Recently, the engineering field has undergone a broad range of innovations that have resulted in novel manufacturing techniques that are considerably more efficient in relation to performance and energy consumption compared to traditional techniques.
Potentially, design engineers—the people behind the design and fabrication of each and every complex structure and device people come across and use in their everyday lives—are the professionals most affected by such developments.
Engineering innovations such as these are always imminent since design engineers are always more concerned about the optimal utilization of financial and material resources, as well as the overall quality of their inventions. This suggests that it is necessary for professional engineers to continuously update themselves with the latest developments in their field, to achieve perfection in their projects, and to meet the required standard.
This article analyzes a mechanical welding technique that has gained considerable attention in the recent times and discusses the way engineers at Elon Musk’s aerospace manufacturing company, SpaceX, have used it in their recently launched Falcon Heavy rocket.
How Does Friction Stir Welding Work?
Friction stir welding (FSW) is a welding method devised by The Welding Institute Ltd. in the year 1991. Despite the fact that it was developed more than 25 years ago, it has seen a quick increase in demand in the past few years, specifically due to the increase in the demand for higher strength and durability requirements in modern engineering applications.
It is a unique method of combining metals with each other, which is largely different from conventional methods such as gas welding or arc welding. The fact that it is a solid-state welding technique makes it unique, suggesting that neither of the materials being combined are melted.
Rather, they are simply softened to an extent that they can penetrate each other’s surface with a little help. This method produced exceptional mechanical properties such as fatigue strength and stiffness, as well as negligible defects in the weld region. Furthermore, this welding technique also reduces the wastage of materials and ensures an enhanced appearance, indicating lower surface finishing requirements. Lastly, one of the most lauded benefits is that it does not have any harmful effects on the environment since toxic fumes are not produced in the complete process.
How is Friction Stir Welding Performed?
FSW is carried out using a profiled welding tool, a clamp that holds the workpieces together, and a mechanical setup for guiding the tool along the joint line. These components operate in tandem to produce the weld joint.
The shape of the tool is analogous to that of a milling cutter, which rotates through the entire machining process and can be moved along the surface of the workpiece. At first, the tool is practically pushed into the joint line surface, and then, it traverses along the joint line periphery with the help of the welding machine. Heat is produced by the friction between this non-wear tool and the workpiece, thereby increasing the temperatures of the metals close to the joint line.
A profiled probe positioned at the very end of the tool is shaped such that it forces metals on both sides of the joint line into each other. They combine readily as the heat generated in the process at this point considerably softens them.
Friction Stir Welding and SpaceX’s Falcon Heavy
The outstanding qualities of this method make it specifically relevant to applications that mandate high-strength properties and harsh working conditions. One such example is the aerospace industry, where modern space vehicles are developed to endure unfathomable forces and temperatures.
Recently, SpaceX—the aerospace manufacturing company led by Elon Musk—has launched its Falcon Heavy rocket into space with a Tesla Roadster as the payload, which is the fourth-highest of all rockets developed to date with respect to load-carrying capacity, featuring the use of friction stir welding. This aspect underscores FSW’s significance in the aerospace industry and its probable application in future engineering applications.
SpaceX design engineers employed FSW to connect the break-off fuel tanks in their rocket, which have a vital role in the propelling of the spacecraft after it enters the space and settles in its orbit. The reason for this application was evidently the requirement of remarkable strength in break-off fuel tanks of such a powerful rocket, which cannot be fulfilled by traditional methods such as liquid-state welding or non-permanent joints like rivets.
Summarizing the points discussed in this article, it can be said that the future of welding is in the application of innovative methods such as the FSW, which are less expensive, highly efficient, and eco-friendly. It is the first choice for design engineers in search of permanent joining methods that offer better results compared to those being used at present.
This information has been sourced, reviewed and adapted from materials provided by Matmatch.
For more information on this source, please visit Matmatch.