Could treated wood replace steel and titanium? Engineers at the University of Maryland in College Park say they have developed a way to make wood strong enough to give titanium alloy a run for its money.
“This new way to treat wood makes it twelve times stronger than natural wood and ten times tougher,” said Liangbing Hu, research team leader. “This could be a competitor to steel or even titanium alloys, it is so strong and durable. It’s also comparable to carbon fiber, but much less expensive.”
“It is both strong and tough, which is a combination not usually found in nature,” said Teng Li, the co-leader of the team. “It is as strong as steel, but six times lighter. It takes 10 times more energy to fracture than natural wood. It can even be bent and molded at the beginning of the process.”
The process involves removing the wood’s lignin, then compressing the wood under mild heat, causing the cellulose fibers to become so tightly packed that they form strong hydrogen bonds. The compression makes the wood five times thinner than its original size.
“This kind of wood could be used in cars, airplanes, buildings – any application where steel is used,” Hu said.
The study was published in the journal Nature.
Titanium is highly valued in the metals industry for its high tensile strength, as well as its light weight, corrosion resistance, and ability to withstand extreme temperatures. It’s as strong as steel but 45% lighter, and twice as strong as aluminum but only 60% heavier. Its ability to withstand extreme temperatures is a real technical advantage for many applications, but it presents serious challenges for titanium sheet producers. Thickness reductions require very high forces; sheet metal thickness measurement tools and on-line thickness gauges are essential for process optimization. As much of a challenge as this material is to roll, you don’t want to do it twice.
Steel is also widely-used for its strength as well as flexibility. It is flexible in the mechanical sense, but also in terms of the wide varieties of applications where it can be used. There are hundreds of different grades, thicknesses, and strengths of stainless steel, which are created by alloying steel with different elements. Martensitic or semi-austenitic steels are the strongest due to the addition of elements such as aluminum, copper and niobium.
Steel starts out as flat sheet metal or plates and must be manufactured to precise thickness specifications depending on the application for which it is used. It must also be easily machinable so that it can be formed into its permanent shape without cracking. While strength is an advantage in many applications, adding strengthening alloys may contribute poor machinability. Accurate thickness measurement of process-line steel ensures the finished products have specific mechanical properties, including the appropriate strength and stiffness for their application. An excellent way to accomplish this is by processing the material through a cold rolling mill. Cold rolling is a metal forming process in which a sheet of metal is pressed through a pair of rolls to reduce thickness, increase strength, and improve surface finish. Modern cold rolling mills are able to achieve high speed production of sheet steel with the help of an x-ray thickness gauge. These metal x-ray thickness gauges can detect and correct deviations in thickness in real-time to achieve high quality steel strip.
Read Optimization of a Cold Rolling Mill with a High Speed X-ray Thickness Gauge.
Rich Kovaly says
this is all fine and dandy, but the whole reason of using steel in the first place is because for one it’s stronger than wood but for two because of deforestation issues, and the simple fact that we need our trees I to survive. You know the whole carbon dioxide oxygen thing?
If you’re going to go back and start using wood to replace steel again then you’re going back to the old practices of using too much wood, which leads to supply and demand and lear cutting and deforestation again. Which I thought we had been trying to eliminate for the last 20 years
Angelo Lubag says
I see Rich Kovaly’s point clearly. However, if industry and government will see this clearly, mining ores (which destroys the environment) could be minimized. Also, it should trigger the business of reforestation since it could make a money making sense to grow much more wood. Governments should encourage it in that sense. We have so much steel to recycle to reduce mining and so much land that we deforested to plant again for future structures. If businesses will just cut old growth trees, then it wont be sustainable…
Angelo Lubag says
I see Rich Kovaly’s point clearly. Steel cannot be supplanted by this technology for the most part. However, if industry and government will see the advantages of this tech clearly, mining ores (which destroys the environment) could be minimized. Also, it should be used to trigger the business of reforestation since it could make a money making sense to grow much more wood. Governments should encourage it in that sense. We have so much steel to recycle to reduce mining and so much land that we deforested to plant again for future structures. If businesses will just cut old growth trees, then it wont be sustainable…
Theocrates Eustacius says
The point is to use fast growing soft species and leave old growth hard woods alone. Although not mentioned, this process can probably be used to transform bamboo, which grows like a weed, so to speak. Because these materials are stronger and lighter than steel, they may be substituted in many uses, such as biodegradable vehicles. It does not require much imagination to realize complex shapes can be molded using progressive dies or complex molds pressed using steam. Next step is to apply 3-D printing technology to these “plasticized” soft wood feedstocks.
Chris Hale says
Most wood that is used commercially in the US comes from specially bred trees that grow in a couple years, and they harvest the areas so as not to cut the whole thing down. I’m sure other countries don’t all do that, but the US has become pretty sustainable in the way we do that. If you compare a modern 4×4 to one from 40-50 years ago, you can immediately tell the difference. The modern ones are much lighter and more flimsy, almost like balsa wood in comparison
If the wood ends up compressed and used in buildings for decades (or more), it is also a good carbon sink. I wonder how much energy this process requires compared to the energy needs for steel?
Jamie Thompson says
Very interesting, but is it fire and mold resistant?
Wait until major league baseball finds out about this. Routine warning track fly balls will become home runs.