The influence of Si on structure of aluminide coatings deposited on TiAl alloy

AbstrAct Purpose: Increasing oxidation resistance of TiAl intermetallic alloy by depositing aluminide coating by slurry method and investigation of the influence of Si addition on structure of obtained coatings Design/methodology/approach: The structure of coatings was investigated by light scanning microscopy. The chemical composition of coatings was investigated by EDS method and XRD phase analysis was used as well Findings: The investigation has showed that the thickness of the coatings ranged from 30 to 40 µm. The structure of the silicon-modified aluminide coatings is as follows:- the outer zone consisting of TiAl 3 phase and titanium silicides- the middle zone consisting of columnar titanium silicides in phase TiAl 3 matrix- the inner zone consisting of TiAl 2 phaseThe analysis of the average chemical composition of the outer zone exhibited the gradual increase of the silicon content along with the increase of this element in the slurry. The phase analysis has confirmed Ti

[1]  D. Wee,et al.  Effects of Al–21Ti–23Cr coatings on oxidation and mechanical properties of TiAl alloy , 2002 .

[2]  W. Quadakkers,et al.  Oxidation-Resistant Aluminide Coatings on γ-TiAl , 2003 .

[3]  Fu-hui Wang,et al.  Effect of MCrAIY overlay coatings on oxidation resistance of TiAl intermetallics , 1998 .

[4]  L. Singheiser,et al.  Development of oxidation resistant coatings for γ-TiAl based alloys , 2002 .

[5]  K. P. Rao,et al.  In situ composite formation in TiAlSi ternary system , 1999 .

[6]  Rui Yang,et al.  Alloy development and shell mould casting of gamma TiAl , 2003 .

[7]  Toshimitsu Tetsui,et al.  Gamma Ti aluminides for non-aerospace applications , 1999 .

[8]  S. Zec,et al.  Microstructure and mechanical properties of precision cast TiAl turbocharger wheel , 2005 .

[9]  KyooYoung Kim,et al.  Effect of Cr addition on the properties of aluminide coating layers formed on TiAl alloys , 2002 .

[10]  S. Gong,et al.  A study on aluminide and Cr-modified aluminide coatings on TiAl alloys by pack cementation method , 2000 .

[11]  Xiaohong Li,et al.  Liquid-phase siliconizing by Al–Si alloys at the surface of a TiAl-based alloy and improvement in oxidation resistance , 2004 .

[12]  Edward A. Loria,et al.  Quo vadis gamma titanium aluminide , 2001 .

[13]  Y. Murakoshi,et al.  Plasma spraying of titanium aluminide coatings: Process parameters and microstructure , 1995 .

[14]  P. K. Datta,et al.  Codeposition of Al and Si to form oxidation-resistant coatings on γ-TiAl by the pack cementation process , 2003 .

[15]  K. Nakagawa,et al.  Influence of siliconizing on the oxidation behavior of a γ-TiAl based alloy , 2003 .

[16]  P. Cheang,et al.  Intermetallic coatings produced by TIG surface melting , 2001 .