Super Magnesium: the next big thing?
Allite's Super Magnesium alloy is claimed to be the most advanced form of a metal that has long looked attractive to the cycling industry, but has yet to gain broad acceptance. Could this be the tipping point?
A few days prior to Interbike this year, a press release went out from Allite, a company that manufactures a product named Super Magnesium. This new magnesium alloy for the bicycle industry would be launched at Interbike. Few, if any, knew much about the company, so the news came like a bolt from the blue. Interest and attention since then has been considerable, because if the material is everything they say it is, frame-wise we're looking at something that potentially weighs similar to carbon fiber, can be built into a lively-feeling frame, but won't cost you an arm and a leg.
Allite is based in Dayton, Ohio, and like its sister company, Huffy, is owned by the Hong Kong-based investment consortium United Wheels Ltd, which purchased Niner Bikes earlier in 2018. United Wheels is reportedly in for the long-haul with the intention of becoming a house of brands, with a particular interest in the high-end of the cycling market.
Development work on the Super Magnesium material began in 2006, and initially use was only in military and aerospace applications. As the material matured the cost started to come down, and now is at a point that's commercially feasible in a wide range of industries, including bicycles.
Allite is offering three different magnesium alloys, AE81, ZE62, and WE54. Generally speaking you could say A = Aluminium, E = Rare-earth elements, Z = Zinc, and W = Yttrium. For a more precise breakdown of WE54, visit AZoM, but the two former alloys are not listed on that or the American Society of Metals site. Again in broad terms, each alloy is best suited for three different methods: welding, forging and casting. The numerals indicate the percentage of each alloy combined with the magnesium, so AE81 is eight percent aluminium, and one percent rare-earth elements. AE81 is the alloy to be offered in frame tubes.
Morten Kristensen, Allite's director of product and marketing
Exactly which rare-earth elements is not disclosed, but according to Morten Kristiansen, the product and marketing director of Allite, these make a significant difference to factors such as the safety and durability of the Super Magnesium.
Asked about the likelihood of the bicycle brands owned by United Wheel using Super Magnesium products, Mortensen said there are no specific plans to do so at present, although he hinted that some prototyping might be forthcoming at Niner to gauge overall suitability. Allite itself, despite being physically close to Huffy's design headquarters, intends to be solely a supplier of frame tubes and metal for making components.
They're not just talking tubes. Pictured: seat post, suspension linkage, rim section
Naturally the talk among frame builders focused on the frame tubes, but the position of Allite is that Super Magnesium can be used to make almost everything on a bicycle that aluminium presently does: cranks, rims, suspension arms, seat tubes, headstems, bottom bracket shells, calipers, levers, although there is still a questionmark about handlebars. Conversations with Shimano and SRAM are already taking place, according to Allite president Bruno Maier, and Shimano representatives were seen a the Allite booth during the show.
The bicycle frames on display at Interbike, made purely to show the tubing, employed extruded magnesium pipe with a butting profile of 2.0-1.2-1.8 (mm). Double butted variations are also available. The main triangle tubes of the display bikes were butted, while the stays were straight gauge. "We should be able to butt the smaller tubes as well if the demand is present," said Mortensen. The rare-earth minerals reduce the combustibility of its dust and shavings, as well as causing micro-oxidation to increase the resistance to corrosion.
“We have completed thousand-hour salt spray tests without seeing any corrosion. The Ford motor company has conducted similar tests, because they use our material unpainted in some of their models,” said Kristiansen.
Another feature Kristiansen points out is that it uses less energy during production than steel. The raw material is softer so cuts faster and wears less on equipment, although the finished frame will require heat treatment. Allite recommends T5 heat treatment.
A frame builders’ existing TIG welding equipment can be employed, using a magnesium welding rod. The company envisions running training courses for frame builders who don’t yet have magnesium welding experience.
Super Magnesium gravel bike on display at Interbike.
The pictured frame approximates to a 52cm seat tube size and weighs 940g/2lbs. Kristiansen says the tubes used in the frame have passed the ISO requirements for mountain bike tubing. The tubes have not yet been tested to EN standards or those for Australia and Japan.
The vibration absorbtion is said to be roughly on a level with carbon composites, and is about 20 times greater than aluminium. By using the different alloy formulas mentioned above, Allite can change the mechanical properties such as strength, compliance and elongation. The elongation, or ductility, is considerable, with close to 20 percent elongation possible. This makes the ZE62 well suited to 3-D forging, Kristiansen points out.
Pricing has not yet been set, but Kristiansen says it will be a lot less expensive than carbon fiber, and the tubing product is expected to be available to frame builders in small orders at a price well below that of premium steel. The look of the frame tubes and joints will be similar to that of an aluminium frame with thick, oversize tubing that has similarly oversize welding beads. The NAHBS award-winning Paketa tandem might give a better indication of how the joints will look than do the frames Allite took to Interbike.
2012 NAHBS award-winning Paketa tadem, anodized red. Photo: Paketa Bicycles.
Fatigue resistance is an issue with this class of materials. Allite uses a PEO treatment (plasma electrolytic oxidation) of Super Mag, which according to their information produces ceramic layers on the surface of light alloys. PEO surface coatings, they write, increase wear resistance, corrosion resistance, and both thermal and chemical stability. Bruno Maier reports that one of the early prototype frames they made has stood up well over a span of several years' riding, although he says they do not yet have hard data on how fatigue failures would occur.
As for how a magnesium frame can ride, Nick Wigston, marketing manager for Zinn Bicycles and the now-defunct Paketa is a fan. "I have a Paketa magnesium 'cross bike. I love it. Had it for a couple of years now and I ride it a lot. It's a great material. Stiff, but compliant, not harsh like aluminum can be, but it's not springy like titanium. It's responsive. When you push on the pedals, it's bam! Let's go! It has a pop that you don't get with carbon."
The reasons Paketa closed its doors, said Wigston, were entirely personal. He noted though, that Paketa had some issues when power-coating frames because it found out that corrosion could develop under powdercoat paint. Because of the PEO treatment, the same is not expected to apply to Super Magnesium.
Chainstay cutaway showing different Super Magnesium frame elements
Also significant is that Paketa used a different alloy, AZ61. Lennard Zinn, who used the same alloy in many frames he sold over the years, recalls that brittleness, or low elongation, was an issue. But this he noted, seems to have been addressed in the Super Mag alloy. A bigger concern facing small frame workshops, says Zinn could be the need to heat treat the tubes. "Heat treatment complicates the process excessively if you're not doing this on a big scale," he wrote in a text message.
Indeed, the initial reaction from the frame building industry has been mixed. Several different magnesium alloys have shown up over the years. Some may recall that the frame builder and innovator Keith Bontrager burned down his garage while making a magnesium yoke for suspension forks around the early ‘90s. At a similar time Kirk Precision made a cast magnesium frame that stayed for a few years on the market, but by 2000 was very rarely seen.
In the early 2000’s the tubing manufacturer Reynolds Technologies offered a mandrel-butted magnesium tube. Keith Noronha of Reynolds recalls: “The strength-to-weight ratio was very good compared to existing materials at that time. Our frame build customers could weld magnesium safely, which needed care as the welding and heat transfer around the weld area can create some inconsistency in the weld zone, the magnesium tubing could be coated to reduce the corrosion impact and there are environmental benefits. Reports on the ride damping qualities were very positive as well.” In the end, though, Reynolds, decided to focus resources on its successful 853 and 953 tube sets, which have proved highly successful.
While all of the above have used different alloys and processes to the materials offered by Allite, the rolling eyes and mutterings of 'here we go again,' from the frame building industry are understandable. Magnesium holds lots of promise but has yet to fully deliver.
Frame builder/distributor Andrew Cooper of Frame Builder Supply visited the Allite booth at Interbike and was favorably impressed, to the point of hypothetical discussions with Allite about getting tube sets to frame builders for trial builds. In text and forum comments Cooper has echoed the remarks of John Tallerico of Nova Cycle Supply that this could be a tough sell to frame builders. That said, aluminum master Paul Sadoff of Rock Lobster seemed open to giving it a try.
While the frame builder response at this point is nothing more than casual conversation. It's clear that there is a cautious interest in the material.
By the 2019 NAHBS more will be known: about the company, the material and what the cycling industry thinks it might do with this material. But even if impressions then are very positive it is unlikely that Super Magnesium will appear on the market much before the end of 2019. Allite is considering taking a booth at NAHBS to display frames made by custom builders.
If Super Magnesium can create a strong, lightweight, corrosion-resistant frame that is attractive and good to ride, it is almost certain that some consumers will request it, particularly as it is a new thing. As well as this, some frame builders will likely choose to differentiate themselves by offering magnesium-tubed frames, even if heat treating is an obstacle. Or possibly, the material will prove most popular in bicycle components rather than frames. Many potential outcomes seem possible at this point, but based on the potential upside of a lightweight, durable material, that shouldn't come with a big step-up in price, and which could produce a great-feeling frame, it's well worth keeping an eye open for further news of Super Magnesium.