Abstract
A three-layer Ta2O5-containing coating was successfully fabricated by laser cladding on a pure Ta substrate. The maximum thickness of such a coating is about 1.6 mm. The microstructure, phase constitution and elemental distribution in the coating were investigated. Results show that the coating has been metallurgically bonded to the Ta substrate and the microstructure exhibits a graded change along the deposition direction from Ta substrate to the top of coating. In the layers I and II of the graded coating, the microstructure evolution can be confirmed as a result of hypomonotectic reaction, but in the layer III it was formed by hypermonotectic reaction. At the top of coating, the microstructure was still homogeneous although liquid phase separation had occurred, which can be attributed to the fact that the O-rich droplets do not have enough time to float at high cooling rate. The theoretical calculation results show that during laser cladding, the solidification time of the melt pool was less than 0.1 s, which fits well with the results from the experiment.
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Chaneliere C, Autran J L, Devine R A B. Tantalum pentoxide (Ta2O5) thin films for advanced dielectric applications. Marer. Sci. Eng. R., 1998, 22: 269–322.
Li Y, Zhao T T, Wei S B, et al. Effect of Ta2O5/TiO2 thin film on mechanical properties. corrosion and cell behavior of the NiTi alloy implanted with tantalum. Mater. Sci. Eng. C, 2010, 30: 1227–1235.
Shang P, Xiong S M, Li L H, et al. Investigation on thermal stability of Ta2O5, TiO2 and Al2O3 coatings for application at high temperature. Appl. Surf. Sci., 2013, 285: 713–720.
Franco F D, Santamaria M, Quarto F D, et al. The influence of nitrogen incorporation on the optical properties of anodic Ta2O5. Electrochim. Acta, 2012, 59: 382–386.
Lu T, Wen J, Qian S, et al. Enhanced osteointegration on tantalum-implanted polyetheretherketone surface with bone-like elastic modulus. Biomater, 2015, 51:173–183.
Long Z Y, Mitsuo N, Toshikazu A, et al. Corrosion resistance and biocompatibility of Ti-Ta alloys for biomedical applications. Mater. Sci. Eng. A, 2005, 398: 28–36.
Geetha M, Singh A K, Asokamani R, et al. Ti based biomaterials, the ultimate choice for orthopaedic implants–A review. Prog. Mater. Sci, 2009, 54: 397–425.
Taheri M, Zahrani E M. Effect of novel thermal oxidation process on wear resistance of commercial pure titanium. Surf. Eng., 2008, 24(6): 475–478.
Wiecinski P, Smolik J, Garbacz H, et al. Microstructure and mechanical properties of nanostructure multilayer CrN/Cr coatings on titanium alloy. Thin Solid Films, 2011, 519(12): 4069–4073.
Richard C, Kowandy C, Landoulsi J, et al. Corrosion and wear behavior of thermally sprayed nano ceramic coatings on commercially pure titanium and Ti-13Nb-13Zr substrates. Int. J. f Refract. Met. H., 2010, 28(1):115–123.
Fei C, Hai Z, Chen C, et al. Study on the tribological performance of ceramic coatings on titanium alloy surfaces obtained through microarc oxidation. Prog. Org. Coat., 2009, 64(2-3): 264–267.
Tian Y S, Chen C Z, Li S T, et al. Research progress on laser surface modification of titanium alloys. Appl. Surf. Sci., 2005, 242(1-2): 177–184.
A Zielinski, Jazdzewska M, Lubinski J, et al. Effects of laser remelting at cryogenic conditions on microstructure and wear resistance of the Ti6Al4V alloy applied in medicine. Solid State Phenom., 2012, 183: 215–224.
Zhang J B, Fan D, Sun Y N, et al. Microstructure and hardness of the laser surface treated titanium. Key Eng. Mat., 2007, 353-358: 1745–1748.
Bao R L, Yu H J, Chen C Z, et al. Development of laser cladding wear-resistant coating on titanium alloys. Surf. Rev. and Lett., 2006, 13(5): 645–654.
Garg S P, Krishnamurthy N, Awasthi A, et al. The O-Ta (oxygentantalum) system. J. Phase Equilibria, 1996, 17(1): 63–77.
Ratke L, Alkemper J. Modelling of phase separation in liquids with a miscibility gap. Advances in Colloid and Interface Science, 1995, 58:151–170.
John F. Partical Differential Equations. 4th ed. Wiley and Sons, NY, 1982.
Kurz W, Giovanola B, Trivedi R. Theory of microstructural development during rapid solidification. Acta Metall. Mater., 1986, 34: 823–830.
Eric A B. Smithells Metals Reference Book. Sixth ed. Robert Hartholl Ltd., 1983: 8–1.
Lima M S F, Goldenstein H. Morphological instability of the austenite growth front in a laserremelted iron-carbon-silicon alloy. J. Cryst. Growth, 2000, 208: 709–716.
Steen W M, Mazumder J. Laser Material Processing, 4th ed. Springer-Verlag London Limited: London, UK, 2010: 317–318.
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Male, born in 1976, assistant professor. His research interests mainly focus on the laser additive manufacturing.
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Yang, Ho., Wang, M., Lin, X. et al. Microstructure evolution and liquid phase separation in Ta-O hypermonotectic melts during laser-cladding. China Foundry 15, 222–227 (2018). https://doi.org/10.1007/s41230-018-8059-5
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DOI: https://doi.org/10.1007/s41230-018-8059-5