REPUBLIC OF SERBIA

MINISTRY OF DEFENCE

www.mod.gov.rs

MINISTRY OF DEFENCE

Material Resources Sector

Defensive Technologies Department

Military Technical Institute

www.vti.mod.gov.rs

Corrosion characteristics of laser cleaned brass surfaces

Bojana M. Radojković

Institute of Chemistry, Technology and Metallurgy, Belgrade, Serbia, e-mail: bojana52@yahoo.com

Bore V. Jegdić

Institute of Chemistry, Technology and Metallurgy, Belgrade, Serbia, e-mail: borejegdic@yahoo.com

SLAVICA S. RISTIĆ

Central Institute for Conservation in Belgrade, Belgrade, Serbia, e-mail: s1avce@yahoo.com

BILJANA M. BOBIĆ

Institute of Chemistry, Technology and Metallurgy, Belgrade, Serbia, e-mail: biljanabobic@gmail.com

SUZANA R. POLIĆ

Central Institute for Conservation in Belgrade, Belgrade, Serbia, e-mail: suzanapolic64@gmail.com

Abstract: Different types of weapons and military equipment, made of brass, are often exposed to extreme atmospheric conditions, to chemical agents, erosion and wear. It is important to evaluate the corrosion characteristics of brass in different corrosive environments, and especially after laser cleaning of corrosion products, various deposits and other undesirable surface layers. The brass corrosion resistance changes, after surface laser cleaning, were examined in this paper. Nd:YAG laser with λ=1064 nm was used for laser cleaning process. SEM analysis was applied for investigation of the brass surface micro-morphology before and after laser cleaning. Electrochemical techniques such as linear polarization resistance, electrochemical impedance spectroscopy, linear sweep voltammetry and electrochemical frequency modification were used to study the corrosion characteristics of laser treated and mechanically prepared brass surface. The results of electrochemical tests have shown that the corrosion rate of laser treated brass surface is approximately same as the corrosion rate of brass surface prepared by the standard grinding and degreasing process. This indicates that the brass surface was efficiently cleaned by laser treatment with applied operating parameters without lowering its corrosion resistance. The abilities of different electrochemical methods for determination of corrosion rate were compared.

Keywords: laser cleaning, brass, corrosion resistance, electrochemical methods.