Tecnologia em Metalurgia, Materiais e Mineração
https://tecnologiammm.com.br/article/doi/10.4322/2176-1523.20222497
Tecnologia em Metalurgia, Materiais e Mineração
Artigo Original

Influência do tratamento térmico sub-βtrans na dureza e na microestrutura de implantes dentais de Ti-6Al-4V ELI produzidos por manufatura aditiva a laser

Influence of sub-βtrans heat treatment on the hardness and microstructure of Ti-6Al-4V ELI dental implants produced by laser additive manufacturing

José Alex Gonçalves de Galiza, Carlos Nelson Elias, André Rocha Pimenta

Downloads: 1
Views: 109

Resumo


O uso dos implantes dentais de titânio para a reabilitação total ou parcial da função mastigatória é uma prática clínica usual na odontologia. Estes implantes possuem osseointegração e são produzidas por usinagem de barras de titânio.
A possibilidade do emprego da manufatura aditiva (MA) para fabricar peças complexas abre a possibilidade da fabricação de implantes personalizados. Uma desvantagem da MA dos metais é que os produtos necessitam de tratamento térmico para alívio das tensões residuais oriundas do rápido resfriamento durante a manufatura. O objetivo do presente trabalho foi produzir implantes dentais de Ti-6Al-4V ELI por MA e analisar a influência do tratamento térmico sub-βtrans na dureza e na microestrutura. Os implantes foram submetidos aos tratamentos térmicos nas temperaturas de 400, 450 e 500 o C, as quais são inferiores à de transformação de fase α-β (sub-βtrans) da liga. Antes e após os tratamentos térmicos foram realizadas análises da microestrutura dos implantes por microscopia óptica e eletrônica de varredura, quantificadas as temperaturas de transformação de fases por calorimetria diferencial de varredura, identificadas as fases por difração de raios-X, medidos os tamanhos dos grãos e determinada a microdureza Vickers. Os dados de microdureza e tamanho dos grãos foram submetidos à análise estatística. Os resultados mostraram que todos os tratamentos térmicos alteraram a microestrutura e a microdureza dos implantes. As alterações mais relevantes na microestrutura foram das amostras tratadas a 500 o C, indicando que este tratamento térmico induz maior alívio de tensões sem redução da dureza dos implantes.

Palavras-chave

Manufatura aditiva; Implante dentário; Microestrutura; Tratamento térmico

Abstract

The use of titanium dental implants for the total or partial rehabilitation of masticatory function is a common clinical practice in dentistry. These implants have osseointegration and are produced by machining titanium bars. The possibility of using additive manufacturing (MA) to make complex parts opens up the possibility of manufacturing custom implants. A disadvantage of the Ti alloy MA is that the products require heat treatment to relieve residual stresses arising from rapid cooling during manufacture. The present work aimed to produce dental implants of Ti-6Al-4V ELI by MA and to analyze the influence of sub-βtrans heat treatment on hardness and microstructure. The implants were subjected to heat treatments at temperatures of 400, 450, and 500 o C, which are inferior to the transformation of the α-β phase (sub-βtrans) of the alloy. Before and after the heat treatments, microstructure analyzes of the implants were performed by optical and scanning electron microscopy, the phase transformation temperatures were quantified by differential scanning calorimetry, the phases were identified by X-ray diffraction and the Vickers microhardness was determined. The microhardness and grain size data were subjected to statistical analysis. The results showed that all heat treatments changed the microstructure and microhardness of the implants. The most relevant changes in the microstructure were in the samples treated at 500 o C, indicating that this heat treatment induces greater stress relief without reducing the hardness of the implants.

Keywords

Additive Manufacturing; Dental implants; Microstructure; Heat treatment.

Referências

1 Yan C, Hao L, Hussein A, Young P. Ti–6Al–4V triply periodic minimal surface structures for bone implants fabricated via selective laser melting. Journal of the Mechanical Behavior of Biomedical Materials. 2015;51:61-73. http://dx.doi.org/10.1016/j.jmbbm.2015.06.024.
2 Konečná R, Kunz L, Bača A, Nicoletto G. Resistance of direct metal laser sintered Ti6Al4V alloy against growth of fatigue cracks. Engineering Fracture Mechanics. 2017;185:82-91. http://dx.doi.org/10.1016/j.engfracmech.2017.03.033.
3 Brunello G, Sivolella S, Meneghello R, Ferroni L, Gardin C, Piattelli A, et al. Powder-based 3D printing for bone tissue engineering. Biotechnology Advances. 2016;34:740-753. http://dx.doi.org/10.1016/j.biotechadv.2016.03.009.
4 Zhai Y, Galarraga H, Lados DA. Microstructure, static properties, and fatigue crack growth mechanisms in Ti-6Al-4V fabricated by additive manufacturing: LENS and EBM. Engineering Failure Analysis. 2016;69:3-14. http://dx.doi.org/10.1016/j.engfailanal.2016.05.036.
5 Thijs L, Verhaeghe F, Craeghs T, Van Humbeeck J, Kruth JP. A study of the microstructural evolution during selective laser melting of Ti-6Al-4V. Acta Materialia. 2010;58:3303-3312. http://dx.doi.org/10.1016/j.actamat.2010.02.004.
6 Ali H, Ghadbeigi H, Mumtaz K. Effect of scanning strategies on residual stress and mechanical properties of Selective Laser Melted Ti6Al4V. Materials Science and Engineering A. 2018;712:175-187. http://dx.doi.org/10.1016/j.msea.2017.11.103.
7 Liu S, Shin YC. Additive manufacturing of Ti6Al4V alloy: a review. Materials & Design. 2019;164:107552. http://dx.doi.org/10.1016/j.matdes.2018.107552. 

8 Kunze K, Etter T, Grässlin J, Shklover V. Texture, anisotropy in microstructure and mechanical properties of IN738LC alloy processed by selective laser melting (SLM). Materials Science and Engineering A. 2015;620:213-222. http://dx.doi.org/10.1016/j.msea.2014.10.003.
9 Kasperovich G, Hausmann J. Improvement of fatigue resistance and ductility of TiAl6V4 processed by selective laser melting. Journal of Materials Processing Technology. 2015;220:202-214. http://dx.doi.org/10.1016/j.jmatprotec.2015.01.025.
10 Brandl E, Greitemeier D. Microstructure of additive layer manufactured Ti–6Al–4V after exceptional post heat treatments. Materials Letters. 2012;81:84-87. http://dx.doi.org/10.1016/j.matlet.2012.04.116.
11 Sieniawski J, Ziaja W, Kubiak K, Motyka M. Microstructure and mechanical properties of high strength two-phase titanium alloys. In: Sieniawski J, Ziaja W, editors. Titanium Alloys - Advances in Properties Control. London: InTech; 2013. https://doi.org/10.5772/56197.
12 Wang Z, Xiao Z, Tse Y, Huang C, Zhang W. Optimization of processing parameters and establishment of a relationship between microstructure and mechanical properties of SLM titanium alloy. Optics & Laser Technology. 2019;112:159-167. http://dx.doi.org/10.1016/j.optlastec.2018.11.014.
13 Wang M, Wu Y, Lu S, Chen T, Zhao Y, Chen H, et al. Fabrication and characterization of selective laser melting printed Ti–6Al–4V alloys subjected to heat treatment for customized implants design. Progress in Natural Science: Materials International. 2016;26:671-677. http://dx.doi.org/10.1016/j.pnsc.2016.12.006.
14 Liu S, Shin YC. Additive manufacturing of Ti6Al4V alloy: a review. Materials & Design. 2019;164:107552. http://dx.doi.org/10.1016/j.matdes.2018.107552.
15 Lerebours A, Vigneron P, Bouvier S, Rassineux A, Bigerelle M, Egles C. Additive manufacturing process creates local surface roughness modifications leading to variation in cell adhesion on multifaceted TiAl6V4 samples. Bioprinting. 2019;16:e00054. http://dx.doi.org/10.1016/j.bprint.2019.e00054.
16 Gil Mur FX, Rodríguez D, Planell JA. Influence of tempering temperature and time on the α′-Ti-6Al-4V martensite. Journal of Alloys and Compounds. 1996;234:287-289. http://dx.doi.org/10.1016/0925-8388(95)02057-8.
17 Etter T, Kunze K, Geiger F, Meidani H. Reduction in mechanical anisotropy through high temperature heat treatment of Hastelloy X processed by Selective Laser Melting (SLM). IOP Conference Series: Materials Science and Engineering. 2015;82:012097. https://doi.org/10.1088/1757-899X/82/1/012097.
18 Associação Brasileira de Normas Técnicas – ABNT. ISO 6507-1 Metallic materials - Vickers hardness test. Part 1: Test method. Rio de Janeiro: ABNT; 2008.
19 Leuders S, Thöne M, Riemer A, Niendorf T, Tröster T, Richard HA, et al. On the mechanical behaviour of titanium alloy TiAl6V4 manufactured by selective laser melting: Fatigue resistance and crack growth performance. International Journal of Fatigue. 2013;48:300-307. http://dx.doi.org/10.1016/j.ijfatigue.2012.11.011.
20 Lütjering G. Influence of processing on microstructure and mechanical properties of (α+β) titanium alloys. Materials Science and Engineering A. 1998;243:32-45. http://dx.doi.org/10.1016/S0921-5093(97)00778-8.
21 Sallica-Leva E, Caram R, Jardini AL, Fogagnolo JB. Ductility improvement due to martensite α′ decomposition in porous Ti–6Al–4V parts produced by selective laser melting for orthopedic implants. Journal of the Mechanical Behavior of Biomedical Materials. 2016;54:149-158. http://dx.doi.org/10.1016/j.jmbbm.2015.09.020.
22 Gil Mur FX, Rodríguez D, Planell JA. Influence of tempering temperature and time on the α′-Ti-6A1-4V martensite. Journal of Alloys and Compounds. 1996;234:287-289. http://dx.doi.org/10.1016/0925-8388(95)02057-8.


Submetido em:
05/11/2020

Aceito em:
16/06/2021

621551b6a953952d232a0be2 tmm Articles
Links & Downloads

Tecnol. Metal. Mater. Min.

Share this page
Page Sections