Effect of Tool Rotational Speed on the Tensile and Microstructural Properties of Friction Stir Welded Different Grades of Stainless Steel Joints

Abstract

Friction stir welding is a relatively new solid state joining process, which is suitable for welding similar and dissimilar materials. The present research work concentrates on the effect of tool rotational speed on the tensile, microstructural properties and microhardness of the friction stir welded joints of different grades of austenitic stainless steel sheets. Four different tool rotational speeds are used in the experimentation while the other process parameters like traversing speed and the tool tilt angle are kept constant. The tensile testing, micrography and microhardness measurements were carried out in the welded samples. It is observed from the results of tensile testing that the joint made at the tool rotational speed of 1320 rpm has the maximum strength among the experimented speeds. The measured microhardness values at heat affected zone and parent metal zone have shown higher hardness than the weld zone. Fine and equi-axed grains are observed in the welded region at all experimented speeds with a negligible amount of transformation of austenite into martensite. These results have impact on the development of welding procedure for dissimilar stainless steel friction stir welding process.

Effect of Pin Geometry and Tool Rotational Speed on Microstructure and Mechanical Properties of Friction Stir Spot Welded Joints in AA2024-O Aluminum Alloy

“…It is interesting to note that at the bottom of the keyhole, a continuous decrease in the hardness is observed with increasing tool rotational speed, especially in FSSW prepared using step pin. It may be argued that the use of step pin produced more heat which results in coarsening the precipitates hence softening [21,34,35].…”

“…The quality characteristics of FSSW joints formed in the metal alloy are strongly influenced by design and welding parameters. One of the most important factors influencing the quality of the FSSW joints is the design of the tool used for producing the friction and stirring action [21]. It seems that research works related to the FSSW in AA2xxx series aluminum alloys have been studied extensively, but there have been limited published data on the influences of pin geometry and rotational speed on the microstructure and strength of the FSSW AA2024-O aluminum alloy joints.…”

Investigating the Effect of Considering Different Cross Section Design in Friction Stir Welded Joint Line of Dissimilar Aluminum Alloys

“…Thus, an appropriate joint design requires experience. Even having experience, trial welds are necessary before selecting the final joint configuration and welding parameters [7]. The term weld joint design can be defined as the way that two pieces of metal are put together or aligned with each other.…”

Control of Steel Detachment and Metal Flow on Aluminum-Steel Friction Stir Welding of thin Joints

“…The welding of dissimilar joints [17,18] was approached considering three different systems: i) dissimilar joints of low melting metals, ii) the joining of hard metals, and iii) the joining of metals with different mechanical properties. The welding of systems composed of metals with very different physical properties has limitations due to the multiple challenges.…”