Friction stir welding and processing. Abstract. Friction stir welding (FSW) is a relatively new solid- state joining process. This joining technique is energy efficient, environment friendly, and versatile. Friction Stir Welding (FSW) is a solid-state joining process that creates extremely high-quality, high-strength joints with low distortion. A non-consumable spinning. FRICTION STIR WELDING - researchgate.net PPT. Presentation Summary : INTRODUCTION. FRICTION STIR WELDING. FSW is a solid state joining process in which the material.In particular, it can be used to join high- strength aerospace aluminum alloys and other metallic alloys that are hard to weld by conventional fusion welding. FSW is considered to be the most significant development in metal joining in a decade. Recently, friction stir processing (FSP) was developed for microstructural modification of metallic materials. In this review article, the current state of understanding and development of the FSW and FSP are addressed. Particular emphasis has been given to: (a) mechanisms responsible for the formation of welds and microstructural refinement, and (b) effects of FSW/FSP parameters on resultant microstructure and final mechanical properties.
While the bulk of the information is related to aluminum alloys, important results are now available for other metals and alloys. At this stage, the technology diffusion has significantly outpaced the fundamental understanding of microstructural evolution and microstructure–property relationships. Keywords. Friction stir welding; Friction stir processing; Weld; Processing; Microstructure. Introduction. The difficulty of making high- strength, fatigue and fracture resistant welds in aerospace aluminum alloys, such as highly alloyed 2. XXX and 7. XXX series, has long inhibited the wide use of welding for joining aerospace structures. These aluminum alloys are generally classified as non- weldable because of the poor solidification microstructure and porosity in the fusion zone. Also, the loss in mechanical properties as compared to the base material is very significant. These factors make the joining of these alloys by conventional welding processes unattractive. Some aluminum alloys can be resistance welded, but the surface preparation is expensive, with surface oxide being a major problem. Friction stir welding (FSW) was invented at The Welding Institute (TWI) of UK in 1. The basic concept of FSW is remarkably simple. Friction Stir Welding (FSW), invented by Wayne Thomas at TWI Ltd in 1991, overcomes many of the problems associated with traditional joining techniques. Presentation on Friction Stir Welding by ganeshkhavi in Types > Presentations. Start your free trial and access books, documents and more. Rotary Linear Stir MTI is a Full-Service Solutions Provider specializes in: A non- consumable rotating tool with a specially designed pin and shoulder is inserted into the abutting edges of sheets or plates to be joined and traversed along the line of joint (Fig. The tool serves two primary functions: (a) heating of workpiece, and (b) movement of material to produce the joint. The heating is accomplished by friction between the tool and the workpiece and plastic deformation of workpiece. The localized heating softens the material around the pin and combination of tool rotation and translation leads to movement of material from the front of the pin to the back of the pin. As a result of this process a joint is produced in . Because of various geometrical features of the tool, the material movement around the pin can be quite complex . During FSW process, the material undergoes intense plastic deformation at elevated temperature, resulting in generation of fine and equiaxed recrystallized grains . The fine microstructure in friction stir welds produces good mechanical properties. Fig. Schematic drawing of friction stir welding. FSW is considered to be the most significant development in metal joining in a decade and is a “green” technology due to its energy efficiency, environment friendliness, and versatility. As compared to the conventional welding methods, FSW consumes considerably less energy. No cover gas or flux is used, thereby making the process environmentally friendly. The joining does not involve any use of filler metal and therefore any aluminum alloy can be joined without concern for the compatibility of composition, which is an issue in fusion welding. When desirable, dissimilar aluminum alloys and composites can be joined with equal ease . In contrast to the traditional friction welding, which is usually performed on small axisymmetric parts that can be rotated and pushed against each other to form a joint . The key benefits of FSW are summarized in Table 1. Table 1. In this case, a rotating tool is inserted in a monolithic workpiece for localized microstructural modification for specific property enhancement. For example, high- strain rate superplasticity was obtained in commercial 7. Al alloy by FSP . Furthermore, FSP technique has been used to produce surface composite on aluminum substrate . In a relatively short duration after invention, quite a few successful applications of FSW have been demonstrated . In this paper, the current state of understanding and development of the FSW and FSP are reviewed. Process parameters. FSW/FSP involves complex material movement and plastic deformation. Welding parameters, tool geometry, and joint design exert significant effect on the material flow pattern and temperature distribution, thereby influencing the microstructural evolution of material. In this section, a few major factors affecting FSW/FSP process, such as tool geometry, welding parameters, joint design are addressed.
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