The future of the automotive welding industry could very well be magnesium alloys.
Magnesium is the lightest metal there is (it's 4 times lighter than steel) and it's also extremely easy to source. Thus, researchers at world's leading research facilities are working hard to develop Magnesium alloys that can be used in industrial applications, namely the automotive and aerospace industries.
The relation between vehicle weight and energy efficiency is a strong one: for every one hundred kilograms that you take away from a vehicle's total weight, you can boost it's fuel efficiency by approximately 3.5 percent.
So Magnesium alloys are incredibly auspicious when it comes to light-weighting vehicles but there's still a long way to go. Let's have a look at some recent developments regarding the development of viable magnesium alloys, specifically a one-day event at the University of Waterloo (Canada's leading University for Science and Technology) as well as ongoing cutting edge research at Switzerland's École polytechnique fédérale de Lausanne.
The CAMJ Workshop
In January of 2018 the Center for Advanced Materials (CAMJ) at the University of Waterloo in Ontario, Canada held the "Auto21: Innovation Trough Research Excellence" workshop and symposium that brought together many of the world's leaders in automotive welding technology.
The focus of the one day event was on the lightweight vehicles of the future with magnesium alloys being seen as likely being the propitious material of the (near) future.
As the event's host and associate professor at Waterloo's Department of Mechanical and Mechatronics Engineering Adrian Gerlich pointed out, whereas the weight reduction achieved by replacing steel with aluminium is 40 percent, the effect of replacing aluminium with magnesium alloys would be a further weight reduction of up to 40 percent.
Gerlich was also careful to point out that welding with magnesium alloys definitely has its challenges. For starters, although it is substantially lighter than aluminium, magnesium alloys lack aluminium's rigidity. This means that stiffeners and stringers will need to be added to magnesium alloys. Also, magnesium alloys need to be formed at a much higher temperature than aluminium and steel if they are being used to make stamped parts.
Corrosion is also an issue as the oxide of magnesium has no protective effect. Then, of course, there is the challenges that the very act of welding magnesium alloys presents; as these materials can become quite porous, there is a high likelihood of cracking and other distortions.
Despite these obstacles, if there was one clear takeaway from the Auto21 event at the University of Waterloo it was that Magnesium Alloys do represent the way forward as far as light-weighting is concerned.
Ongoing EPFL Research
Researchers at Switzerland's leading research institute and engineering university in Lausanne, are working hard to understand how magnesium alloys behave at the atomic level and how to make these materials more pliable. Although it's the lightest metal in the world, pure magnesium is inherently hard to work with. The research at EPFL is aimed at making more malleable magnesium alloys that can then be used by car manufactures to make lighter and more fuel efficient vehicles.
Researchers at EPFL's state-of-the-art Laboratory for Multi scale Mechanics Modelling have developed models that can predict how magnesium behaves when it is combined with different elements in an effort to identify the composition of a magnesium based alloy that is deformation resistant and pliable enough that it can be used in industrial applications.
So far, EPFL professor William Curtin has noted that the laboratory has had success in making magnesium more pliable by adding rare-earth metal like cerium and yttrium in addition to calcium and manganese do make magnesium sufficiently malleable. The problem with yttrium and cerium, however, is their scarcity and so the search for a cost effective method of creating magnesium alloys that can be used for large scale industrial applications continues at EPFL and other leading research facilities.