Grenzebach Friction-Stir Welding Effectively Seals Aluminum Parts
Perfectly sealed joints between aluminum and aluminum alloys are increasingly demanded by different industries, says Grenzebach. Friction-stir welding (FSW) solves this task with flying colors.
Grenzebach, headquartered in Hamlar, Bavaria, offers a portfolio of equipment adapted to this innovative joining technology and supports the customer-specific optimization of welding processes from planning to series production, the company says.
Tightness, tightness, tightness — this is a demand repeated by the aluminum processing industry. This property is indispensable for designs and components such as heat exchangers, battery trays or coolers, Grenzebach explains. Long-lasting, solid, fluid- and pressure-tight connections between the workpieces are therefore a must. If it is to be really tight, many manufacturers decided to use friction-stir welding. After all, FSW produces process-reliable seals relatively easily. Due to its typical high degree of automation, this modern joining technology can also be perfectly integrated into existing industrial series production.
Aluminum is Becoming Increasingly Popular
Friction-stir welding is a so-called solid-phase welding process that requires no melt, the experts explain. There are no pores or hot cracks that could threaten the quality of the joint as they would in conventional joining processes. It is precisely these effects that lead to leaks in conventional fusion welding, for example.
According to Grenzebach, this effect is intensified when aluminum casting material comes into play, which has become standard in many designs and components of liquid-cooled systems in the automotive, energy transmission/power electronics, battery manufacturing, rail vehicle construction, aerospace and consumer electronics sectors. Especially when joining aluminum and aluminum combinations, such as sheet and cast materials, the friction-stir welding process shows its strengths and produces high-quality joints and an excellent surface quality. Complex reworking steps such as deburring the weld seam could therefore become obsolete.
Creating a Fluid- and Pressure-Tight Connection
In friction-stir welding, a rotating, wear-resistant friction pin heats the material at the intended joints. The material is then plastically deformed and "stirred" along the joint by the friction pin — without reaching the melting point of the materials! The plasticized material is compressed by means of the tool shoulder, which creates the desired solid, fluid- and pressure-tight connection between the workpieces.
Compared to conventional fusion welding processes, such as arc welding, friction-stir welding requires neither a welding rod nor shielding gas or complex exhaust air systems, Grenzebach emphasizes. Furthermore, the process involves low vibration, noise and emissions and, of course, does not generate any optical radiation.
Grenzebach notes that welding is often the last step in the process chain. If errors occurred during this phase, the entire product is ready for scrap. Anyone who invests in FSW technology therefore relies on a secure completion of their process chain. A superior process conclusion and the absolute tightness of the product, which can be achieved simply in a highly reproducible way, are the result: These aspects alone make the purchase of an FSW system quickly pay off, they say.
Joining with Minimum Idle Times
According to Grenzebach, the ever-shorter cycle times of FSW technology meets the high production volumes in numerous industries. In addition to reducing the welding times, it is also important to reduce all non-productive times to a minimum in order to save valuable cycle time. For this purpose, the repositioning of components and the loading and unloading of the machines are fully automated. The new FSW machine generation DSM 1400 & DSM 2400 from Grenzebach is modular and can be complemented with various component feeding systems. Thanks to the two movable prestressing units of the systems, the second device can be exchanged in parallel during the welding process. The machines could thus continuously weld and reduce idle times to a minimum.
As a system integrator and supplier of friction-stir welding systems with many years of experience, Grenzebach provides complete FSW process solutions for industrial series production. Grenzebach's holistic approach includes not only the welding system and the supply of welding equipment but also process development for the respective customer application and the provision of adapted stirring tools.
This article was first published by blechnet