The thermodynamics of TiN precipitation in liquid steel of 430 ferrite stainless steel has been calculated to find out the condition of TiN precipitation during the initial solidification stage. The difference in the ...The thermodynamics of TiN precipitation in liquid steel of 430 ferrite stainless steel has been calculated to find out the condition of TiN precipitation during the initial solidification stage. The difference in the solidification structure of 430 ferrite stainless steel has been discussed through comparative tests of vacuum induction furnace melting with different contents of Ti. It has been found that the equiaxed grain proportion can be increased from 20% to 69% as the content of Ti from 0.1% up to 0. 4%. The size of the TiN particles precipitated is 1-3 μm and the number of TiN particles is about （200- 300）/μm^2. It is found that the effect of using TiN to refine the solidification structure has been confirmed under the strict process condition used for 430 ferrite stainless steel.展开更多
Titanium nitride ceramic thin films on 317L stainless steel(SS317L) substrate were deposited by Ion Beam Assisted Deposition (IBAD). The composition of the TiN films were investigated by Auger electron spectroscopy(AE...Titanium nitride ceramic thin films on 317L stainless steel(SS317L) substrate were deposited by Ion Beam Assisted Deposition (IBAD). The composition of the TiN films were investigated by Auger electron spectroscopy(AES), while the preferential orientation of the deposited film and phase composition were determined by X-ray diffraction(XRD). Adhesion was measured through Micro Scratch Tester(MST), and the corrosion resistance was evaluated by the electrochemical corrosion experiments in Hamk’s simulated human plasma. Specially, the biocompatibility of SS317L and TiN thin films were studied with fibroblast and marrow cell cultures in vitro. The results show that TiN thin films deposited on SS317L by means of IBAD can make remarkable changes on the structure and properties of the surface. At 37℃ Hank’s simulated plasma, free corrosion potential (E corr ) and breakthrough potential of pitting corrosion (E b) were both improved by coating TiN films . The culture results show that ion beam assisted TiN coatings exhibit a higher degree of cytocompatibility than that of SS317L and the cells grow better on those proper rough surfaces.展开更多
By taking advantage of the absence of diffraction limit restrictions in plasmonic structures,strong modal confinement is made possible,paving the way for improved optical processes and miniaturized photonic circuit in...By taking advantage of the absence of diffraction limit restrictions in plasmonic structures,strong modal confinement is made possible,paving the way for improved optical processes and miniaturized photonic circuit integration.Indium tin oxide(ITO)has emerged as a promising plasmonic material that serves as a relatively low-carrier density Drude metal by its electro-optic tunability and versatility as an integrative oxide.We herein demonstrate the facile integration of SiO_(2)/ITO heterointerfaces into metal-insulator-semiconductor(MIS)electro-optic structures.The first MIS device employs a SiO_(2)/ITO heterostructure grown on thin polycrystalline titanium nitride(poly-TiN)and capped at the ITO side with thin aluminum(Al)film contact electrode.The TiN interlayer acts as a bottom electrode,forming a metal-insulator-semiconductor-metal(MISM)heterojunction device,and grows directly on(100)-oriented silicon(Si).This MISM device enables one to examine the electrical properties of semiconductive ITO layers.The second MIS device incorporates a semiconductive ITO layer with a SiO_(2)dielectric spacer implemented on a silicon-on-insulator(SOI)platform,forming a graded-index coupled hybrid plasmonic waveguide(CHPW)modulator.This device architecture represents a crucial step towards realizing plasmonic modulation using oxide materials.The CHPW device performance presented herein provides a proof-of-concept that demonstrates the advantages offered by such device topology to perform optical modulation via charge carrier dispersion.The graded-index CHPW can be dynamically reconfigured for amplitude,phase,or 4-quadrature amplitude modulation utilizing a triode-like biasing strategy.It exhibited extinction ratio(ER)and insertion loss(IL)levels of around 1 dB/μm and 0.128 dB/μm,respectively,for a 10μm waveguide length.展开更多
基金The National Basic Research Program of China (2004CB619107)
文摘The thermodynamics of TiN precipitation in liquid steel of 430 ferrite stainless steel has been calculated to find out the condition of TiN precipitation during the initial solidification stage. The difference in the solidification structure of 430 ferrite stainless steel has been discussed through comparative tests of vacuum induction furnace melting with different contents of Ti. It has been found that the equiaxed grain proportion can be increased from 20% to 69% as the content of Ti from 0.1% up to 0. 4%. The size of the TiN particles precipitated is 1-3 μm and the number of TiN particles is about （200- 300）/μm^2. It is found that the effect of using TiN to refine the solidification structure has been confirmed under the strict process condition used for 430 ferrite stainless steel.
基金This project is supported by Tianjin Nature Fundation (contract No:0 2 36 136 11)
文摘Titanium nitride ceramic thin films on 317L stainless steel(SS317L) substrate were deposited by Ion Beam Assisted Deposition (IBAD). The composition of the TiN films were investigated by Auger electron spectroscopy(AES), while the preferential orientation of the deposited film and phase composition were determined by X-ray diffraction(XRD). Adhesion was measured through Micro Scratch Tester(MST), and the corrosion resistance was evaluated by the electrochemical corrosion experiments in Hamk’s simulated human plasma. Specially, the biocompatibility of SS317L and TiN thin films were studied with fibroblast and marrow cell cultures in vitro. The results show that TiN thin films deposited on SS317L by means of IBAD can make remarkable changes on the structure and properties of the surface. At 37℃ Hank’s simulated plasma, free corrosion potential (E corr ) and breakthrough potential of pitting corrosion (E b) were both improved by coating TiN films . The culture results show that ion beam assisted TiN coatings exhibit a higher degree of cytocompatibility than that of SS317L and the cells grow better on those proper rough surfaces.
基金supported by the Natural Sciences and Engineering Research Council of Canada.
文摘By taking advantage of the absence of diffraction limit restrictions in plasmonic structures,strong modal confinement is made possible,paving the way for improved optical processes and miniaturized photonic circuit integration.Indium tin oxide(ITO)has emerged as a promising plasmonic material that serves as a relatively low-carrier density Drude metal by its electro-optic tunability and versatility as an integrative oxide.We herein demonstrate the facile integration of SiO_(2)/ITO heterointerfaces into metal-insulator-semiconductor(MIS)electro-optic structures.The first MIS device employs a SiO_(2)/ITO heterostructure grown on thin polycrystalline titanium nitride(poly-TiN)and capped at the ITO side with thin aluminum(Al)film contact electrode.The TiN interlayer acts as a bottom electrode,forming a metal-insulator-semiconductor-metal(MISM)heterojunction device,and grows directly on(100)-oriented silicon(Si).This MISM device enables one to examine the electrical properties of semiconductive ITO layers.The second MIS device incorporates a semiconductive ITO layer with a SiO_(2)dielectric spacer implemented on a silicon-on-insulator(SOI)platform,forming a graded-index coupled hybrid plasmonic waveguide(CHPW)modulator.This device architecture represents a crucial step towards realizing plasmonic modulation using oxide materials.The CHPW device performance presented herein provides a proof-of-concept that demonstrates the advantages offered by such device topology to perform optical modulation via charge carrier dispersion.The graded-index CHPW can be dynamically reconfigured for amplitude,phase,or 4-quadrature amplitude modulation utilizing a triode-like biasing strategy.It exhibited extinction ratio(ER)and insertion loss(IL)levels of around 1 dB/μm and 0.128 dB/μm,respectively,for a 10μm waveguide length.
