• Thermally Sprayed (Metalized) Alloys
• Impressed Current Systems
• Sacrifical Systems
• Corrosion Evaluation and Engineering
• LifeJacket® System

Cathodic protection systems operate by causing a direct current to flow from an external source to the metal structure (the anode) to surfaces of the structure (the cathode). When the current is adequate and properly distributed, corrosion is mitigated and the structure is cathodically protected.

For a cathodic protection system to work, current must be discharged to the electrolyte from an anode. In discharging current, the anode corrodes. Because the sole purpose of the anode is to discharge current, it should be made of materials that corrode slowly or do not corrode at all.

Cathodic protection does not eliminate corrosion; it merely transfers it from the structure being protected to a less expensive, consumable, non-dangerous, known location – specifically, the anode. There are basically two methods of applying cathodic protection, although there are numerous variations of these methods. The basic methods are sacrificial or galvanic and impressed current. CRT specializes in designing and installing thermally sprayed (metalized) cathodic protection systems for reinforced concrete structures.

CRT Metalized Cathodic Protection (MCP) System®:

Metallizing consists of the application of a coat of metal on a properly prepared substrate. This is achieved by melting the metal and propelling it onto the surface to be coated. Metallizing or thermal spraying as it is also known, was first developed in the 1920s, and it is a proven technology for corrosion protection, rebuilding of worn or damaged parts, dimensioning, and fabrication of metal parts and components. CRT's MCP SYSTEM® consists of the application of metalized cathodic protection coatings to reinforced concrete and metallic surfaces.

When used for corrosion protection, metallizing is used to apply a protective coating to the structure surface of concern. The coatings can be sacrificial, such as zinc, aluminum and other alloys or they can be noble or cathodic. Examples of the latter are stainless steels, tin, cooper and copper alloys, bronzes and many others.

When sacrificial coatings are used, in addition to providing a barrier between the structure and the corrosive environment, the coating material will protect the metal at coating deficiencies and exposed areas. Sacrificial coatings are often used in combination with sealers and barrier coatings. These overcoats are used primarily for aesthetic purposes but they also help seal the porosity that is inherent to metallized coatings and provide a degree of protection to the metallized coating from the environment. Metallized coatings provide a highly synergistic relationship with sealers and paints, because the paints are anchored on an excellent substrate and typically last much longer than when applied directly on to the steel. Cathodic coatings are chosen for their resistance to corrosion in a particular environment and they primarily act as barrier coatings. The quality of the application becomes very important when using cathodic coatings, because small defects and coating damage will cause the substrate to corrode faster since it is anodic to the coating.