Microstructure and Corrosion Behavior of Laser Synthesized Cobalt Based Powder on Ti-6Al-4V

International Conference on Nanomaterials and Biomaterials 2017

材料科学;物理学;生物科学

Adesina, O.S.^1 ; Popoola, A.P.I.^1 ; Pityana, S.L.^2 ; Oloruntoba, D.T.^3

Department of Chemical and Metallurgical Engineering, Tshwane University of Technology, P.M.B. X680, Pretoria

0001, South Africa^1

Council for Scientific and Industrial Research - National Laser Centre, P.O. BOX 395, Pretoria 0001

BLD 46F, South Africa^2

Department of Metallurgical and Materials Engineering, Federal University of Technology, P.M.B. 704, Ondo - State, Akure, Akure, Nigeria^3

关键词: Anodic current density;    Corrosion behavior;    Corrosion current densities;    Deepwater energies;    Laser cladding technique;    Metallurgical bonding;    Offshore components;    Processing parameters;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/350/1/012007/pdf
DOI  :  10.1088/1757-899X/350/1/012007

来源: IOP

【 摘 要 】

The corrosion behavior of titanium alloys when used for various dynamic offshore components has been a major concern of titanium drilling risers in deepwater energy extraction. A way of achieving specified requirement is the development of coatings suitable to protect the base material against corrosion. In this work, laser cladding technique which is known as a leading edge due to its distinctive properties and outcomes was used in synthesizing Co-based powder on titanium alloy. The processing parameters used were laser power of 900W; scan speed of 0.6 to 1.2 m/min; powderfeedrate1.0g/min;beamspotsize3mm;gasflowrate1.2L/min.The effects of cobalt addition and laser parameters on corrosion behavior of laser clad Ti6AL4V coating in 0.5M sulfuric medium were investigated using linear potentiodynamic polarization. The changes in microstructure and corrosion behavior were analyzed using scanning electron microscopy (SEM) while the X -ray diffraction (XRD) indicates the intermetallics in the coatings. Results showed that the coatings displayed good metallurgical bonding with dendritic formations between the coatings and the substrate. The anodic current density increased with lower scan speed. However, the corrosion current densities of laser-clad samples were lower than Ti6Al4V alloy.