Plastic versus metal is an age-old debate that we’re sure your workplace is bound to have discussed over the years – both materials are great and have fantastic individual uses, but which material is better?
When comparing the strength of two very different materials such as plastic and metal, we compare them using a strength to weight ratio. This means that their strength is determined by their mass, the use of the material and the resistance.
Historically, metal was always seen as the superior material when it comes to strength and this is for good reason – metal is an incredibly strong material. However, recently plastic has been gaining recognition in this category especially since the introduction of fibreglass. Plastic is a much lighter material and can be extremely strong for the intended use. Comparing pound to pound, fibreglass is stronger than a sheet metal or steel.
An important factor when deciding on the materials you want to use is the lead time these materials have so that you can meet the set deadlines of your project. Bearing this in mind, the process of producing these materials can greatly affect the lead time for your products.
Comparing the process for plastic thermoforming and metal fabrication process, plastic thermoforming can save a lot of production time as well as labour, energy and costs for the process. There are less steps in this process compared to metal fabrication, so this can shorten your lead time and be a better option for projects with a deadline.
When designing a product, the material you decide to use can give you certain limitations when designing. When designing complex products with the need for intricate or geometric shapes you need a material that will give this freedom and allow your designs to come to life.
Although metal is a great material to use for lots of products and designs when you need more design freedom for a product, plastics are a much better option. It is much easier to create complex shapes using plastics because of the use of injection moulds. Plastic also allows you to factor in structural reinforcements to your design also made out of plastic such as ribs or gussets.
There are a lot of opinions surrounding this topic and which is actually better, there are so many factors that go into this so you may just want to make your own mind up once you know the facts. Shipping materials can cause a lot of emissions and fumes to be released into the environment and as plastics are much lighter than metal, this means it costs less to ship plastics as well as releasing less energy compared to the same weight of metals being transported.
However, a large issue with plastics is that they do not degrade by themselves, granted you can get some types of plastics that are bio degradable but not all. However, metal can almost always be recycled and is more commonly recycled than plastics (although this again is on the rise) making this slightly better for the environment.
The process of making both of these materials are equally bad for the environment in most respects. The process of making a metal entails mining into ores in the earth, this creates lots of fumes and uses a lot of energy in the process. Similarly, plastics are created using petroleum which creates similar effects.
When recycled, the negatives for both these materials is offset significantly.
In conclusion, metals have had a longer time at the top but are being overtaken by plastics in terms of efficiency and intelligent design. However, the best material for you will completely depend on your project and what you need from the material you choose.