Corrosion resistant coatings are engineered to protect industrial metals from early failure, due to corrosion induced degradation. In the previous post, we discussed various types of corrosion affecting metallic structural components. This post concentrates on different types of corrosion resistant coatings.
Different Types of Chemical Corrosion Protection Coatings
The following are some popular types of chemical corrosion protection coatings used across various industries:
- Halar® ECTFE: This is a melt-processable coating, which offers excellent barrier strength. Halar® ECTFE resists chlorine, aqueous caustics, corrosive chemicals, as well as organic solvents. The coating offers excellent dielectric strength, and can be used in ultra-pure water and chemical applications.
- PTFE: These coatings are well-known for their non-stick properties. However, PTFE coatings also offer excellent corrosion protection. Many manufacturers have developed their own PTFE coatings, which are engineered to provide corrosion protection and lubrication in specific environments.
- Kynar® PVDF: This thick film anti-corrosive coating is extremely durable. It is recommended for applications that are regularly exposed to strong acids, alkalis, and halogens. However, it is not recommended for solvent resistant applications.
- Teflon: Teflon coating is a fluropolymer coating, which is well-known for its non-sticking properties. This coating offers excellent lubrication, and provides a strong anti-corrosion protection. There are variants of this coating:
- Teflon PFA
- Teflon PTFE
- Teflon Multicoat Blend
- Teflon FEP
- Molybdenum Disulfide (MoS2): Typically offered as a dry film lubricant, these coatings have a vast operating range. MoS2 works in an ambient temperature range from -185 to 350 °C, and vacuum temperature range from -185 to 1100°C. These coatings are non-toxic, which makes them a popular choice for various sensitive applications.
- Xylan®: This coating is different from other fluoropolymer coatings, because it is made from composites. It is well-known for its non-stick properties, as well as offers excellent corrosion resistance. These coatings offer excellent wear resistance at extreme pressure. It offers excellent protection from harsh chemicals in extreme temperatures. Xylan® coatings can be used over most metals, ceramics, plastics, etc.
- Epoxy: This corrosion resistant coating is used in applications that are exposed to harsh environments. Epoxy coatings are favored by many industrial applications due to their affordable pricing, and excellent wear resistance. One of the major advantages of these coatings is that they can offer excellent corrosion protection at extremely high temperatures such as + 500 °F. Most times, these coatings are used as primer to improve corrosion resistance of top coatings.
- WS2 – Process SL39 TM: This coating was originally developed for NASA. The coating helps reduce expensive maintenance related problems caused due to corrosion causing fretting, friction, and galling. The coating can withstand loads up to 100,000 PSI, and has operating temperature range from -460°F to 1200°F (-273°C to 650°C).
The choice of the appropriate coating will depend on your application requirements. Here at Microsurface Corporation, we specialize in tungsten disulfide (WS2 per Process SL-39) and molybdenum disulfide based dry film lubricant coatings. Please contact us with your application requirements to see if we can be of assistance.