When most people think about strong materials they tend to put steel up there; steel is definitely stronger than wood. But now scientists have developed a way to make wood stronger than steel. In an article published in the scientific journal, Nature, a group of scientists has put forward the way in which wood can be made stronger than steel.
These researchers are now sharing the method that they have come up with to make wood a much stronger material. But just how much stronger could wood get?
How Strong Can Wood Get?
This new find could be key in reducing the overall costs of construction as wood is cheaper than steep and a natural material, to boot.
But, will wood ever get as strong as steel? We now know that thanks to the research published on Nature wood could become as sturdy as many as ten times stronger thanks to a process that involves first a chemical treatment and then heated compression. The result of this process, scientists have found, will be the creation of new chemical bonds which would make the wood at least ten times stronger. Wood that strong could potentially be used in the construction of vehicles and buildings alike.
The potential for stronger wood could be amazing, even possibly including using wood in order to build armor plating. As part of their research, these scientists found that this fortified wood would be strong enough to deal with bullet-like projectiles. Because while these projectiles would just go through normal wood, they get lodged once the wood has gone through the chemical treatment and heated compression.
Why Make Wood Stronger?
According to the abstract for the article,
Natural wood is a low-cost and abundant material for building and furniture construction. However, the mechanical performance of natural wood (its strength and toughness) is unsatisfactory for many advanced engineering structures and applications.
Scientists are now claiming that thanks to their experimental treatment would make it up to 10 times tougher and 12 times stronger.
Because of this, wood could become a solid competitor (no pun intended) to traditionally tough and strong materials such as titanium alloys, carbon fiber, and steel. What would be the advantage of using wood instead of those materials? The main advantage would be the cost of wood is considerably cheaper than steel or titanium alloys. But there would also be other advantages other than just costs. Another clear example would be the combination of tough and strong, which is rarely found in nature and that wood achieves after it has been put through this treatment.
Another great advantage of this new wood is that while it is a strong as steel it is considerably lighter. Scientists estimate that super wood would be about 6 times lighter than steel, which could make it a lot more practical as a building material with which to work those other tough materials.
The last advantage of using wood in new ways is that you can mold it or bend it into pretty much any shape you need before you begin the process to make it stronger and tougher.
What Is the Process to Make Wood Stronger and Tougher?
The new process to make wood stronger and tougher only has two steps.
- The first step involves boiling wood together with a mix of sodium sulfite and sodium hydroxide. This is a similar process to the one followed when creating pulp out of paper.
- The second step is compressing the boiled wood. This is done by collapsing each of the walls between the individual cells. You would need to add heat to this process so as to encourage chemical bonds to be created as they would gradually compress.
These two steps also do something else for the wood: as the material is going through these two steps it also becomes stripped out of some polymers while keeping others. Getting rid of some polymers allows the wood to reform, while the polymers it keeps are the ones that maintain the wood’s strength. But not only does this process merely maintain the strength of the wood involved, it actually increases it. The way in which this chemical process increases wood’s strength is by the bonding that happens between the wood’s nanofibers of cellulose (which are an essential part of the structure of the wood) and a large number of hydrogen atoms generated as part of the process.
These two seemingly simple steps actually generate a complex series of chemical reactions. And that is just one of the best things about his whole thing: the process of making wood stronger is both simple and not expensive. So, not only is wood a cheaper material than steel but the process of make it just as strong will not add much to the over costs nor would it be complex or time-consuming.
If we add to all of that that trees grow naturally, the advantages increase greatly.
Another great thing about this scientific discovery is that the process has been tried out on many different varieties of wood and it has been shown to work equally well in all of them. So, are we ready to start using super wood in building cars, etc.? Well, maybe not quite as yet. More work needs to be done in order to both scales up the process and speed it up. So, there is still a lot more work that needs to be done before we are able to start using this kind of wood as a reliable building material.
The title of the Nature article is “Process bulk natural wood into a high-performance structural material”, and it is authored by the following researchers: Jianwei Song, Chaoji Chen, Shuze Zhu, Mingwei Zhu, Jiaqi Dai, Upamanyu Ray, Yiju Li, Yudi Kuang, Yongfeng Li, Nelson Quispe, Yonggang Yao, Amy Gong, Ulrich H. Leiste, Hugh A. Bruck, J.Y. Zhu, Azhar Vellore, Heng Li, Marilyn L. Minus, Zheng Jia, Ashlie Martini, Teng Li, and Liangbing Hu. The full article was published online on February 7, 2018.