scholarly journals Micromechanical properties of consecutive layers in specialized insect cuticle: the gula of Pachnoda marginata (Coleoptera, Scarabaeidae) and the infrared sensilla of Melanophila acuminata (Coleoptera, Buprestidae)

2008 ◽  
Vol 211 (16) ◽  
pp. 2576-2583 ◽  
Author(s):  
M. Muller ◽  
M. Olek ◽  
M. Giersig ◽  
H. Schmitz
Keyword(s):  
Insect Cuticle ◽  
Micromechanical Properties ◽  
Melanophila Acuminata

Reconstruction of Chitin-Protein Complexes Using Correlation Averaging Methods: Ovipositor of the Ichneumon Fly Megarhyssa

1980 ◽  
Vol 38 ◽  
pp. 38-39
Author(s):  
L. T. Germinario ◽  
J. Blackwell ◽  
J. Frank
Keyword(s):  
Protein Complexes ◽  
Hexagonal Lattice ◽  
Uranyl Acetate ◽  
Optical Diffraction ◽  
Insect Cuticle ◽  
High Dose ◽  
Wide Angle ◽  
X Ray ◽  
Averaging Methods ◽  
Digital Correlation

This report describes the use of digital correlation and averaging methods 1,2 for the reconstruction of high dose electron micrographs of the chitin-protein complex from Megarhyssa ovipositor. Electron microscopy of uranyl acetate stained insect cuticle has demonstrated a hexagonal array of unstained chitin monofibrils, 2.4−3.0 nm in diameter, in a stained protein matrix3,4. Optical diffraction Indicated a hexagonal lattice with a = 5.1-8.3 nm3 A particularly well ordered complex is found in the ovipositor of the ichneumon fly Megarhyssa: the small angle x-ray data gives a = 7.25 nm, and the wide angle pattern shows that the protein consists of subunits arranged in a 61 helix, with an axial repeat of 3.06 nm5.

AUTOMATIC SYSTEM FOR MICROMECHANICAL PROPERTIES ANALYSIS

1981 ◽  
Vol 42 (C5) ◽  
pp. C5-1129-C5-1134
Author(s):  
S. Etienne ◽  
J. Y. Cavaille ◽  
J. Perez ◽  
M. Salvia
Keyword(s):  
Automatic System ◽  
Micromechanical Properties

scholarly journals Investigation of the Wear Behavior of PVD Coated Carbide Tools during Ti6Al4V Machining with Intensive Built Up Edge Formation

Coatings ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 266
Author(s):  
M.S.I. Chowdhury ◽  
B. Bose ◽  
S. Rawal ◽  
G.S. Fox-Rabinovich ◽  
S.C. Veldhuis
Keyword(s):  
Tool Wear ◽  
Titanium Alloys ◽  
Wear Behavior ◽  
Cutting Temperature ◽  
Ti6al4v Alloy ◽  
Adhesive Interaction ◽  
Heavy Load ◽  
Micromechanical Properties ◽  
Rough Turning ◽  
Coated Carbide

Tool wear phenomena during the machining of titanium alloys are very complex. Severe adhesive interaction at the tool chip interface, especially at low cutting speeds, leads to intensive Built Up Edge (BUE) formation. Additionally, a high cutting temperature causes rapid wear in the carbide inserts due to the low thermal conductivity of titanium alloys. The current research studies the effect of AlTiN and CrN PVD coatings deposited on cutting tools during the rough turning of a Ti6Al4V alloy with severe BUE formation. Tool wear characteristics were evaluated in detail using a Scanning Electron Microscope (SEM) and volumetric wear measurements. Chip morphology analysis was conducted to assess the in situ tribological performance of the coatings. A high temperature–heavy load tribometer that mimics machining conditions was used to analyze the frictional behavior of the coatings. The micromechanical properties of the coatings were also investigated to gain a better understanding of the coating performance. It was demonstrated that the CrN coating possess unique micromechanical properties and tribological adaptive characteristics that minimize BUE formation and significantly improve tool performance during the machining of the Ti6Al4V alloy.

scholarly journals Biomechanics of insect cuticle: an interdisciplinary experimental challenge

2021 ◽  
Vol 127 (5) ◽  
Author(s):  
Karen Stamm ◽  
Brian Daniel Saltin ◽  
Jan-Henning Dirks
Keyword(s):  
Meta Analysis ◽  
Biomechanical Properties ◽  
Measurement Methods ◽  
Insect Cuticle ◽  
Body Parts ◽  
Scientific Methods ◽  
Advantages And Disadvantages ◽  
Examination Techniques ◽  
Evolutionary Success ◽  
Experimental Challenge

AbstractThe cuticle exoskeleton plays a key role in facilitating the evolutionary success of insects. Since the mid of the last century, many different biomechanical properties of exoskeletons have been investigated, always utilizing the most sophisticated scientific methods available at the time. So far, information on the biomechanical properties of cuticle seems to be as diverse as the methods used to measure them. As a consequence, insect cuticle is often considered to exhibit the most complex and diverse biomechanical properties of any biological material. However, it remains unclear which role the respective measurement methods and sample treatments used in previous studies play in supporting this claim. This review provides a broad overview of examination techniques used to study biomechanical properties of insect exoskeletons and discusses their respective advantages and disadvantages in describing the properties of a complex material such as cuticle. Our meta-analysis of the present data confirms significant effects of the respective measurement methods, sample treatments and body parts on the obtained mechanical properties. Based on our findings, we highlight research gaps and point out important factors which should be taken into account in future studies on insect cuticle.

Bilayer nanocomposite molecular coatings from elastomeric/rigid polymers: fabrication, morphology, and micromechanical properties

2001 ◽  
Vol 167 (1) ◽  
pp. 227-242 ◽  
Author(s):  
Igor Luzinov ◽  
Daungrut Julthongpiput ◽  
Paul D. Bloom ◽  
Valerie V. Sheares ◽  
Vladimir V. Tsukruk
Keyword(s):  
Micromechanical Properties ◽  
Rigid Polymers
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