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The Ni-base superalloy INC738LC is a precipitation strengthened alloy and is widely used in hot sections of gas turbine engines owing to its excellent high-temperature strength and high hot corrosion resistance. The purpose of this study is to determine the appropriate welding current of Ni-base superalloy INC738LC after two passes of applying the tungsten inert gas (TIG) welding technique.

Ni-base superalloy INC738LC plates were joined by TIG welding technique by varying the welding current (30, 40 and 50 A). Welded specimens were investigated using optical microscopy, tensile tests, Vickers’s micro-hardness tests and X-ray diffraction (XRD). Optical microscopy was used to characterize fusion zone, heat-affected zone and base metal. Tensile test was conducted to characterize weld strength by determining ultimate tensile strength. Scanning electron microscopy was used to investigate the fracture surfaces after tensile tests. Micro-hardness test was conducted to characterize the welded joint. XRD was applied to determine precipitates formed after welding.

The ultimate tensile strength results show that the optimum weld current out of the three weld currents was found to be 40 A, which is the closest to that of the base metal.

Many researchers have worked to optimize welding parameters such as current and speed from the microstructural observations and mechanical properties of welded joints. The optimum weld current out of the three weld currents was found to be 40 A.

Titanium (Ti) alloys are in high demand in manufacturing industries all over the world. The property like high strength to weight ratio makes Ti alloys highly recommended for aerospace industries. Ti alloys possess good weldability, and therefore, they were extensively investigated with regard to strength and metallurgical properties of welded joint. This study aims to deal with the analysis of strength and microstructural changes in Ti-6Al-4V (Grade 5) alloy after tungsten inert gas (TIG) welding.

Two pair of Ti alloy plates were welded in two different voltages, i.e. 24 and 28 V, with keeping the current constant, i.e. 80 A It was a random selection of current and voltage values to check the performance of welded material. Both the welded plates were undergone through some mechanical property analysis like impact test, tensile test and hardness test. In addition, the microstructure of the welded joints was also analyzed.

It was found that hardness and tensile properties gets improved with an increment in voltage, but this effect was reverse for impact toughness. A good corroboration between microstructure and mechanical properties, such as tensile strength, hardness and toughness, was reported in this work. Heat distribution in both the welded plates was simulated through ANSYS software to check the temperature contour in the plates.

A good corroboration between microstructure and mechanical properties, such as tensile strength, hardness and toughness, was reported in this study.

The development of a vision‐guided robot for TIG welding is being claimed as a breakthrough by Meta Machines. Brian Rooks reports on a system to weld rocket motors for a Swedish company.

New markets are being opened up for the products of Meta Machines, the UK advanced robot systems company. Brian Rooks reports on development in weld seam tracking and electronic assembly.

Ingersoll‐Rand Professional Tool Group's new slimline 3BL1 air drill is said to be ideal for close quarter drilling in confined spaces where minimum side to centre distance is available. The drill is only 29 mm (1.25 in) in diameter and 185 mm (7.25 in) long.

The Aero Tach Divsion of Consolidated Instrument Company announces the TSO‐C49A — F.A.A. authorisation for the new electric “Twin Tach” Model 8010.

The primary objective of this investigation is to optimize the constricted arc tungsten inert gas (CA-TIG) welding parameters specifically welding current (WC), arc constriction current (ACC), ACC frequency (ACCF) and CA traverse speed to maximize the tensile properties of thin Inconel 718 sheets (2 mm thick) using a statistical technique of response surface methodology and desirability function for gas turbine engine applications.

The four factor – five level central composite design (4 × 5 – CCD) matrix pertaining to the minimum number of experiments was chosen in this investigation for designing the experimental matrix. The techniques of numerical and graphical optimization were used to find the optimal conditions of CA-TIG welding parameters.

The thin sheets of Inconel 718 (2 mm thick) can be welded successfully using CA-TIG welding process without any defects. The joints welded using optimized conditions of CA-TIG welding parameters showed maximum of 99.20%, 94.45% and 73.5% of base metal tensile strength, yield strength and elongation.

The joints made using optimized CA-TIG welding parameters disclosed 99.20% joint efficiency which is comparatively 20%–30% superior than conventional TIG welding process and comparable to costly electron beam welding and laser beam welding processes. The parametric mathematical equations were designed to predict the tensile properties of Inconel 718 joints accurately with a confidence level of 95% and less than 4.5% error. The mathematical relationships were also developed to predict the tensile properties of joints from the grain size (secondary dendritic arm spacing-SDAS) of fusion zone microstructure.

Presently, the materials used in light combat aircraft structures are aluminium alloys and composites. These structures are joined together through riveted joints. The weight of these rivets for the entire aircraft is nearly one ton. In addition to weight, the riveted connection requires a lot of tools, equipments, fixtures and manpower, which makes it an expensive and time-consuming process. Moreover, Al alloy is also welded using tungsten inert gas (TIG) welding process by proper control of process parameters. This process has limitations such as porosity, alloy segregation and hot cracking. To overcome the above limitations, an alternative technology is required. One such technology is friction stir welding (FSW), which can be successfully applied for welding of aluminium alloy in LCA structures. Therefore, this paper aims to compare the load carrying capabilities of FSW joints with TIG welded and riveted joints.

FSW joints and TIG welded joints were fabricated using optimized process parameters, followed by riveted joints using standard shop floor practice in the butt and lap joint configurations.

The load-carrying capabilities of FSW joints are superior than those of other joints. FSW joints exhibited 75 per cent higher load-carrying capability compared to the riveted joints and TIG-welded joints.

From this investigation, it is inferred that the FSW joint is suitable for the replacement of riveted joints in LCA and TIG-welded joints.

Friction stir butt joints exhibited 75 per cent higher load-carrying capability than riveted butt joints. Friction stir welded lap joints showed 70 per cent higher load-carrying capability than the riveted lap joints. Friction stir butt joints yielded 41 per cent higher breaking load capabilities than the TIG-welded butt joints. Moreover, Friction stir lap weld joints have 57 per cent more load-carrying capabilities than the TIG-welded lap joints.

The paper aims to report on a new welding technology, TIP TIG.

The principle of operation and benefits of the technology are described together with a typical application.

The study finds that the technology provides the quality of TIG welding at the speeds of MIG welding, providing significant cost savings to the user.

TIP TIG provides a good opportunity for all users of robotic MIG welding to improve the quality of their product and reduce their costs.

The paper introduces a new and useful technology to the robot industry.