Plasma Electrolytic Oxidation PEO

Habibovic et al., 2002 Kokubo, Kim and Kawashita, 2003 Kokubo and Yam-aguchi, 2011), formation of thin calcium phosphate films on functionalised surfaces (for example Bunker et al., 1994 Tanahashi, Yao and Kokubo, 1995 Layrolle, 2011), laser surface engineering (Kurella, 2005), plasma electrolytic oxidation (PEO, Yerokhin et al., 1999 Yerokhin, 2005 Curran and Clyne, 2005 Wang, Fu and Chen, 2012), pulsed laser deposition (PLD) (Wang et al., 1997 Koch et al., 2007 Man et al., 2009) and several other less frequently applied techniques. 

Figure 5.44 (a) Titanium oxide coatings produced by plasma electrolytic oxidation (PEO) on a cp-titanium substrate, (b) Higher magnification (Zhao, Feng and Zhao, 2014). 

An investigation of ceramic coating growth mechanisms in plasma electrolytic oxidation (PEO) processing. Electrochim. Acta, 112, 111-119. 

Plasma-Electrolytic Oxidation (PEO), InTech Publication, pp. 201-239. www. intechopen. com/download/pdf/46222 (accessed 13 October 2014). 

The effect of plasma electrolytic oxidation (PEO) treatment on the SCC of surface-modified magnesium alloys was studied [167]. PEO coating offered improved corrosion resistance. However, the barrier film did not improve the SCC resistance in ASTM D 1384 test solution. The SCC of PEO-coated specimens was attributed to the development of micro cracks in the coating, leading to substrate cracking under SSRT test conditions [167]. 

Physical functionalization by the application of surface coatings, including APS (atmospheric plasma spraying), CVD (chemical vapor deposition), CGDS (cold gas dynamic spraying), PLD (pulsed laser deposition), MAO (micro-arc oxidation) or plasma electrolytic oxidation (PEO), sol-gel, and polyelectrolyte coatings and films. 

Plasma electrolytic oxidation (PEO) is an efficient method for production of functional ceramic surface layers on non-ferrous metals, such as aluminium, magnesium, zirconium and titanium alloys. During PEO process the electrochemical reaction of anodic oxidation on the metal surface is assisted by micro-discharge events to promote formation of thick, hard and well-adhered oxide ceramic surface layers with specific morphologies and phase compositions, exhibiting superior protective performance and other useful electro-physical and chemical properties. ... 

COMA (2008), Keronite Plasma Electrolytic Oxidation (PEO) technology [Online]. Keronite Advanced Surface Technology. Available http //www.keronite.com/ technology centre.asp [Accessed 2008]. 

Surface treatment is a popular method for corrosion prevention. Bala Srinivasaneia/. [154,155] studied plasma electrolytic oxidation (PEG) coated LB welded AZ31 and FSW AZ61. The PEO coating increased the corrosion resistance, but did not improve SCC resistance. The failure to improve SCC resistance may be because the PEO coating is brittle. 

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