Characterization of Sputter-Deposited NiTi Thin Film by Nanoindentation

2015 ◽  
Vol 662 ◽  
pp. 87-90
Author(s):  
Petr Haušild ◽  
Michal Landa

NiTi shape memory alloy thin film sputter-deposited on a large scale silicon wafer was characterized by means of instrumented (depth-sensing) indentation technique. Thickness of deposited thin film was measured by calotest device. Microstructure of thin film was observed using differential interference (Nomarski) contrast. It was shown that the local mechanical properties are different in areas containing different phases (austenite and martensite) according to different deposition conditions (kinetic energy of deposited atoms when impacting the substrate surface).

1999 ◽  
Vol 11 (4) ◽  
pp. 258-262
Author(s):  
Seiji Shimizu ◽  
◽  
Katsutoshi Kuribayashi

We studied the transformation and mechanical properties of Ti- 54.8-51.6 at % Ni shape memory alloy thin film actuators sputter-deposited at different argon pressures of 0.47-3.4 Pa. The higher the argon pressure, the lower the nickel composition. TiNi thin films were crystallized at 800C for 10min, aged at 400C for 6h, and analyzed by differential scanning calorimetry and tensile tests. All films showed 2-step transformation of martensite, R, and austenite phases. The maximum generative stress of 365MPa was obtained when the TiNi thin film actuator deposited at 2.0Pa was heated electrically to 30A/mm2 after deformation of 3.0% at room temperature.


Author(s):  
Gyeung Ho Kim ◽  
Mehmet Sarikaya ◽  
D. L. Milius ◽  
I. A. Aksay

Cermets are designed to optimize the mechanical properties of ceramics (hard and strong component) and metals (ductile and tough component) into one system. However, the processing of such systems is a problem in obtaining fully dense composite without deleterious reaction products. In the lightweight (2.65 g/cc) B4C-Al cermet, many of the processing problems have been circumvented. It is now possible to process fully dense B4C-Al cermet with tailored microstructures and achieve unique combination of mechanical properties (fracture strength of over 600 MPa and fracture toughness of 12 MPa-m1/2). In this paper, microstructure and fractography of B4C-Al cermets, tested under dynamic and static loading conditions, are described.The cermet is prepared by infiltration of Al at 1150°C into partially sintered B4C compact under vacuum to full density. Fracture surface replicas were prepared by using cellulose acetate and thin-film carbon deposition. Samples were observed with a Philips 3000 at 100 kV.


2008 ◽  
Vol 62 (17-18) ◽  
pp. 2791-2794 ◽  
Author(s):  
T. Shahrabi ◽  
S. Sanjabi ◽  
E. Saebnoori ◽  
Z.H. Barber

Coatings ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 1212
Author(s):  
Pei-Hua Tsai ◽  
Chung-I Lee ◽  
Sin-Mao Song ◽  
Yu-Chin Liao ◽  
Tsung-Hsiung Li ◽  
...  

Mg-based bulk metallic glass (BMG) and its composite (BMGC) can be excellent candidates as lightweight structure materials, but lack of anti-corrosion ability may restrict their application. In order to enhance the natural weak point of Mg-based BMGC, a 200-nm thick Zr-based metallic glass thin film (MGTF) ((Zr53Cu30Ni9Al8)99.5Si0.5) was applied and its mechanical properties as well as its corrosion resistance were appraised. The results of a 3-point bending test revealed that the flexural strength of the Mg-based BMGC with 200-nm thick Zr-based MGTF coating can be greatly enhanced from 180 to 254 MPa. We propose that the Zr-based MGTF coating can help to cover any small defects of a substrate surface, provide a protecting layer to prevent stress concentration, and cease crack initiation from the specimen surface during bending tests. Moreover, the results of anti-corrosion behavior analysis revealed a similar trend between the Mg-based BMG, Mg-based BMGC, and Mg-based BMGC with Zr-based MGTF coating in 0.9 wt.% sodium chloride solution. The readings show a positive effect with the Zr-based MGTF coating. Therefore, the 200-nm thick Zr-based MGTF coating is a promising solution to provide protection for both mechanical and anti-corrosion behaviors of Mg-based BMGC and reinforce its capability as structure material in island environments.


2020 ◽  
Author(s):  
Alessandro Frigeri ◽  
Maria Cristina De Sanctis ◽  
Francesca Altieri ◽  
Simone De Angelis ◽  
Marco Ferrari ◽  
...  

<p>The ExoMars Rover and Surface Platform planned for launch in 2022 is a large international cooperation between the European Space Agency and Roscosmos with a scientific contribution from NASA.  Thales Alenia Space is the ExoMars mission industrial prime contractor. </p> <p>Besides sensors and instruments characterizing the surface at large scale, the ExoMars’ rover Rosalind Franklin payload features some experiments devoted specifically to the characterization of the first few meters of the Martian subsurface. These experiments are particularly critical for the main ExoMars objective of detecting traces of present or past life forms on Mars, which may have been preserved within the shallow Martian underground [1].</p> <p>Rosalind Franklin will be able to perform both non-invasive geophysical imaging of the underground [2] and subsurface <em>in situ</em> measurements thanks to the Drill unit installed on the rover. The Drill has been developed by Leonardo and its purposes are 1) to collect core samples to be analyzed in the Analytical Laboratory Drawer (ALD) onboard the Rover and 2) to drive the miniaturized spectrometer Ma_MISS within the borehole.   </p> <p>Ma_MISS (Mars Multispectral Imager for Subsurface Studies, [3]) will collect mineralogic measurements from the rocks exposed into the borehole created by the Drill with a spatial resolution of 120 μm down to 2 meters into the Martian subsurface.</p> <p>Rocks are composed of grains of minerals, and their reaction to an applied stress is related to the mechanical behavior of the minerals that compose the rock itself. The mechanical properties of a mineral depend mainly on the strength of the chemical bonds, the orientation of crystals, and the number of impurities in the crystal lattice.</p> <p>In this context, the integration of Ma_MISS measurements and drill telemetry are of great importance.  The mechanical properties of rocks coupled with their mineralogic composition provide a rich source of information to characterize the nature of rocks being explored by ExoMars rover’s drilling activity.</p> <p>Within our study, we are starting to collect telemetry recorded during the Drill unit tests on several samples ranging from sedimentary to volcanic rocks with varying degrees of weathering and water content.  In this first phase of the study, we focused our attention on the variation of torque and penetration speed between different samples, which have been found to be indicative of a particular type of rock or group of rocks and their water content.  </p> <p>We are planning to analyze the same rocks with the Ma_MISS breadboard creating the link between the mineralogy and the mechanical response of the Drill.      </p> <p>This will put the base for a more comprehensive and rich characterization of the <em>in situ</em> subsurface observation by Rosalind Franklin planned at Oxia Planum, Mars in 2023. </p> <p> </p> <p><strong>Acknowledgments: </strong>We thank the European Space Agency (ESA) for developing the ExoMars Project, ROSCOSMOS and Thales Alenia Space for rover development, and Italian Space Agency (ASI) for funding the Ma_MISS experiment (ASI-INAF contract n.2017-48-H.0 for ExoMars MA_MISS phase E/science).</p> <p> </p> <p><strong>References</strong></p> <p>[1] Vago et al., 2017. Astrobiology, 17 6-7. [2] Ciarletti et al., 2017. Astrobiology, 17 6-7. [3] De Sanctis et al., 2017. Astrobiology, 17 6-7.</p>


1994 ◽  
Vol 345 ◽  
Author(s):  
Paul H. Holloway ◽  
J.-E. Yu ◽  
Phillip Rack ◽  
Joseph Sebastian ◽  
Sean Jones ◽  
...  

AbstractFollowing a description of the purpose and participating members in the Phosphor Technology Center of Excellence, research on the growth and characterization of modulation doped ZnS:Mn and of Ca0.95Sr0.05Ga2S4:6%Ce are reported. ZnS:Mn has been grown using MOCVD and incorporation of Mn in 1 to 5 layers from 5 to 20 nm thick separated by layers of pure ZnS from 5 to 50 nm thick. This is shown to result in lower threshold voltages for ACTFELD displays. The luminescence spectra from sputter deposited, cerium-doped thiogallate thin films were measured and the diffusion of thin ZnS passivation layers versus temperature of heat treatment was discussed.


1994 ◽  
Vol 359 ◽  
Author(s):  
Kiyoshi Yase ◽  
Takuya Saraya ◽  
Kazuhiro Kudo

ABSTRACTFullerene C60 thin solid films have been fabricated on the (001) surfaces of alkali halides (NaCl, KCI and KBr) and muscovite by organic molecular beam deposition (OMBD) technique. Pure C60 powder was sublimated from the precisely temperature-controlled K-cell at low pressure (10−7 Torr) and deposited onto the substrates kept in the range 125 –300 °C. Increasing both the temperature of K-cell and the substrate temperature, fine crystals grow with different size, shape and distance between neighbors. The dependence of the size and density of island crystals on the deposition conditions revealed the mechanism of crystal growth and the effect of interaction between molecules and substrate surface.


1996 ◽  
Vol 441 ◽  
Author(s):  
Dong-Yeon Park ◽  
Dong-Su Lee ◽  
Min Hong Kim ◽  
Tae-Soon Park ◽  
Hyun-Jung Woo ◽  
...  

AbstractPlatinum(Pt) films were sputter-deposited on Si02/Si substrates under the mixed gas atmosphere of Ar and O2. Under certain deposition conditions, the films were oriented such that the (100) direction is normal to the substrate surface. The formation of the (100) texture was affected by the gas pressure and film thickness. After annealing at 650 °C for 1 hour, (100) oriented Pt films with the resistivity of pure Pt were obtained. The annealed Pt films all passed a tape adhesion test and had no defects such as hillocks or pinholes. The experimental results from this work are presented.


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