For a large part of human history, people made things according to what they could find. Some stones can be used as arrows. Others make sparks. Trees can be turned into wood. But the real power is that you can make these same materials into things with different properties. For example, plant fibers become cloth, or rocks give up the metal inside. One of the oldest engineering materials is glass. You might think that although glass is ancient (dating back to at least 4500 years ago), we now know all about it. According to an interesting post by joncartwright in the physical world, we don’t know. Not far.
According to Jon, there are at least five “glass mysteries” that we still don’t understand. Of course, it’s easy to melt sand, soda and lime, which we discussed before, but in fact, many materials turn glassy when they quickly cool from liquid to solid. The problem is, we really don’t understand why.
It is also interesting that almost anything can be made into glass. Do you know that ant colony and crowd behave like glass in Music Festival? Simulated annealing, a computer algorithm for solving difficult optimization problems, is also taking advantage of the same behavior we see in glass.
It is difficult to turn metal into glass. You have to cool it quickly, sometimes billions of degrees per second. But the rewards are huge. Due to the absence of grain boundaries, metallic glasses are not easy to wear and absorb kinetic energy. For example, when a ball bearing strikes a steel plate, it will bounce back several times, but the steel plate will quickly absorb the energy in the bearing. However, the metallic glass plate absorbs much less energy from the bearing. Want to see it? Watch the video below.
We have discussed how glass is made with other old engineering materials. If you have a laser cutter, you can even print 3D glass without using crazy temperatures (the link on that article is dead, but the video still exists).