The 311th MANA Special Seminar

Prof. Masahiro Yoshimura

Date February 4, Monday
Time 13:30-14:15
Place Auditorium, 1F, WPI - MANA Bldg., NAMIKI Site, NIMS

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13:30-14:15

Growing Integration Layer [GIL] Strategy: Direct Fabrication of Compositionally, Structurally and Functionally Graded Ceramic Coatings and/or Films from Mother Materials in Solution

We have proposed a novel concept and technology of the formation “Growing Integration Layer” [GIL] between ceramics and metallic materials to improve the adhesion performance. Those GIL(s) can be prepared via integration of ceramic film formation from a component of the metallic materials by chemical and /or electrochemical reactions in a solution at low temperature of RT-200℃. They have particular features: 1) Widely diffused interface(s), 2) Continuously graded layers grown from the bulk(substrate), 3) Low temperature process, etc. They are quite different from Layer-by-Layer [LBL] strategy, where every layer is deposited from the Top. BaTiO3 or SrTiO3/TiOx GIL films on Ti plates formed by hydrothermal-electrochemical method showed good adhesion. CaTiO3/Al2O3/Ti2Al GIL films on TiAl exhibited excellent adhesion and anti-oxidation performances: they could be sustained for 10 times cyclic oxidation test at 900℃ in air for 5 hrs.[1] The GIL strategy is effective for many metallic alloys and bulk metallic glassed because they generally contain active component(s). On a Ti-base Bulk Metallic Glass, we could succeed to prepare bioactive titanate nano-mesh layer by hydrothermal-electrochemical techniques at 90-120℃[2]. Similarly, bioactive oxide layers could be prepared on different Bulk Metallic Glasses. Carbon film formation on SiC[3] can be regarded as one of GIL methods. The GIL methods are typical “Soft Process” and “Green Process”using aqueous solutions, and applicable for various functional and structural ceramics layers.

Refenences
[1] M. Yoshimura et al., Mater. Sci. Eng. B, 148, 2-6(2008)
[2] N. Sugiyama, M. Yoshimura et al., Acta Biomaterialia, 5, 1367-1373(2009), Mater. Sci. Eng. B, 161, 31-35(2009)
[3] Y. Gogotsi and M. Yoshimura, Nature, 367, 628-630 (1994)

Speaker

Prof. Masahiro Yoshimura, Materials Science & Engineering, National Cheng Kung University, Taiwan

Chair

Dr. Toyohiro Chikyow, MANA PI, MANA, NIMS