Thermal Spray Coatings for Corrosion Prevention

—Current Status and Future Perspective—

Abstract

Two types of thermal sprayed coatings for corrosion prevention in natural environments are discussed in this review. One is a sacrificial anode type coating of zinc and aluminum, which has a long history dating back to 1940's and will become more important as the expected service life of infrastructures become longer and the existing structures require good maintenance technology. The other is a dense barrier type coating of materials such as stainless steels and Ni-base alloys, which becomes more applicable due to the recent development of spray processes such as HVOF. Basic corrosion properties and field performances as well as problems to be solved of HVOF sprayed alloy coatings are discussed.