Surface Complexes on Carbon Blacks. I. High Temperature EvacuationStudies

1952 ◽  
Vol 56 (6) ◽  
pp. 753-755 ◽  
Author(s):  
R. B. Anderson ◽  
P. H. Emmett
Keyword(s):  
High Temperature ◽  
Surface Complexes ◽  
Carbon Blacks

The curing retardation and mechanism of high temperature vulcanizing silicone rubber filled with superconductive carbon blacks

2010 ◽  
Vol 51 (1) ◽  
pp. 170-178 ◽  
Author(s):  
Yuanyuan Zhang ◽  
Minglei Pang ◽  
Qiang Xu ◽  
Haifeng Lu ◽  
Jie Zhang ◽  
...  
Keyword(s):  
High Temperature ◽  
Silicone Rubber ◽  
Carbon Blacks

Features of the Reinforcing Action of Carbon Blacks Deduced from the Tear Propagation of Filled Vulcanizates

1961 ◽  
Vol 34 (1) ◽  
pp. 57-65
Author(s):  
A. I. Lukomskaya
Keyword(s):  
High Temperature ◽  
Low Temperature ◽  
Stress Distribution ◽  
Carbon Black ◽  
Natural Rubber ◽  
High Temperatures ◽  
Low Temperatures ◽  
Temperature Range ◽  
Carbon Blacks ◽  
Tear Propagation

Abstract 1. The reinforcing action of carbon blacks is most clearly apparent in the knotty tearing of carbon black rubbers. 2. Knotty tearing is characteristic of rubbers filled with carbon black in definite ranges of deformation and temperature, the position of which depends upon the type of rubber and carbon black. 3. With high contents of contact gas black in vulcanizates of sodium butadiene (SKB) and butadiene sytrene (SKS-30) rubbers two ranges of knotty tearing occur. The first is situated at relatively high temperatures and low rates and the second at relatively low temperatures and higher rates. Reduction in the content of black in these vulcanizates leads to the disappearance of the high temperature range of knotty tearing and the displacement of the low-temperature range towards higher temperatures and low rates. This position of the ranges (at medium rates and temperatures) is characteristic also of the said synthetic rubbers containing thermal black. 4. The first range of knotty tearing of filled SKB and SKS-30 vulcanizates with contact black is linked with the presence in them of carbon black chains, while the second range, existing also with vulcanizates with thermal black, is connected with the presence of carbon black particles. 5. Within the ranges ofr ates from 40 to 1000 mm/min and of temperatures from 40 to +100° C filled vulcanizates of natural rubber have one range of knotty tearing situated at lower rates. In the case of the presence in them of contact gas black the range is shifted towards higher rates than in the case of thermal black. 6. Increasing the length of the nick in testpieces being tested for tear propagation leads to a shift in the range of knotty tearing towards higher rates and widens it with respect to temperatures. This same effect is noted on altering the shape of the testpiece, starting with the Delft testpieces and proceeding to types A, B, and C, i.e. increasing the nonuniformity of stress distribution in the deformed testpieces.

Influence of Thermo-Mechanical Processing on the Microstructure of Beryllia Dispersed Nickel Alloys

1973 ◽  
Vol 31 ◽  
pp. 184-185
Author(s):  
M.S. Grewal ◽  
S.A. Sastri ◽  
N.J. Grant
Keyword(s):  
High Temperature ◽  
Nickel Alloys ◽  
Thermomechanical Processing ◽  
Cold Work ◽  
High Temperature Strength ◽  
Strengthening Effect ◽  
Mechanical Processing ◽  
Uniform Dispersion ◽  
Oxide Particles ◽  
Nickel Base

Currently there is a great interest in developing nickel base alloys with fine and uniform dispersion of stable oxide particles, for high temperature applications. It is well known that the high temperature strength and stability of an oxide dispersed alloy can be greatly improved by appropriate thermomechanical processing, but the mechanism of this strengthening effect is not well understood. This investigation was undertaken to study the dislocation substructures formed in beryllia dispersed nickel alloys as a function of cold work both with and without intermediate anneals. Two alloys, one Ni-lv/oBeo and other Ni-4.5Mo-30Co-2v/oBeo were investigated. The influence of the substructures produced by Thermo-Mechanical Processing (TMP) on the high temperature creep properties of these alloys was also evaluated.

Application of TEM to Deformation, Wear, and Fracture of Ceramics

1974 ◽  
Vol 32 ◽  
pp. 472-473
Author(s):  
B. J. Hockey
Keyword(s):  
Wear Resistance ◽  
High Temperature ◽  
Mechanical Behavior ◽  
Brittle Materials ◽  
High Temperature Strength ◽  
Wide Range ◽  
Corrosive Environments ◽  
Further Development

Ceramics, such as Al2O3 and SiC have numerous current and potential uses in applications where high temperature strength, hardness, and wear resistance are required often in corrosive environments. These materials are, however, highly anisotropic and brittle, so that their mechanical behavior is often unpredictable. The further development of these materials will require a better understanding of the basic mechanisms controlling deformation, wear, and fracture.The purpose of this talk is to describe applications of TEM to the study of the deformation, wear, and fracture of Al2O3. Similar studies are currently being conducted on SiC and the techniques involved should be applicable to a wide range of hard, brittle materials.

Lattice Imaging of Grain Boundaries in Ceramics

1977 ◽  
Vol 35 ◽  
pp. 114-115
Author(s):  
D. R. Clarke ◽  
G. Thomas
Keyword(s):  
Mechanical Properties ◽  
High Temperature ◽  
Silicon Nitride ◽  
Grain Boundaries ◽  
High Temperature Strength ◽  
Current Interest ◽  
Lattice Imaging ◽  
Special Significance ◽  
Structural Applications ◽  
Refractory Ceramics

Grain boundaries have long held a special significance to ceramicists. In part, this has been because it has been impossible until now to actually observe the boundaries themselves. Just as important, however, is the fact that the grain boundaries and their environs have a determing influence on both the mechanisms by which powder compaction occurs during fabrication, and on the overall mechanical properties of the material. One area where the grain boundary plays a particularly important role is in the high temperature strength of hot-pressed ceramics. This is a subject of current interest as extensive efforts are being made to develop ceramics, such as silicon nitride alloys, for high temperature structural applications. In this presentation we describe how the techniques of lattice fringe imaging have made it possible to study the grain boundaries in a number of refractory ceramics, and illustrate some of the findings.

Effect of Improved ThO2 Particle Dispersion in Nickel on High-Temperature Strength

1970 ◽  
Vol 28 ◽  
pp. 444-445
Author(s):  
E. R. Kimmel ◽  
H. L. Anthony ◽  
W. Scheithauer
Keyword(s):  
High Temperature ◽  
Metal Matrix ◽  
Oxide Particle ◽  
Oxide Phase ◽  
Dislocation Motion ◽  
Particle Dispersion ◽  
High Temperature Strength ◽  
Strengthening Effect ◽  
Oxide Particles ◽  
The Stability

The strengthening effect at high temperature produced by a dispersed oxide phase in a metal matrix is seemingly dependent on at least two major contributors: oxide particle size and spatial distribution, and stability of the worked microstructure. These two are strongly interrelated. The stability of the microstructure is produced by polygonization of the worked structure forming low angle cell boundaries which become anchored by the dispersed oxide particles. The effect of the particles on strength is therefore twofold, in that they stabilize the worked microstructure and also hinder dislocation motion during loading.

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