract This study investigated the influence of high-strength low-alloy steel on the fatigue life of a load-bearing member with a non-load-bearing transverse welded attachment (T-joint). It compared high cycle fatigue data to two fatigue design codes, namely BS 7608 and Eurocode EN 1993-1-9. Different base and filler material combinations of varying material strengths were investigated, resulting in a total of three different specimen configurations. Two material combinations had a high-strength steel (Strenx® 700 MC D) for the base material, with one combination having a matched filler material and the other having an undermatched filler material. The third material combination had a lower-strength steel (S 355 JR AR) for the base material, with a matched filler material. Tensile tests were performed to confirm the base material mechanical properties and weld quality of the manufactured specimens.

This specification covers a corrosion- and heat-resistant nickel alloy in the form of welding and additive manufacturing wire.