Benefits of Zinc Coated Sheet Metal
Zinc coated sheet metal offers several key benefits. Whether it is galvanized, electrogalvanized or a zinc-rich paint coating, the zinc provides barrier and cathodic protection for the underlying steel.
Pre-galvanizing is performed at the mill and involves rolling shaped steel stock through a cleaning agent to quickly prime it for galvanization before passing it through molten zinc and immediately recoiling. This allows for faster galvanizing of longer coils of steel and a more uniform coating.
Corrosion Resistance
Zinc plating protects steel from corrosion in two different ways. First, it forms a barrier between the steel and oxygen, so the oxygen cannot react with the steel. Secondly, it acts as an acid-resisting barrier to prevent the steel from being exposed to the elements, which could otherwise cause it to oxidize and corrode.
In addition to providing protection from corrosion, the zinc coating also makes the steel look shiny and new. This is great for presenting a polished, professional image and can give customers a sense zinc coated sheet metal of confidence that the products they purchase are high quality.
For comparison purposes, the values of one-year atmosphere corrosivity parameters (K1) for steel 08ps, ZnAlMg and HDG were determined and compared. The K1 values for samples of all four materials at the three marine sites and at FECS were comparable, although the average values at open area and shelter were significantly different. This may be due to the fact that sea salts are not washed off by rains in shelter conditions.
The galvanization process is a common method of adding a protective coating to steel and other metals. Items are dipped into a bath of molten zinc to create an extra layer that prevents corrosion. The zinc coating can be applied to a variety of steel and metal items, from small screws to large structures. It is a highly versatile and economical method of protecting steel.
High Durability
The sacrificial nature of zinc prevents the corrosion of iron and steel beneath it, which allows galvanized sheet metal to endure in harsh environments. Zinc coatings also provide a barrier that prevents moisture from coming in contact with the metal itself, slowing down the rate at which rust or corrosion begins.
The smooth, silvery appearance of a freshly hot-dipped galvanized surface is dulled down over time to form an attractive patina. The coating can be further enhanced by painting with a clear, dry primer or a zinc based paint. These coatings are durable, withstand high temperatures, and resist chemical attack from acids and alkalis.
A galvanized coating is very ductile and able to bend and conform to the shape of the steel it protects. Galvanized steel is used extensively in automotive manufacturing, where it is the choice for many components of the ‘body-in-white’. It is also a popular choice for hardware products like fasteners, castings and other fabricated items, as well as household appliances and electrical steel products, and even machine casings.
Batch hot-dip galvanizing is a standardized process that produces a quantifiable coating thickness, offering corrosion protection with lifespans that are easy to forecast and depend upon. This type of coating can be readily specified through British, European and international standards. Zinc coatings are also very recyclable, allowing them to be melted and reused instead of discarded after use.
Low Maintenance
Unlike powder coating, zinc plating doesn’t require extensive chemical cleaning to prepare the metal for application. In general, the metal is simply rolled or pushed through molten zinc to receive a thin coating of protection. The coating is then cured in a heated oven, which typically takes less than 10 minutes. This reduces the time the steel is exposed to bare metal and the subsequent corrosion.
In addition, the tightly adhering zinc coating can withstand some of the most severe forming operations without flaking. This helps eliminate expensive die costs while ensuring that the finished product is ready for use. The adherence of the zinc coating also provides excellent lubricity for bending and punching operations and makes it possible to spot weld components with confidence.
Zinc coatings are also far safer than cadmium plating and other forms of zinc coating, which generally contain at least one substance that is harmful to humans. Furthermore, unlike chromium, which is used in the plating of some products, zinc is found in our bodies naturally and has a very low galvanic potential, meaning it acts as a cathode when near corrosive metals.
When it comes to long-term performance, few forms of steel corrosion protection are as cost effective as hot-dip galvanizing. This is especially true when comparing it to the relatively new phenomenon of powder coating, which must be coated over and over again in order to achieve the same protective level.
Economical
The long lifespan of zinc-coated steel products means they do not need frequent replacement, which reduces overall life-cycle costs. Zinc is a very affordable metal, and its low melting point makes it cheap to melt and form into sheet. In addition, it is easily recycled.
Hot-dip galvanizing is the process used to add a metallic zinc coating to steel products. In this process, the product is immersed in a molten zinc bath where it reacts with iron to create a series of zinc-iron inter-metallic alloy layers. These layers protect the steel from oxidation and corrosion. The galvanized steel supplier galvanizing process is also able to protect steel from damage caused by handling, impact or mechanical stresses, such as distortion or warping.
Galvanized products are often referred to as galvanized steel or galvanized plate. This steel is typically sold in sheets, coils or bars. It is used in various industries such as construction, automotive, appliance and electrical hardware.
Using a zinc-coating in metal forming applications is an excellent way to protect the surface from corrosion. Zinc coatings are also a cost-effective choice for products that require moving contact between components such as stampings and injection castings/moldings. The low friction of zinc ensures a smooth surface that can prevent damage and dents to the part. This is especially important when using a thin zinc coating such as powder coat or paint.