Microstructure and electrochemical behavior of laser treated FeCr and FeCrSiN surface alloyed layers on carbon steel

✍ Scribed by Chong-Cheng Huang; Wen-Ta Tsai; Ju-Tung Lee

• Publisher: Elsevier Science
• Year: 1995
• Tongue: English
• Weight: 585 KB
• Volume: 190
• Category: Article
• ISSN: 0921-5093
• DOI: 10.1016/0921-5093(94)09593-l

✦ Synopsis

Laser surface alloyed Fe-Cr and Fe-Cr-Si-N layers on carbon steel were produced by laser irradiation involving preplaced Fe/Cr and Fe/Cr/Si3N ~ powders, respectively. The effects of Cr content (13-25 wt.%) and microstructure on the corrosion behavior of the laser treated Fe-Cr and Fe-Cr-Si-N alloys in deaerated neutral 3.5 wt.% NaC1 solution were studied. Potentiodynamic polarization tests and electrochemical impedance spectroscopy measurements were used to evaluate the corrosion resistance of the surface layers. The results showed that the Fe-Cr-Si-N treated layer with a fine duplex phase microstructure had a higher pitting potential than the Fe-Cr treated layers. The passive film resistances increased and the passive current density decreased with increasing Cr content in the Fe-Cr layer.