We start the test procedure within 24 hours. Coating conditioning, thickness measurement, adhesion tests are regular starters. Our laboratory is a 100% climate controlled.

Various corrosion test standards permit different starting days, normally we put the material in cabinets Mondays and Fridays. Contact service@coteclabs.com for more information.

It depends on the test standard. An ACT test is usually 6 weeks and an NSS test could vary from 6 up to 1400 h. We can start the test-procedure within 24 h and deliver an accredited report from 24 hours after finished test.

We always define a delivery time and dedicate a contact person when sending the order confirmation. We are flexible though, assisting with faster report deliveries upon customer’s request. We are proud that we have the fastest lead times on the market.

No, we get test materials from all over the world. The shipping time is normally 1 to 3 days.

Don´t worry. Please contact us and we can help you. We have over 300 standards available and years of experience. We can also develop or put together a test that suits your needs and requirements.

We are an accredited laboratory with great experience in corrosion and coating/paint integrity tests. We believe in real quality, we focus on having the right equipment, order, routines and most important – competent, flexible and accurate employees. And of course, we have the fastest lead times on the market. We are also able to guide our customers to tests according to the best test standards and to help our customers with failure analysis.

In the evolution of materials science, cyclic corrosion testing represents a significant part in evaluating the corrosion resistance of materials and coatings. Unlike conventional steady-state exposure tests, many cyclic methods offer a more realistic methodology by simulating real-world environmental conditions through accelerated corrosion tests.

When exposing test samples to varying conditions, cyclic corrosion testing better represents the complex corrosive processes materials face in field of use. What it significantly means is that cyclic corrosion testing involves exposing samples to alternating wetting and drying, often incorporating salt spray or salty acidified rain with a humidity setting relative to the fluctuating temperature. This approach really shows the limitation of conventional salt spray tests where a steady state of humidity, fixed temperature or both is the case. The conventional methods then fail to account for the natural alternate between different environmental states. 

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Why cyclic corrosion testing
Author: Joakim Ekström, Corrosion test expert, Cotec Labs

The yearly loss of 3-4% of GNP in favour of corrosion decay has been a fact oven the last couple of years. Corrosion can cause damage to any product, reduce its lifespan, and affect its performance, which can lead to safety hazards or financial losses. By adequately testing the coating, manufacturers can evaluate its resistance to corrosion and make improvements where necessary.

There are several types of corrosion tests that can be conducted on coated products, for example salt spray, humidity, immersion, and cyclic corrosion tests. These different tests simulate harsh environmental conditions the product probably will be exposed to during average use, such as saltwater, moisture, or chemicals. By exposing the coated product to these conditions for a specified duration, one can determine the coating’s effectiveness in preventing corrosion, and decide whether the product needs additional coating or protection.

In summary, exposing coated real products to corrosion during test is important when assessing the durability and effectiveness of the coating. It helps ensure that the product will last longer, perform well, and will reduce safety risks or financial loss caused by corrosion. And let´s not forget about the sustainability aspect.

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Corrosion test of aluminium components
Auther: Stefan Gustafsson Ledell, CEO, Cotec Labs

What test method should I choose?

The most important thing is to be honest with yourself when it comes to selecting a test method. There are methods ranging from simple to advanced, from inexpensive to costly, and some methods are more common than others. Always consider the purpose of the testing and the quality/requirements that the product needs to withstand or be exposed to. Ask yourself: How can I test my product in the best way to simulate real conditions? Is 5% salt mist and a temperature of 35°C the climate my product will be exposed to? Or does the product sometimes get wet, dry, hot, or cold? What humidity levels will it face? Is the climate constant or variable? Does the product depend on seasons?

For example, a product used in dry conditions during the day may corrode due to condensation that accumulates at night. This demonstrates that cyclic testing methods are often more realistic than constant tests when ensuring product quality against specific requirements. Constant tests are better suited for process verification, where different process parameters are compared.

Different test methods for aluminium

There are many test methods used in the industry to assess products’ sensitivity to corrosion. These include national standards (SS, ASTM), international standards (ISO), and company-specific methods (Scania, Volvo, Ford).

Regarding atmospheric corrosion, there are generally two types of test methods: constant methods and cyclic methods. The most widespread tests globally are constant methods, especially various types of salt spray tests. They usually have shorter testing times and require simpler equipment. Cyclic tests are primarily designed to simulate real-world conditions. These tests typically have longer durations and demand more from testing laboratories.

• Constant tests: The most common method is called Neutral Salt Spray (NSS) testing. It exists as an ISO standard (ISO 9227) or a variant of it, ASTM B117, which is an American standard. Typically, these standards use pure salt mist, but for more aggressive testing, there are variants with acetic acid (AASS) and copper (CASS). Constant methods also include constant humidity, such as ISO 6270-1/2. The advantages of constant methods are their simplicity, shorter testing times, and ease of identifying weak points. However, repeatability is not optimal, and predicting results based on real-world conditions is challenging. These methods are mainly used for comparing processes or parameters. Constant methods are not ideal for aluminium products, even though many specifications still use them. The reason is that it’s difficult to observe the effects of testing due to the low pH value, which complicates the corrosion process.
• Cyclic methods: Most cyclic corrosion tests were developed for and by the automotive industry. However, they can be applied to many other sectors. In fact, other industries often want to use automotive standards because they are verified against reality. Examples of methods developed by vehicle manufacturers include VW1210, Volvo 423-0014, Scania STD4319, and Ford L476. These tests subject the sample to alternating wet and dry conditions, salt exposure, and sometimes acidification. The advantage of cyclic methods is their verification against real-world conditions, but the downside is that many methods require special chambers. Most manufacturers claim they can perform most cyclic methods, but this is a “truth with modifications.” Ensuring consistent testing parameters across the entire test surface varies among chamber manufacturers.

For painted aluminium, the commonly used method is called ACTII. It serves as a vehicle standard for companies such as Scania (STD4445), Volvo Cars (VCS 1027, 1449), and Ford (L-467), but it is also used in heavy-duty vehicle industries. What sets ACTII apart from other test methods is that it includes more wet periods and longer drying times, which have been clearly verified in field trials. A variant of the ACT cycle is VDA 233-102 (also known as new VDA), a German standard used by several vehicle manufacturers. It also includes a freezing step and has proven suitable for aluminium products. Anodized aluminium that is not painted or coated with other materials is also tested using the ACTII or nVDA cycle. There are other methods to measure the corrosion resistance of anodized products, such as measuring the density of the surface layer, which can be done through thickness measurement or electrical conductivity.

Why choose cyclic corrosion testing?

Cyclic corrosion testing (CCT) is an accelerated test method that exposes components to cycles of salt spray, humidity, temperature, or other environmental conditions. There are several advantages to using a cyclic test method:

1. Real-world simulation: These methods have been extensively compared to real-world tests, making them better at simulating natural environmental conditions.
2. Timesaving: Cyclic methods can accelerate the testing process compared to on-site or SCAB (in-field) tests. On-site tests are time-consuming, and using a more verified test method can reduce the number of tests needed.
3. Cost-effective: By accelerating the corrosion process, cyclic corrosion testing quickly highlights any weaknesses in materials or coatings, reducing the need for costly redesigns or, worse, field failures.
4. Standardization: Cyclic corrosion testing is often performed according to industry standards, providing a standardized test method for comparing the performance of different materials and coatings.

There is a technical report issued by SIS (Swedish Standards Institute) called SIS-ISO/TR 16335:2013, which describes the methods best suited for various environments, materials, and coatings.

Should I test plates or real products?

There are pros and cons to testing plates compared to real products. It’s essential to consider that tested plates often yield better results than what is achievable in reality. However, plate testing is a good method for verifying processes or comparing different processes or coatings. Testing a real product can often reveal the weakest points, such as edges or cavities. A good strategy might be to start with plate testing to fine-tune your process and then verify the product.

In conclusion, actively choose a test method based on the requirements for your product. Continuously test to establish a stable, high-quality process. Consider a cyclic test method tailored to the material, requirements, and surface coatings, such as ACTII or nVDA for aluminium.

Picture 1: ACT2 cycle (for aluminium)
Picture 2: Recommended test-mehods
Picture 3: Recommended test-mehods

A UV test typically refers to a test that measures the effects of ultraviolet (UV) radiation on materials, products, or biological samples. These tests, known as UV exposure testing, are commonly used in various fields, such as material testing. This means evaluating how materials like plastics, paints, and coatings withstand UV exposure, which can lead to degradation, discoloration, or loss of mechanical properties.

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