Corrosion resistance testing assess the impact of corrosive atmospheres on components, coatings, etc. Atmospheres are in general classified in to reductive, neutral, and oxidative atmosphere. Normal air which contains oxygen can be considered oxidative. Thus, some materials like iron will continue to rust and become oxidized if exposed to normal air for long period of time. Reductive atmosphere occurs in equipment like furnaces, internal combustion machines, etc.
Corrosion resistance testing can be classified in to pure corrosion and stress corrosion testing. In pure corrosion testing materials and components are exposed to only corrosive atmosphere to assess the reaction. Typical examples are rusting, hydration, etc. Buildings and structures suffer from simple corrosion attacks. Stress corrosion testing involves mechanical forces in addition to corrosive atmosphere. Power generation equipment like boilers suffer from mechanical forces in addition to corrosion. These mechanical forces are variable, thus leading to a combination of corrosion and fatigue. Often equipment like gas, steam turbines, etc., operate at high temperatures. Corrosion in these cases is augmented by mechanical loading at high temperatures. In extreme cases like nuclear power generators, materials suffer from irradiation from neutrons, and other sub atomic particles in addition to mechanical forces and corrosion. Some known corrosion tests are CASS, NAWLT, EXCO, etc.
Capability – At TTL, we test components and coatings for a variety of customers from aerospace, automotive, truck OEMs as well as mining, metals, and coating manufacturing markets. We have several environmental cabinets to run salt spray, salt fog, acidified salt spray, etc., on small test coupons to full sized components like truck wheels, auto wheels, etc. In addition, we have specialized fixtures for stress corrosion testing of material coupons. We have also environmental cells for testing corrosion fatigue, which is generally carried out in a regular tensile test frame under tension or flexure mode. The cells have capability also to run at higher or lower temperatures if required.
Some relevant standards:
Touchstone is committed to providing its customers with quality, reliable test results. That is why we have undertaken the rigorous steps needed to meet and secure the most stringent of test lab accreditations including ISO/IEC 17025, NADCAP 7101 (Materials Test Lab) and NADCAP 7122-I (Non-Metallics Materials Testing).