HACT

After 1 week’s HACT

In just 1 week, HACT (Highly Accelerated Corrosion Testing) is able to produce corrosion equivalent to that observed after more than 10 years of use in a "normal outdoor environment" without substantial sources of pollution, or 5 years in a maritime environment.

New corrosion test

DELTA has developed a new accelerated corrosion test called HACT, Highly Accelerated Corrosion Testing. The intention of the test is to determine the durability of equipment and materials used in corrosive environments, i.e. ships, wind turbines and cars, early in the development phase.

HACT provides the balance between sufficient acceleration of corrosion and realistic results

It is not immediately possible to find one single test which influences all corrosion mechanisms at the same time. Furthermore, it is very difficult to accelerate corrosion sufficiently, without using pollutants (gases, chemicals etc.) which will give completely unrealistic results. For instance, it is not possible to compare two types of connectors by putting them into concentrated hydrochloric acid, and then find out that one connector has virtually disappeared, whereas the other has not. The connector which disappeared could easily be of a plastic type which does not tolerate hydrochloric acid, but is perfectly usable in the use environment - maybe even better than the other type of connector which passed the hydrochloric acid test. Acceleration of corrosion is therefore only possible to a certain degree, if you want realistic results.

HACT is based on the parameters of reality

Experiences show that it is mainly "ordinary" atmospheric corrosion, and in particular salt spray/mist, which causes problems for the reliability of products intended for outdoor use.

DELTA's new HACT test is based on the following selected parameters, which give realistic results in a short time:

• Increased temperature
• Increased humidity
• Cyclic spraying with cold aerated salt water
• Cyclic drying with high air flow, adding additional oxygen to the corrosion process.

HACT is based on the experiences with HALT

Since 2002, DELTA has carried out thermo-mechanical HALT, Highly Accelerated Life Test, where weaknesses in a product are found by exposing it to combinations of temperature and vibrations exceeding by far the specified levels.

In particular, the HALT philosophy is useful in the development of new test methods to investigate other parameters, which could provoke failures on equipment, i.e. humidity, pressure, voltage variations, electromagnetic exposures etc.

Over the past couple of years, numerous reports from DELTA's clients have shown that in particular corrosion is causing problems in the field. And equipment developers/designers generally demand that problems with humidity are found and solved during the development phase, as effectively as temperature and mechanical problems with the thermo-mechanical HALT.