Estudo do tratamento de oxidação em diferentes microestruturas da liga de titânio
Study of the treatment of oxidation in different microstructures of the titanium alloy
FabrÃcia Assis Resende Gonçalves, Renata Jesuina Takahash, Danieli Aparecida Pereira Reis
Resumo
A liga Ti-6Al-4V é a liga de titânio mais usada em aplicações estruturais de engenharia pela combinação de resistência mecânica em altas temperaturas, baixa massa especÃfica e resistência à corrosão. Contudo, uma das limitações da liga é a afinidade do titânio por oxigênio a partir de 600 °C, tornando a liga susceptÃvel à oxidação. Portanto, neste trabalho se estudou a oxidação na liga de titânio (Ti-6Al-4V) com diferentes microestruturas: equiaxial, Widmanstätten, martensÃtica e bimodal obtidas por tratamento térmico. As amostras com as diferentes microestruturas foram submetidas a tratamento térmico de oxidação nas temperaturas de 500, 600, 700 e 800 °C por 48 horas ao ar. Os resultados mostraram que as amostras oxidadas formaram uma pelÃcula de óxido sobre a superfÃcie que foram caracterizadas por microscopia óptica e microscopia eletrônica de varredura, por medição da variação da massa das amostras e por análise de microdureza. A microestrutura Widmanstätten apresentou-se mais resistente à oxidação pela formação de grãos mais grosseiros e formação de pelÃcula de óxidos mais espessos e mais resistentes a deformação localizada.
Palavras-chave
Abstract
The Ti-6Al-4V alloy is the most commonly used titanium alloy in structural engineering applications by combining mechanical strength at high temperatures, low specific mass, and corrosion resistance. However, one of the limitations of the alloy is the affinity of titanium for oxygen from 600 °C, making the alloy susceptible to oxidation. The purpose of this work was to study the oxidation of titanium alloys (Ti-6Al-4V) with different microstructures: equiaxial, Widmanstätten, martensite, and bimodal, which were formed from heat treatment. The samples with different microstructures were subjected to oxidation heat treatment at temperatures of 500, 600, 700, and 800°C for 48 hours in the air. The oxidized samples formed an oxide film on the surface, which was characterized by optical and scanning electron microscopy, by measuring the mass of the samples and by microhardness analysis. The Widmanstätten microstructure was more resistant to oxidation by the formation of coarser grains and the formation of thicker oxide films and more resistant to localized deformation.
Keywords
References
1 Leyens C, Peters M. Titanium and titanium alloys. 3rd ed. Weinheim: Wiley; 2003.
2 Zhecheva A, Sha W, Malinov S, Long A. Enhancing the microstructure and propertiesof titanium alloys through nitriding and other surface engineering methods. Surface and Coatings Technology. 2005;200:2192-2207.
3 Reis AG, Reis DAP, Moura Neto C, Barboza MJR, Oñoro J. Creep behavior and surface characterization of a laser surface nitrided Ti–6Al–4V alloy. Materials Science and Engineering A. 2013;577:48-53.
4 Oliveira AC, Oliveira RM, Reis DAP, Carreri FC. Effect of nitrogen high temperature plasma based ion implantation on the creep behavior of Ti-6Al-4V alloy. Applied Surface Science. 2014;311:239-244.
5 Reis DAP, Reis AG, Yogi LM, Silva MM, Ueda M, Zepka S. Comparation between Laser Surface Nitriding and Nitrogen Plasma Immersion Ion Implantation (N-PIII) on Creep Behavior of Ti-6Al-4V Alloy. Materials Science Forum. 2014;802:462-466.
6 Briguente LANS, Briguente FP, Reis DAP, Moura Neto C, Resende FA. Avaliação do comportamento em fluência da liga Ti-6Al-4V com estrutura martensÃtica e equiaxial a 600°C. Tecnologia em Metalurgia. Materiais e Mineração (Impresso). 2013;10:324-328.
7 Sugahara T, Martins GV, Montoro FE, Merij Neto A, Massi M, da Silva Sobrinho AS, et al. Creep behavior evaluation and characterization of SiC film with Cr interlayer deposited by HiPIMS in Ti-6Al-4V alloy. Surface and Coatings Technology. 2017;309:410-416.
8 Sugahara T, Reis DAP, Moura Neto C, Barboza MJR, Perez EAC, Piorino Neto F, et al. The effect of Widmanstätten and equiaxed microestructures of Ti-6Al-4V on the oxidation rate and creep behavior. Materials Science Forum. 2010;636/637:657-662.
9 Reis DAP, Silva CRM, Nono MCA, Barboza MJR, Piorino Neto F, Perez EAC. Plasma-Sprayed Coatings for Oxidation Protection on Creep of the Ti-6Al-4V Alloy. Materials at High Temperatures. 2005;22:449-452.
10 Reis DAP, Moura Neto C, Silva CRM, Barboza MJR, Piorino Neto F. Effect of coating on the creep behavior of the Ti–6Al–4V alloy. Materials Science and Engineering A. 2008;486:421-426.
11 Donachie MJ. Titanium: A Technical Guide. 2nd ed. Novelty, OH: ASM International; 2000.
12 Froes FH. Titanium: physical metallurgy, processing, and applications. 1st Ed. Novelty, OH: ASM International; 2015.
13 Seco FJ, Irisarri AM. Creep failure mechanisms of a Ti-6Al-4V thick plate. Fatigue & Fracture of Engineering Materials & Structures. 2001;24:741-750.
14. American Society of Testing and Materials. Annual Book of ASTM Standards. West Conshohocken: ASTM; 1995.
15 Sahoo R, Jha BB, Sahoo TK. Effect of Microstructure on the Creep Properties of Ti–6Al–4V Alloys: An Analysis. Transactions of the Indian Institute of Metals. 2018;71:1573-1582.
16 Jeng SC. Oxidation behavior and microstructural evolution of hot-dipped aluminum coating on Ti-6Al-4V alloy at 800°C. Surface and Coatings Technology. 2013;235:867-874.
17 Luan JH, Jiao ZB, Chen G, Liu CT. Improved ductility and oxidation resistance of cast Ti-6Al-4V alloys by microalloying. Journal of Alloys and Compounds. 2014;602:235-240.
18 Lütjering G. Influence of processing on microstructure and mechanical properties of (α+β) titanium alloys. Materials Science and Engineering A. 1998;243:32-45.
19 Yogi LM, Sugahara T, Moura Neto C, Reis DAP, Piorino Neto F, Barboza MJR. Efeito do tratamento térmico na fluência da liga Ti-6Al-4V. Revista Brasileira de Aplicações de Vácuo. 2008;27:189-194.
20 Poquillon D, Armand C, Huez J. Oxidation and oxygen diffusion in Ti-6al-4V alloy: Improving measurements during SIMS analysis by rotating the sample. Oxidation of Metals. 2013;79:249-259.
21 Ramachandran M, Mantha D, Williams C, Reddy RG. Oxidation and diffusion in Ti-Al-(Mo, Nb) intermetallics. Metallurgical and Materials Transactions. A, Physical Metallurgy and Materials Science. 2011;42:202-210.
22 Kofstad P. High-temperature oxidation of titanium. Journal of the Less Common Metals. 1967;12:449-464.
Submitted date:
06/10/2019
Accepted date:
09/29/2020
Facebook
Google+
Twitter
LinkedIn
Mendeley
StumbleUpon
CiteULike
Reddit
Email