#zincelectroplating

Appearance is nearly always a factor when you are choosing electroplating. However,  resistance and protection against corrosion are also key factors. In fact, sometimes corrosion resistance is the prime requirement. This is where zinc passivation comes in.

Zinc metal coatings

Zinc metal coatings are highly resistant to corrosion by the atmosphere and most natural waters. This is providing they are not acidic or highly alkaline. They are resistant due to a compact layer, mainly of oxide and hydroxide, which soon forms on a zinc surface. If you carefully rinse and dry the layer after plating, you can preserve the protectiveness of the layer. However, a better way to protect the layer is by applying a chromate passivation treatment. This treatment provides an effective safeguard against 'white rusting' in very damp conditions.  

Types of zinc passivation

There are several types of zinc passivation treatment that can be specified. All of them have different appearances and levels of corrosion resistance. Below, we have listed the treatments recognized in international standards. The times given in brackets are, those to the initial formation of white rust in a neutral salt spray test, such as that described in BS 5466: Part 1: Clear - prevents staining on handling, while preserving bright appearance (10 hours). Passivate and Sealant - slightly iridescent or dull (240 hours). Yellow- yellow or iridescent (72 hours). Olive drab -less attractive opaque brown/green (96 hours), much used by the MOD. Black Passivation – 48 hours Chromated zinc is sometimes used as an undercoat for paint. Electroplating is generally the best way of applying coatings of zinc up to 25μms thick. Although zinc is highly resistant to atmospheric corrosion, it suffers more rapid attack in heavily contaminated industrial areas. This is because of the acidity of condensate that forms under these conditions. Salt present in marine environments also increases the rate of attack, but not to the same extent. The service life of a zinc coating is very much a function of its thickness, as it eventually corrodes away.  

Zinc nickel plating

Zinc provides sacrificial protection to a substrate such as iron or steel when the coating is incomplete or is damaged during assembly or service. This protection is vital in some circumstances. Under moist conditions, however, unless the gap is plugged with corrosion product, exposing the basis metal will locally accelerate dissolution of the zinc. An increasing area of basis metal will be exposed. Inevitably, at some point in time, the protective action of the zinc will cease to extend as far as the middle of this bare area, and the substrate itself will be subject to corrosion. We alloy nickel into the zinc (at about 10 - 15%) which achieves much greater levels of corrosion resistance. It creates a coating with over 10 times the performance of pure zinc.

Zinc plating services

Here at EC Williams, we are proud to be able to offer a wide range of electroplating services to meet as many different customer requirements as possible.  Quality and consistency is at the forefront of our business and the services we offer. We strive to continue delivering the best possible service we can to our clients, each and every time.  With our state-of-the-art facilities, combined with the skills and knowledge of our expert technicians, we can provide businesses and customers with an electroplating service that will not let you down. 

Zinc Plating 

One of the main services we offer here at EC Williams is zinc plating. Using our facilities we can complete the barrel plating of these precision components that are used in a wide range of industries – most commonly the automotive industry.  Zinc plating is a popular process to choose as it provides excellent corrosion resistance to components. At the same time, it offers a good base for any finishing techniques, such as paint or powder.  Our zinc plate and passivate services are often used on components such as pressings, fasteners and turned parts. 

Zinc Plate Passivate Services at EC Williams 

At EC Williams we offer a range of passivates for our zinc plating. These meet the requirements of many industries including automotive, electrical and defence.  We can meet the traditional zinc plating yellow passivation standards (hexavalent) as well as black and olive drab green passivation. To comply with the current environmental legislation (WEEE, ELV and RoHS) we offer trivalent clear. And, we even offer TRIVALENT YELLOW passivation too.  The introduction of trivalent yellow passivation formula was in response to demand from automotive and electrical customers. They need a colour identifier whilst still meeting the environmental regulations. This new yellow passivate achieves in excess of 120 hour salt spray performance before the zinc plating starts to corrode. 

EC Williams – Trust the Experts

Here at EC Williams, there is plenty of choice with our comprehensive range of post plating treatments. Alongside the post-treatments, we can also provide topcoats and other finishes to help enhance your products and give them the protection that they deserve.  Our departments can cater to both small and large scale batches of products, whilst offering a speedy turnaround, all at extremely competitive prices. 

Call us today!

Electroplating specialists, EC Williams are proud to offer zinc electroplating services. You've possibly wondered what zinc electroplating is, and how zinc electroplating works. As leading experts in electroplating, we can answer all of these questions and more. We are a team that go the extra mile when it comes to providing you with a solution. We'll talk you through everything you need to know, to ensure you know exactly what service you'll be investing in.

Zinc Electroplating Services - How Does it Work?