Thermal expansion of a composite with a hybrid granular-fibrous filler

1989 ◽  
Vol 25 (2) ◽  
pp. 173-182 ◽  
Author(s):  
Yu. A. Dzenis
Author(s):  
J. Cooper ◽  
O. Popoola ◽  
W. M. Kriven

Nickel sulfide inclusions have been implicated in the spontaneous fracture of large windows of tempered plate glass. Two alternative explanations for the fracture-initiating behaviour of these inclusions have been proposed: (1) the volume increase which accompanies the α to β phase transformation in stoichiometric NiS, and (2) the thermal expansion mismatch between the nickel sulfide phases and the glass matrix. The microstructure and microchemistry of the small inclusions (80 to 250 μm spheres), needed to determine the cause of fracture, have not been well characterized hitherto. The aim of this communication is to report a detailed TEM and EDS study of the inclusions.


1995 ◽  
Vol 05 (C8) ◽  
pp. C8-1109-C8-1113
Author(s):  
T.R. Finlayson, ◽  
M. Liu ◽  
T.F. Smith
Keyword(s):  

1978 ◽  
Vol 39 (C6) ◽  
pp. C6-406-C6-407 ◽  
Author(s):  
T. Fukase ◽  
T. Kobayashi ◽  
M. Isino ◽  
N. Toyota ◽  
Y. Muto

1980 ◽  
Vol 41 (C8) ◽  
pp. C8-875-C8-877
Author(s):  
E. Girt ◽  
P. Tomić ◽  
A. Kuršumović ◽  
T. Mihać-Kosanović

1988 ◽  
Vol 49 (C8) ◽  
pp. C8-1903-C8-1904
Author(s):  
S. U. Jen ◽  
Y. D. Yao ◽  
H. Y. Pai

1988 ◽  
Vol 49 (C8) ◽  
pp. C8-159-C8-160
Author(s):  
T. Suzuki ◽  
T. Kanomata ◽  
T. Kaneko

The article presents the study of processes of structure formation of cement stone and products of hardening of organic-mineral compositions with fibrous filler (shavings) by the electronic scanning microscopy method. It is established that the additive-free cement stone at the age of 28 days has a dense and homogeneous structure, consists of calcium hydro-silicates, Portlandite and calcite - newgrowths characteristic for cement systems. Cellulose fibers, which make up the bulk of the substance of shavings, are sufficiently active, which determines the high adhesion of the hydration products of the cement binder to their surface. It is shown that the introduction of shavings into the organo-mineral composition leads to inhibition of cement hydration processes. Organo-mineral compositions with different shavings content (two compositions) were analyzed. The first composition is characterized by a fairly dense structure, the cement stone consists of globular nanoscale nuclei of hydrosilicates, Portlandite and calcite. The second composition has a loose porous structure, cement stone consists of non-hydrated cement grains, newgrowths are represented by calcite and vaterite. The structure of the contact zone "osprey fiber-cement stone" in the organo-mineral composition of the first composition indicates a good adhesion of the filler surface with the phases of hydrated cement. The use of shavings as a fibrous filler (the first composition) increases the tensile and bending strength, as well as the wear resistance of organo-mineral compositions. The data obtained by scanning electron microscopy are confirmed by the results of studying the processes of structure formation of cement stone by quantitative x-ray phase analysis.


1981 ◽  
Vol 6 ◽  
Author(s):  
J.R. Mclaren ◽  
R.W. Davidge ◽  
I. Titchell ◽  
K. Sincock ◽  
A. Bromley

ABSTRACTHeating to temperatures up to 500°C, gives a reduction in Young's modulus and increase in permeability of granitic rocks and it is likely that a major reason is grain boundary cracking. The cracking of grain boundary facets in polycrystalline multiphase materials showing anisotropic thermal expansion behaviour is controlled by several microstructural factors in addition to the intrinsic thermal and elastic properties. Of specific interest are the relative orientations of the two grains meeting at the facet, and the size of the facet; these factors thus introduce two statistical aspects to the problem and these are introduced to give quantitative data on crack density versus temperature. The theory is compared with experimental measurements of Young's modulus and permeability for various rocks as a function of temperature. There is good qualitative agreement, and the additional (mainly microstructural) data required for a quantitative comparison are defined.


Sign in / Sign up

Export Citation Format

Share Document