iosr-JMCE   Volume-2 ~ Issue-3

Abstract: Atomic force microscope (AFM) is successfully utilized to image a broad range of thin film specimens because it can image nonconductive and soft material. Since the invention of the AFM, a lot of progress has been made in imaging thin films. Operation at low temperatures brings the benefits of low thermal drift and low thermal noise, which are required for high-resolution measurements. Due to all these benefits cryogenic AFM was developed. The system operates at liquid nitrogen temperatures, and aims to reduce the main intrinsic resolution reducing effects of AFM imaging by freezing samples and imaging them at sub zero temperatures. Further studies on biomolecules and the effects of sub zero temperatures, especially of ice formation on biomolecules structure need to be carried out before this system is routinely used for molecular imaging. The surface morphology of the thin films of In2O3,ITO and PCMO were studied by Atomic Force Microscopy. AFM showed good surface morphology with decreasing RMS area roughness and Line roughness for all above three materials.
Keywords: Atomic Force Microscope, Vacuum Chamber, LN2 Reservoir, Thin Film

[1] Arantxa Vilalta-Clemente "Principles of Atomic Principles Force Microscopy" ,Physics of Advanced Materials Winter School ,2008, PP.1-10
[2] Binnig, G.; Quate, C. F.; Gerber, Ch., Phys. Rev. Lett. ,1986,PP.56, 930.
[3] Xiaogang Liu,and Hua Zhang., "Scanning Probe Microscopy-Based Nanofabrication for Emerging Applications", 2007
[4] C. Debuschewitz, F. M¨unstermann, V. Kunej, and E. Scheer "A Compact and Versatile Scanning Tunnelling Microscope with High Energy Resolution for Use in a 3He Cryostat" Journal of Low Temperature Physics, Vol. 147, Nos. 3/4, May 2007 ,PP.525-535
[5] D. Erts, A. Lõhmus, R. Lõhmus, H. Olin "Instrumentation of STM and AFM combined with transmission electron microscope" Third International Conference on Non-Contact Atomic Force Microscopy, July 16–19, 2000, Hamburg, Germany PP.S71-S74
[6] Alexandra Radenovic´, "A low-temperature ultrahigh vacuum atomic force microscope for biological applications", Review Of Scientific Instruments Volume 74 ,2002,,PP.1022-1025
[7] Ian James Turner, "AFM investigations of critical interactions in the Bacillus primosome and Cryogenic AFM a new tool for structural biology", Thesis submitted to The University of Nottingham for the degree of Doctor of Philosophy,2005, PP.136-153
[8] Changyi Li "Cryogenic Atomic Force Microscope For Characterization Of Nanostructures"Thesis submitted to the Faculty of the Graduate School of the University of Maryland,2005, PP.1-49
[9] Keiichi Nakamoto, C. B. Mooney and Masashi Iwatsuki "Development of low-temperature and high vacuum atomic force microscope with freeze–fracture function"Review Of Scientific Instruments Volume 72-2, 2001 ,PP.1445-1448
[10] N. Wintjes, M. Lange, D. van Vörden, H. Karacuban, D. Utzat, and R. Möllera _ "Very compact design for a low-temperature tuning fork atomic force Microscope American Vacuum Society", 2010, PP.C4E21- C4E24

Abstract: The analytical design of the hybrid composite predicts its tensile properties at different fiber orientation using classical lamination theory. The critical volume fraction of the high elongation fiberyields 0.39 which defines the composite of minimum strength. The high elongation fiber (PET) contributes more in raising the hybrid composite strengthwhile the low elongation fiber (Kenaf) increases the composite modulus more inthe longitudinal direction. Six layers hybrid composite laminates were analyzed. The stacking sequence used was symmetric angle ply (00, 450, 900) with an overall thickness of 12mm .The thermal expansion coefficient of the laminate increases more than that of the individual ply. The overall analytical results confirm that thehybrid composite tensile properties haveincreased significantly as compared to single fiber reinforced composite.
Key Words: Composite, Hybrid, Laminate, Ply,Matrix, fiber, Tensile, Strength

[1] G. H. Fan, L. Geng, Z. H. Lai, G. S. Wang " preparation of hybrid composite based on BaPb03 + Al18B4033/606 1 Al system", Journals of Alloys and Compounds Volume 482, Issue 1-2, PP:512-516, 2009.
[2] A. Panigrahi, S. R. Mallick " characterization of hybrid FRP composite with hydrothermal exposure under varied ambient conditions" Department of metallurgical and materials engineering, National Institute of Technology Rourkela, PP: 8-10, 2008
[3] JEC, "high performance bio composites‟ JEC composite magazines No. 55, 2010.
[4] U.A. Khashaba and M. A. Seif "Journal of Composite Structures" 74PP: 440, 2006.
[5] W. L. Lai and M. Mariatti, "journal of Reinforced Plastics" 27 PP: 925, 2008.
[6] M. A. Maleque, F. Y. Belal and S.M. Sapuan,The Arabian Journal for ScienceAnd engineering 32 PP: 359, 2007.
[7] H. T. Kuan, W. Cantwell and H. MdAkil, The mechanical properties of hybrid composite Based on self reinforced polypropylene‟ Malaysian Polymer journal Vol. 4 No. 2 PP: 71- 80 2009.
[8] K. Sabeel Ahmed, S. Vijayarangan& A.C.B. Naidu, Journal of materials and design, 28 PP: 2287, 2007.
[9] S. Panthapulakkal, & M. Sain , "Injection-molded short Hemp fibre/Glass fibre reinforced polypropylene hybrid composites-Mechanical, Water absorption and thermal properties" Journal of Applied Polymer Science Vol. 103, Wiley Periodicals, Inc. PP: 2432-2441, 2006.
[10] Singh V. K , Gope P. C. , ChauhanSakshi&Bisht Deepak Singh "Mechanical properties of banana fibre based Bio hybrid composite" J. Mater. Environ Sci. 3 (1) , PP: 185-194, 2012.

Abstract: This paper discusses a major application of flexible micro actuators in Micro Air Vehicles (MAV). Design, Kinematics, flapping patterns, performance tests of flapping wing mechanism which replicates dragonfly and corresponding results are discussed in this paper. This paper also discusses artificial foldable wing models by mimicking the unfolding/folding of beetle hind wing in which the actuation is triggered by electrically activated Shape Memory Alloy (SMA) wires. Keywords: Micro Air Vehicles, Modified slider-crank (MSC), Flapping patterns, Hind wing, Shape Memory Alloy

[1] Hui Hu1 and Anand Gopa Kumar- An Experimental Study of Flexible Membrane Wings in Flapping Flight - Iowa State University, Ames, Iowa, 50011,Gregg Abate3,Air Force Research Laboratory, Elgin Air Force Base, Florida.
[2] http://en.wikipedia.org/wiki/Micro_air_vehicle
[3] helly A. Migita - Effects of low Reynolds numbers on the aerodynamics of micro air vehicles - Department of Mechanical Engineering University of Hawaii at Manoa Honolulu, HI 96822.
[4] Michael A.A. Fenelon, Tomonari Furukawa - Design of an active flapping wing mechanism and a micro aerial vehicle using a rotary actuator - Institute for Robotics and Intelligent Systems (Centre for Artificial Intelligence and Robotics), DRDO, Bangalore 560093, India b Department of Mechanical Engineering, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA.
[5] Muhammad A, Park H C, Hwang D Y, Byun D, Goo N S - Mimicking unfolding motion of a beetle hind wing - Chinese Science Bulletin, 2009, 54, 2416–2424.
[6] Improvement of Artificial Foldable Wing Models by Mimicking the Unfolding/Folding Mechanism of a Beetle Hind Wing .Azhar Muhammad1,2, Quoc Viet Nguyen1,2, Hoon Cheol Park1,2,4, Do Y. Hwang4, Doyoung Byun2,3,4, Nam Seo Goo1,2,4.
[7] Haas F, Wootton R J - Two basic mechanisms in insect wing folding - In proceedings of the royal society of London , 1996, 263: 1651 1658

Abstract: Helical compression springs are used generally in fuel injection system of diesel engines, where it undergoes cyclic loading for more than 108 numbers of cycles. In order to predict probable failure positions in helical compression springs, used in fuel injection system, along the length of the spring at inner side, finite element analyses was carried out, using ABAQUS 6.10. The simulation results show an oscillatory behaviour of stresses along the length at inner side. It was confirmed that the oscillation was due to bending involved with compression. It was also revealed that the bending was due to the geometry of springs. Shear stresses along the length of the spring were found to be asymmetrical and with local maxims at starting of each middle coil. The asymmetry was due to the end coil smaller than 360 degrees.
Keywords- Helical compression springs, Maximum shear stress, Finite element analysis

[1] Kaiser B., Pyttel B., Berger C., VHCF-behavior of helical compression springs made of different materials, International Journal of Fatigue, 33, 2011, 23-32
[2] A. M. Wahl, Mechanical Springs( Macgraw Hill Book company. Inc., Second Edition, New York, 1963)
[3] Bergstraesser, M., Die Beanspruchung zylindrischer Schraubenfedern , ZVDI, 77, 1933, 198
[4] Ancker C.J., Goodier, J., N., Theory of pitch and curvature correction for the Helical Springs-1, Journal of Applied Mechanics, 1958, 471.