Results 301 to 310 of about 44,589 (331)

Elastic recovery at hardness indentations

Journal of Materials Science, 1981
The mechanics of hardness indentation are considered. On the basis of a cycle in which the loading is elastic-plastic and the unloading (and subsequent reloading) elastic, an expression is derived for the relative depth recovery of the impression as a function of hardness/modulus,H/E. Experimental observations on indented surfaces of selected materials,
V. R. Howes, Brian R. Lawn
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Indentation Hardness of Diamond [PDF]

Nature, 1956
RECENTLY, S. Tolansky and V. R. Howes1 published some data on indentation compression strength with a diamond ball (0.39 mm. radius) on differently orientated diamond faces. They obtained values for the pressure which caused cracking on different diamond faces ranging from 1.2 to 1.8 × 1011 dyne-cm.−2 (1,200–1,800 kgm./mm.2).
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Calculation of Indentation Hardness Based on Indentation Energy

Advanced Materials Research, 2011
Comparing advantages and disadvantages of Oliver-Pharr method, microhardness method and indentation energy method, this article propses the improvement of indentation energy method. The improvement of indentation energy method mainly takes the calculation of energy and pile-up and sink-in phenomenon into account.
G.Q. Pan, Zhi Rong Liao, Yong Ze Guo, X.R. Liang, Li Zhou   +4 more
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On two indentation hardness definitions

Surface and Coatings Technology, 2002
The difference between the contact area under load and the residual projected area of an indentation after complete unloading has been studied for various materials using finite element and dimensional analyses of cone indentation. The difference in the contact areas gives rise to two hardness values, one based on the contact area under load and ...
Zhiyong Li, Yang-Tse Cheng, Srinivasan Chandrasekar, Henry T. Yang   +3 more
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The indentation behaviour of hard metals

Journal of Physics D: Applied Physics, 1976
The indentation behaviour of hard materials which deform plastically and also exhibit surface fracture is discussed. It is shown that both radial and circumferential fracture can develop around the indentation and that this can be explained in terms of a transition from elastic/plastic behaviour.
J E Field, C J Studman
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Indentation hardness of biomorphic SiC

International Journal of Refractory Metals and Hard Materials, 2005
Vickers hardness (HV) measurements have been performed in SiC samples fabricated from various wood precursors (pine, beech, and eucalyptus): bioSiC. It was found that hardness was highly dependent on starting wood structure. The arrangement of wood cells determined the final microstructure of the bioSiC (pores distribution and SiC/Si ratio).
F. Gutierrez-Mora, F. Gutierrez-Mora, J. Martínez Fernández, F. M. Varela-Feria, K.C. Goretta, A.R. Arellano López   +5 more
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Topics in indentation hardness

Metal Science, 1982
Problemes recents au sujet de la mesure de durete par indentation: comparaison de corps solides par indentation mutuelle, indentation de solides de faible module d'elasticite et de grande limite elastique, anisotropie de la durete, rupture par identation, durete et restauration elasticique, effets d ...
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Dynamic Indentation Hardness of Metals [PDF]

, 2006
An experimental technique for determining the dynamic indentation hardness of materials is described. Unlike the traditional static hardness measurements, the dynamic hardness measurements can capture the inherent rate dependent material response that is germane to high strain rate deformation processes such as high speed machining and impact.
Ghatu Subhash, Brian J. Koeppel
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A pentagonal indenter for hardness measurements

Journal of Physics E: Scientific Instruments, 1975
A new indenter has been designed to eliminate the anisotropy normally observed in hardness measurements on single crystals when the Vickers, Berkovich and Knoop indenters are used. It has the form of a regular pentagon based pyramid with an angle of 65 degrees between each facet face and its geometric axis.
B Moxley, C A Brookes
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Indentation hardness and hot pressing

Acta Metallurgica, 1980
Methods are reviewed for calculating the pressure distribution over the area of contact between spheres undergoing linear deformation. The relationship P[p(r,t)] = (4/πR)Q[(a2 − r2)12], where p is the pressure over the interface. R is the sphere radius, a is the radius of the circle of contact and r is the polar co-ordinate in the interface, holds when
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