Not many people are aware of the importance of materials for our technological advancement. Whenever ancient civilizations made an advancement it was due to metallurgy. As our focal topic is Is Machining Vespel Easier Than Machining Metal?
This can be seen clearly by the way we categorize ancient times. They are categorized by the ability to refine and use certain materials such as copper, bronze, and iron. It may seem a bit weird from today’s perspective, but at that time these materials were revolutionary and all due to chemistry.
We have faced a new revolution quite recently with new material, plastic. We are currently living in the age of plastic and that is the reason why we are so advanced currently. Everything around us is partly made out of plastic held by different glues, which are also polymeric materials. We can see how a plastic material, such as Vespel, compares to metal in the example of machining.
What is Vespel?
Vespel is the trademarked name given to a polyimide-based plastic. Plastic is a very broad term but it can be defined in simple terms. Plastic is made out of an organic molecule that reacts with neighboring molecules to make a very large thread made out of the same starting molecule.
These threads interact with other polymerized threads through weak interactions. The interactions by themselves are weak, but when there are so many of them, they become much stronger. For example, breaking one stick is easy, but breaking several sticks at the same time is not.
There are many types of plastic and thus many other types of Vespel. Each type has its own unique properties depending on its molecular structure. Predicting these properties only through chemistry can be hard, so experimental data is essential to know the exact properties. Different types of this polymer are vespel sp1, Vespel sp3, Vespel sp21, and so forth. Some of the properties that are most often compared are heat resistance and chemical reactivity with other reagents.
Properties of metal
Metallic materials are made out of highly ordered atoms or ions of the metal species. They are crystals and their stability also depends on the way these atoms are arranged in space. Besides that, they are mainly stabilized by ionic forces and in rarer cases, covalent bonds. Covalent bonds are much stronger, an example of that is diamond, but these materials are harder to find.
Most of the metallic materials are alloys or mixtures of different salts that can crystalize together. Making these materials is cheaper than making high-quality and high-performance plastic such as Vespel. Not only that but many of the industries are used to using metals. Switching to Vespel can be tough and it is an investment, but one that you should definitely consider.
Ease of cutting/machining
When you compare interactions that hold Vespel together and the ones that hold the most common metals, you can see that interactions in Vespel are much tougher. The crosslinked threads are held by covalent bonds in addition to many other weak noncovalent bonds. That means that Vespel is going to be tougher than most metals. If the material is tougher, that means that it is also going to be harder to cut it.
It is not easy to do it and you will need another type of equipment to do so. Tungsten cutters can do the job, along of course diamond cutters. They are stronger than Vespel so they can get through it and cut it the way you want to. The other downside is that many people are not skilled in machining Vespel because they did not have the chance to do it before. That means that you or your workers will need to learn and train how to do it properly before you can start using it more often.
Does that mean it is not worth it?
The short answer is no. Even though it is an investment to switch to Vespel, not only because of the material but because of the equipment, it does not mean that you should not consider it. The reason why it is so hard to cut it is actually a huge benefit. It is much more durable and there are other types of Vespel that can give you other advantages.
Besides that, during machining, Vespel will not bend. The main problem with metals is that under the circumstances of machining they can bend and ruin the material. Not only that, but many metals are prone to be overheated. The friction from cutting heats up the metal and thus can cause damage.
The dangers of heat that are not talked about
Heating is not only bad for the material but also for the cutter. The more heat it takes the more it gets worn down. Not only that but for metals the outcome can be surprising. When heated up, metals become more reactive. Even if you do not see the reaction, it is going on with oxygen in the air. Unwanted oxidation is a problem that can occur if you do not handle metal correctly. Heating is less of a problem if you use a material that is more smooth because the surface has fewer edges that cause friction. Even if heating does happen, it is also not a problem if the material is chemically inert to many reagents.
Even though it is harder to machine Vespel compared to metal, that does not mean that this material does not have a future. This material has proven quite useful for the aerospace industry. Because it is so durable and less prone to heating and oxidation, it is an ideal material for planes and rockets. This industry is the future and Vespel does have the means to have a role in that future.
Last about Is Machining Vespel Easier Than Machining Metal? Making new plastics with these kinds of properties is what we should be focusing on. There are many other parameters that should be compared when thinking about the upsides and downsides of Vespel.
This is just one of these, let’s not forget about the process of manufacturing, health aspects, the potential for a greener future, and many others. Just as it was mentioned earlier, the biggest technological jumps come from new materials and this is just one example that we are living through right now.