Steel is one of the most vital materials in modern day construction.
The alloy raw metal made from two key base components – carbon and iron – is used across a huge range of applications around the world. There are a number of functional and aesthetic advantages which makes steel the preferred construction material over many other metals.
There are also many ways in which this already dependable alloy metal can be manipulated to be improved further.
For a long time zinc coating either by hot dipping – galvanising, or electrically bonding – electroplating has been used to protect the steel from corrosion.
For example, But now in construction and architectural design industries as well as premium pipework, they use an insurmountable ever-increasing amount of stainless steel pipe Australia wide.
In this blog, we are going to outline the difference between two of these different adaptions manipulations: galvanised and stainless steel.
What makes galvanised steel unique is a thin protective layer of zinc that is applied. This sacrificially protects the steel from oxygen and moisture which ultimately causes rust. Even with a minor scratch through the coating, the surrounding coating will corrode in preference to the steel.
Making steel more rust resistant ultimately improves the overall sturdiness and aesthetic of the steel – making it much safer to use, easier to maintain, and more pleasant to look at.
The process of galvanization simply means adding a zinc coating. The process can be done a few different ways and is relatively simple, which also makes it cheaper. Hot-dipped galvanisation gives a thick, strong coating of molten zinc and is an incredibly simple process as you could imagine. Whereas thermal diffusion galvanising is preferred when working with smaller, more intricately designed pieces of steel. Zinc electroplating is preferred for smaller components as the micron thin coating does not affect the dimensions of the parts like hot-dip galvanising.
While galvanisation does help protect the steel from rust, it is important to note that the zinc coating does wear away eventually – especially in environments that are highly acidic or close to salt water.
Stainless Steel is made from iron and carbon, with the addition of chromium, and sometimes other elements that offer tremendous corrosion, rust and temperature resistance. The two most utilised are Nickel and molybdenum in varying proportions.
Stainless steel is also easily fabricated, strong, easy to clean, and is visually very appealing. The main difference between stainless and galvanised is that where galvanised simply coats the steel in a protective layer – stainless steel has integral defence against corrosion and rust built into it by the microscopic passive film of chromium oxide on the surface that self heals as the surface oxide layer reconstitutes.
There are more than 100 different grades of stainless steel that are rated on the levels of chromium and other elements added and the application in which they are used. They can be more easily defined into 5 categories:
This is the most commonly used type of stainless steel. It has excellent corrosion and heat resistance with applications made over a wide range of temperatures. It is commonly used in housewares, piping, construction, and architectural facades.
This has similar features to common steel, but with better resistance to corrosion, cracking, and heat. It is commonly used in washing machines, boilers and indoor architecture.
A very hard and strong stainless steel, though it is not as resistant to corrosion as austenitic or ferritic grades. It contains approximately 13% chromium and is used to make knives and turbine blades.
This steel is a composite of austenitic and ferritic steels, making it both strong and flexible.
Duplex is used in a range of industries including paper, petrochemicals and shipbuilding.
These steels are made to be extremely strong with the addition of elements such as aluminium, copper or niobium.
Overall, galvanised steel is less expensive than stainless steel. It is also easier to manipulate, but will never be as reliable and desirable as stainless steel.
If you’d like to know more about stainless steel piping, Visit our website or contact our team today at (03) 9765 5600. Our team of passionate professionals will go above and beyond to ensure that your next build is done right with the right materials.