Tensile Strength Of Weldments Research Articles

Finite Element Simulation of Friction Stir Welding of Inconel 718 to Nimonic 80A

This paper presents results of simulation of friction stir dissimilar welding of 5 mm thick, Nickel-based super-alloys, Inconel 718, and Nimonic 80A using Abaqus software. Four different trials were done to understand the influence of tool rotation speed on temperature distribution in weld zone while travel speed remains constant. The temperature in the weld zone was found to increase with the increase in tool rotation speed and travel speed. The temperature on the advancing side of the tool was higher than that of the retreating side. The tensile strength of weldment was found, by simulation, to be 25% more than that of base metal, Inconel 718. This may be due to grain refinement and dynamic recrystallization during FSW. The simulated bend test revealed an adequate level of ductility of weldments.

An examination of mechanical properties of dissimilar AISI 304 stainless steel and copper weldment obtained using GTAW

In this study of examination, the mechanical properties of AISI 304 stainless steel and copper fabricated by gas tungsten arc welding process (GTAW) are evaluated. Dissimilar material welding of AISI 304 stainless steel and copper are chosen in the industry because of their high tensile strength, hardness, good corrosion resistance and high electrical or thermal conductivity. The copper is difficult to welding because of high thermal conductivity which in turn tends to dissipate heat rapidly away from the weld leading to difficulties in reaching the melting temperature. In addition, high thermal expansion meaning that distortion can occur during welding. Due to the differences in material properties, there is uneven partitioning of the heat at the joint interface in dissimilar welding. To compensate for heat loss at the interface between these weld pads the heat source or welding torch was traversed at an off-setting distance toward copper. The purpose of this study is to evaluate the mechanical properties of the dissimilar weldment using gas tungsten arc welding (GTAW) for AISI 304 SS and copper with 1.25 mm offsetting distance. To reveal the effectiveness of the proposed scheme the mechanical properties in terms of micro-hardness and tensile strength of weldment are evaluated for the weldment viz-a-viz copper.

Characteristics of fiber laser weldments of two phases (α+β) titanium alloy

Laser welding experiments are conducted at various welding conditions on Ti-6Al-4 V alloy plates by employing fiber laser. A special type of workpiece fixture having provision of supplying shielding gas is fabricated for the protection of weld bead efficiently from environmental contamination. The influence of process parameters i.e. welding speed on the development of non-homogeneous microstructure of the weld bead is investigated by conducting microstructural characterization in details. Different morphologies of martensitic phase such as α´martensite, massive αm, blocky α and basket-weave structure are observed in the fusion zone. The variation in amount of α´ martensite is observed within heat affected zone. The calculated cooling rate and microstructure evaluation in the fusion zone are consistent with the continuous cooling transformation curve of Ti-6Al-4 V alloy. Higher hardness is found in fusion zone of the weldments. At lower welding speeds (500 ̶ 600 mm/min), underfill weld defects and at higher welding speed (800 mm/min) the micro-pores are observed in the weld bead. However, sizes of micro-pores are within the acceptable range as per BSEN: 4678 European standard. The microhardness and tensile strength of weldments are increased with increasing welding speed due to the development of finer α´ martensite in the fusion zone. For a fixed beam power of 1200 W, the most favorable range of welding speed (700 ̶ 800 mm/min) is identified which produced consistently high quality welds without crack and acceptable pore size. Vickers microhardness and tensile test results indicate that the optimal process parameters obtained in the current study can be suitably used in industries.

Effect of Pulsed Current on TIG Weldmentsof Aluminium Alloy (5052) and Alloy Steel(EN24)

In this experimental work destructive and non-destructive tests have been carried out on an aluminium alloy(5052) and alloy steel of EN24 using GTAW with pulsed and non-pulsed current at different frequencies 3Hz 5Hz,&7Hz.The Liquid Penetrant, radiography and tensile strength of weldments were evaluated and compared with pulsed and non-pulsed current welding at different frequencies of two materials (5052 aluminium alloy of 2.5mm thick and alloy steel EN24 of 4.5 mm thick).The aim of this experimental work is to see the effect of pulsed current on the quality of weldments. The experimental results pertaining to different pulsed current welding for the above materials using pulsed and non-pulsed current GTAW are discussed and compared

Al6082-T6의 MIG용접부에서 입열량에 따른 열영향부의 연화와 인장특성에 관한 연구

Al6082-T6 is widely used because of its corrosion resistance and excellent strength. HAZ softening occurs in MIG welding process for this aluminium alloys because this aluminium alloy is heated to higher temperature than its aging temperature during welding. Therefore, low heat input and minimum standard deviation of heat input are required for narrow HAZ width and, for higher strength of welds. In this study, Al6082-T6 was used to examine for HAZ softening with various heat input in aluminium MIG welding. For weldments, micro hardness was measured and tensile test was carried out. Minimum hardness was increased at high speed welding such as 80cm/min and 120cm/min in welding speed comparing with 40cm/min. Also, in case of high speed welding such as 80cm/min and 120cm/min, tensile strength of weldments was increased about 10% comparing with low speed welding(40cm/min).

An investigation of microstructure/property relationships in dissimilar welds between martensitic and austenitic stainless steels

Abstract The metallurgical characteristics, tensile, hardness, toughness and corrosion resistance of dissimilar welds between X5CrNi18-10 grade austenitic and X20CrMo13 grade martensitic stainless steel have been evaluated. Both austenitic and duplex stainless steel electrodes were used to join this combination, using multipass manual metal arc welding process. Defect free welds were made with each welding consumable. It was found that the tensile strength of weldment, which was produced by duplex electrode (E2209-17), was slightly lower than that of austenitic electrode (E308L-16). The toughness of the both E2209-17 and E308L-16 deposits was acceptable even at low temperature regardless of heat input. Hardness was increased in both welds made with E2209-17 duplex and E308L-16 austenitic electrode along the X20CrMo13/weld metal fusion boundary due to heat annealing and then following high cooling rate. The pitting corrosion resistance of the weld metal made with E308L-16 and E2209-17 filler metal was found acceptable. Although, heat affected zone in the weldment and X20CrMo13 base metal were affected by electrolytic corrosion. This investigation has shown that both filler metals can be used to join austenitic stainless steel to the martensitic stainless steel.