Despite the development of some new and inventive building and construction materials, metal is still a vital component in the majority of projects around the world. Prized for its strength and durability, metals such as steel are commonly used in both small and large construction projects. From towering skyscrapers to schools and businesses, steel plays a key role in the structural integrity of buildings.
While metals have many benefits and advantages on their own, there are two key metal treatment processes that are important to understand because of the impact they have on metals.
The importance of metal pre-treatment can be seen when we look at one of the most effective ways of painting metals, powder coating. Unlike other painting techniques, powder coating does not use liquid paint. As suggested by the name, a paint powder is used to cover the metal. The powder is applied using an electrostatic gun with compressed air. Powder coating is effective as the powder can stick to the metal surface not only because of the pressure applied from the compressed air but also the difference in charge between the powder and the metal. The target piece of metal is earthed, and the powder receives a negative charge thanks to an electrode in the electrostatic paint gun.
A crucial part of the powder coating, which gives the powder the best possible surface to stick to is the pre-treatment process. Depending on the metal that is being coated, there are different pre-treatment methods. However, the main aim is always the same – to remove any surface dirt or rust, which could reduce the effectiveness and ability to powder coat the metal. This is vital for industries that rely on the metal being a visible part of a project. In certain construction projects or even in the car and motorcycle industry where metals are powder coated for aesthetic and functional reasons.
Two of the more popular forms of metal pre-treatment cleaning methods are shot blasting and aqua blasting (sometimes known as vapour blasting or wet blasting). Shot blasting is an aggressive cleaning option that is perfect for removing surface defects but less effective at removing finer contaminants such as oils. Aqua blasting is a less aggressive pre-treatment process, which uses micron glass particulates in a high-pressure water jet to clean the metal.
It should be said that when painting or coating any metal, it is always advisable to clean it first to achieve the best possible result. This includes projects which you may not think of, such as boats that need marine coatings or even just painting garden furniture at home.
Another important pre-treatment process is the phosphate coating. This is where components are either dipped in or hot-sprayed with a variety of phosphate coatings, including manganese, zinc, and iron. The benefits include providing a long-lasting crystalline coating, improved lubrication, and improving paint and powder adhesion. For industries where they need parts to move together, this can be crucial. The automotive and engineering industry can really benefit from using phosphate coatings.
2. Heat treatment
A variety of industries can benefit from heat-treated metal. This is because there are so many different alterations to metal properties that come from heat treating the mental. For example, tempering is a process where a metal is brought up to a specific temperature after being hardened, kept at that specific temperature, and then quenched. The result increases the toughness of the metal, which can be beneficial in the construction industry where the metal may need to be exposed to the elements.
Steel is a good example of the benefits which can come from heat treatment. Not only can it become more durable but also easier to weld and its wear-resistance and overall lifetime increases. The basic idea of heat treating is to control the size of the metal grain structure precisely. The smaller the grain structure, the better the mechanical properties of the metal are.
Overall these metal treatment processes are important to a variety of industries. They allow the metal to perform at its best and can positively impact the lifespan of the project. This is not only beneficial to the customer but also to those responsible for the project.