Influence of heat treatment on microstructure of slurry aluminide coatings type TiAlSi obtained on TiAlCrNb alloy

• Autorzy: Moskal G. , Witala B. , Rozmysłowska A.
• Języki publikacji: EN

Abstrakty

EN

Purpose: Influence of heat treatment on microstructural changes in slurry TiAlSi coating deposited with 12.5% Si concentration on Ti48Al2Cr2Nb intermetallic alloy and investigation of the influence of Si addition on the structure of obtained coatings is a purpose of this paper. Design/methodology/approach: The research allowed identifying microstructural changes that took place during annealing at 950°C of the TiAlSi coating for 2 to 10h exposure in air. A scope of the research encompassed a microstructural analysis with the use of macro and micro investigation - LM, SEM microscopy, XRD phase analysis and EDS analysis. Findings: The investigation has shown that the thickness of the TiAlSi coatings in initial conditions and after a test was in a range from 30 to 40 ěm. The structure of the silicon-modified aluminide coatings is as following: the outer zone consisting of the TiAl3 phase and titanium silicides / the middle zone consisting of columnar titanium silicides in phase TiAl3 matrix / the inner zone consisting of TiAl2 phase. Basic changes were related to differences in thickness in sublayers. Research limitations/implications: The discussed research proves that main reason of much better protection of TiAlSi coated base alloy is related to high microstructure stability of Si modified in TiAl3 phases. In addition silicon decreases activity of titanium, and in consequence the susceptibility of Al to selective oxidation is much stronger. The presence of Si due to Ti-Si phase generation with high oxidation resistance is presented. Practical implications: The slurry method can be applied in aerospace and automotive industry as low-cost technology in production of aluminide coatings on intermetallics. Originality/value: New method of aluminide coatings deposition on TiAl alloys.

Słowa kluczowe

EN

thin coating; thick coating; aluminides; microstructural stability

PL

cienka powłoka; gruba powłoka; glinki; stabilność mikrostrukturalna

• Wydawca: International OCSCO World Press
• Czasopismo: Journal of Achievements in Materials and Manufacturing Engineering
• Rocznik: 2009
• Tom: Vol. 33, nr 2
• Strony: 204--210
• Opis fizyczny: Bibliogr. 15 poz., rys., tabl.

Twórcy

autor

Moskal G.

autor

Witala B.

autor

Rozmysłowska A.

• Department of Materials Science, Silesian University of Technology, ul. Krasińskiego 8, 40-019 Katowice, Poland,

Bibliografia

• [1] H. Clemens, H. Kestler, Processing and Applications of Intermetallic γ-TiAl-Based Alloy, Advanced Engineering Materials 2/9 (2000) 551-570.
• [2] M. T. Jovanovic, B. Dimcic, I. Bobic, S. Zec, V. Maksimovic, Microstructure and mechanical properties of precision cast TiAl turbocharger wheel, Journal of Materials Processing Technology 167/1 (2005) 14-21.
• [3] J. L. Smialek, J. A. Nesbitt, W. J. Brindley, M. P. Brady, J. Doychak, Service limitations for oxidation resistance intermetallic compounds, High Temperature Ordered Intermetallic Alloys VI, Proceedings of the MRS Symposium, vol. 364, 1273-1284.
• [4] L. Swadźba, A. Maciejny, B. Mendala, G. Moskal, G. Jarczyk, Structure and Resistance to Cyclic Oxidation of Al-Si Diffusion Coatings Deposited by Arc-PVD on TiAlCrNb Alloy, Surface and Coatings Technology 165 (2003) 273-280.
• [5] L. Swadźba, M. Hetmańczyk, B. Mendala, G. Moskal, G. Jarczyk, Long-time Cyclic Oxidation of Al-Si Diffusion Coating Deposited by Arc-PVD on TiAlCrNb Alloy, Surface and Coatings Technology 184 (2004) 93-101.
• [6] G. Moskal, M. Goral, L. Swadźba, B. Mendala, G. Jarczyk, Characterization of TiAlSi coating deposited by Arc-PVD method on TiAlCrNb intermetallic base alloy, Defect and Diffusion Forum 237-240 (2005) 1153-1156.
• [7] J. W. Fergus, Review of the effect of alloy composition on the growth rates of scales formed during oxidation of gamma titanium aluminide alloys, Materials Science and Engineering A 338 (2002) 108-125.
• [8] K. P. Rao, Y. J. Du, J. C. Y. Chung, K. C. Lau, In situ composite formation in TiAlSi ternary system, Journal of Materials Processing Technology 89-90 (1999) 361-366.
• [9] B. G. Kim, G. M. Kim, J. C. Kim, Oxidation behavior of TiAl-X (X=Cr, V, Si, Mo or Nb) intermetallics at elevated temperature, Scripta Metallurgica et Materialia 33/7 (1995) 1117-1125.
• [10] M. Góral, G. Moskal, L. Swadźba, The influence of Si on structure of aluminide coatings deposited on TiAl alloy, Journal of Achievements in Materials and Manufacturing Engineering 18 (2006) 463-466.
• [11] M. Góral, G. Moskal, L. Swadźba, The influence of Si on oxidation resistance of aluminide coatings on TiAl alloy, Journal of Achievements in Materials and Manufacturing Engineering 18 (2006) 459-462.
• [12] R. Yang, Y. Y. Cui, L. M. Dong, Q. Jia, Alloy development and shell mould casting of gamma TiAl Journal of Materials Processing Technology 135/2-3 (2003) 179-188.
• [13] T. Tetsui, Gamma Ti aluminides for non-aerospace applications, Current Opinion in Solid State and Materials Science 4/3 (1999) 243-248.
• [14] R. Yang, Y. Y. Cui, L. M. Dong, Q. Jia, Alloy development and shell mould casting of gamma TiAl, Journal of Materials Processing Technology 135/2-3 (2003) 179-188.
• [15] E. Loria, Quo vadis gamma titanium aluminide, Interme-tallics 9/12 (2001) 997-1001.