Oxidative and Nonoxidative Thermal Degradation of Rubber

1956 ◽  
Vol 29 (3) ◽  
pp. 857-879 ◽  
Author(s):  
G. J. van Amerongen
Keyword(s):  
Mechanical Properties ◽  
Thermal Decomposition ◽  
High Temperature ◽  
Thermal Degradation ◽  
High Resistance ◽  
Marked Change ◽  
Vulcanized Rubber ◽  
Resistance To Oxidation ◽  
Thermal Deterioration ◽  
Short Time

Abstract The mechanical properties of rubber often undergo a marked change on heating, with deterioration of its elasticity and strength as a result. This behavior is a problem not merely where rubber is used in surroundings of prevailing high temperature; arguments can be advanced to show that thermal deterioration may influence to some extent as seemingly remote a property as wear. The behavior of rubber exposed to heat is strongly influenced by the presence or absence of oxygen. When an ordinary rubber vulcanizate is heated to, say, 100° C in the presence of oxygen or air, it undergoes substantial changes in a comparatively short time. Yet the effects may be similar in the absence of oxygen at temperatures 60° to 100° C higher. The inference is that, although a given rubber heated in air to 100° C, for instance, may be stable owing to its high resistance to oxidation, it may become completely unstable when heated to 180° C on account of thermal decomposition. This paper is published to provide fuller details of the behavior of rubber when heated in the presence and absence of oxygen. The evidence was obtained from experiments with both unvulcanized and vulcanized rubber, differing in composition.

HASTELLOY ALLOY S

Alloy Digest ◽  
1973 ◽  
Vol 22 (1) ◽  
Keyword(s):  
Mechanical Properties ◽  
High Temperature ◽  
Heat Treating ◽  
High Temperature Alloy ◽  
Excellent Thermal Stability ◽  
Cabot Corporation ◽  
High Temperature Mechanical Properties ◽  
Temperature Performance ◽  
Resistance To Oxidation ◽  
Nickel Base

Abstract HASTELLOY alloy S is a nickel-base high-temperature alloy having excellent thermal stability, good high-temperature mechanical properties and excellent resistance to oxidation up to 2000 F. This datasheet provides information on composition, physical properties, elasticity, and tensile properties as well as creep. It also includes information on high temperature performance and corrosion resistance as well as forming, heat treating, machining, and joining. Filing Code: Ni-184. Producer or source: Stellite Division, Cabot Corporation.

scholarly journals High Temperature Degradation Mechanism of Concrete with Plastering Layer

Materials ◽  
2022 ◽  
Vol 15 (2) ◽  
pp. 398
Author(s):  
Chihao Liu ◽  
Jiajian Chen
Keyword(s):  
Mechanical Properties ◽  
Mechanical Property ◽  
Thermal Decomposition ◽  
Electron Microscope ◽  
High Temperature ◽  
Thermogravimetric Analysis ◽  
Degradation Mechanism ◽  
Cement Ratio ◽  
Water Cement Ratio ◽  
Scanning Electron

At present, the research on the high temperature degradation of concrete usually focuses on only the degradation of concrete itself without considering the effect of the plastering layer. It is necessary to take into account the influence of the plastering layer on the high temperature degradation of concrete. With an increase in the water/cement ratio, the explosion of concrete disappeared. Although increasing the water/cement ratio can alleviate the cracking of concrete due to lower pressure, it leads to a decrease in the mechanical properties of concrete after heating. It is proved that besides the water/cement ratio, the apparent phenomena and mechanical properties of concrete at high temperature can be affected by the plastering layer. The plastering layer can relieve the high temperature cracking of concrete, and even inhibit the high temperature explosion of concrete with 0.30 water/cement ratio. By means of an XRD test, scanning electron microscope test and thermogravimetric analysis, it is found that the plastering layer can promote the rehydration of unhydrated cement particles of 0.30 water/cement ratio concrete at high temperature and then promote the mechanical properties of concrete at 400 °C. However, the plastering layer accelerated the thermal decomposition of C-S-H gel of concrete with a water/cement ratio of 0.40 at high temperature, and finally accelerate the decline of mechanical property of concrete. To conclude, the low water/cement ratio and plastering layer can delay the deterioration of concrete at high temperature.

A Novel Method to Recycle Scrap Tires: High-Pressure High-Temperature Sintering

2002 ◽  
Vol 75 (5) ◽  
pp. 955-968 ◽  
Author(s):  
Jeremy E. Morin ◽  
Drew E. Williams ◽  
Richard J. Farris
Keyword(s):  
Mechanical Properties ◽  
High Pressure ◽  
High Temperature ◽  
Rubber Particle ◽  
Styrene Butadiene Rubber ◽  
Butadiene Rubber ◽  
Scrap Tires ◽  
Vulcanized Rubber ◽  
High Pressure High Temperature ◽  
Styrene Butadiene

Abstract High-pressure high-temperature sintering (HPHTS) is a novel recycling technique that makes it possible to recycle vulcanized rubber powders made from waste rubber (namely scrap tires) through only the application of heat and pressure. A brief look into the mechanism of sintering will be presented along with information about the influence of molding variables, such as time, temperature, pressure and rubber particle size on the mechanical properties of the produced parts. One of the most interesting observations is that powders of every crosslinked elastomer attempted sintered together via this technique, including silicone rubber (SI), sulfur cured [natural rubber (NR), ethylene-propylene-diene rubber (EPDM), styrene-butadiene rubber (SBR)], peroxide cured butadiene rubber (BR), and fluoroelastomers (FKM). Early work on sintered rubber made from commercially available rubber powder had a modulus of 1 to 2 MPa, strength of 4 to 7 MPa and an elongation at break of 150–250%. Recently, in-house ground samples of SBR have had sintered values over 9.5 MPa strength and 275% elongation, or greater than 60% retention of the original properties. Many of these mechanical properties are comparable with industrially manufactured rubbers, and it is believed that recycled rubbers produced via HPHTS offer the potential to replace virgin rubber in numerous applications.

SICROMO 2

Alloy Digest ◽  
1956 ◽  
Vol 5 (1) ◽  
Keyword(s):  
Fracture Toughness ◽  
Corrosion Resistance ◽  
High Temperature ◽  
Physical Properties ◽  
High Resistance ◽  
Roller Bearing ◽  
Low Carbon ◽  
Temperature Performance ◽  
Resistance To Oxidation ◽  
Molybdenum Steel

Abstract SICROMO-2 is a low-carbon, silicon-chromium-molybdenum steel recommended for those applications at temperatures up to 1200 F. in which a high resistance to oxidation is required. This datasheet provides information on composition, physical properties, elasticity, and tensile properties as well as fracture toughness and creep. It also includes information on high temperature performance and corrosion resistance as well as forming, machining, and joining. Filing Code: SA-36. Producer or source: Timken Roller Bearing Company.

ACI TYPE HF

Alloy Digest ◽  
1963 ◽  
Vol 12 (5) ◽  
Keyword(s):  
Stainless Steel ◽  
Corrosion Resistance ◽  
High Temperature ◽  
High Resistance ◽  
Elevated Temperatures ◽  
High Strength ◽  
Heat Treating ◽  
Temperature Performance ◽  
Resistance To Oxidation ◽  
Iron Chromium

Abstract Type HF is an austenitic iron-chromium-nickel alloy offering high resistance to oxidation at elevated temperatures, high strength and corrosion resistance. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties as well as creep. It also includes information on high temperature performance and corrosion resistance as well as casting, heat treating, machining, and joining. Filing Code: SS-143. Producer or source: Stainless steel foundries.

scholarly journals Mechanical Degradation and Thermal Decomposition of Ethylene-Vinyl Acetate (EVA) Polymer-Modified Cement Mortar (PCM) Exposed to High-Temperature

2019 ◽  
Vol 11 (2) ◽  
pp. 500 ◽  
Author(s):  
Hyung-Jun Kim ◽  
Jae-Yeon Park ◽  
Heong-Won Suh ◽  
Beom-Yeon Cho ◽  
Won-Jun Park ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Thermal Decomposition ◽  
Compressive Strength ◽  
High Temperature ◽  
Vinyl Acetate ◽  
Cement Mortar ◽  
Ethylene Vinyl Acetate ◽  
Mechanical Degradation ◽  
Rc Structures ◽  
Cement Ratio

A polymer-modified cement mortar (PCM) is widely used as a repair material for reinforced concrete (RC) structures owing to its excellent strength and durability. However, considering the maintenance of the RC structures and the use period of the structures, the change in the physical properties of the PCM should be evaluated when exposed to various high-temperature environments, such as fires. In this study, the degradation of the mechanical properties (compressive strength and modulus of elasticity), thermal decomposition of the PCM in various high-temperature environments, and the change in the pore structure of the PCM after exposure to high temperatures were quantitatively investigated. A mechanical property evaluation of PCM was performed under three heating conditions: (i) heating in a compression tester, (ii) heating the specimen in an oven to a predetermined temperature and then moving it to a compression tester preheated to the same temperature, and (iii) cooling to room temperature after heating. In the experiment, a PCM specimen was prepared by changing the polymer–cement ratio (polymer content) of ethylene-vinyl acetate (EVA), the most commonly used polymer, to perform a high-temperature sectional test from 200 to 800 °C. In addition, to investigate the change in the PCM mechanical properties in the high-temperature region, in terms of the pyrolysis of EVA, the porosity change and mass change were examined using thermal analysis and mercury intrusion porosimetry. Before heating, the compressive strength of the PCM increased with the EVA content up to 10 % of the polymer–cement ratio. Under the cooling conditions after heating up to 200 °C, the mechanical performance of the PCM was restored, whereas the degradation of the mechanical properties of the PCM without cooling was more pronounced. Furthermore, the mass loss, heat flow, and the total porosity of the PCM increased as the EVA content increased, which is correlated with the degradation of the mechanical properties of the PCM.

FANSTEEL 82

Alloy Digest ◽  
1963 ◽  
Vol 12 (2) ◽  
Keyword(s):  
High Temperature ◽  
Physical Properties ◽  
Surface Treatment ◽  
Protective Coating ◽  
Base Alloy ◽  
Heat Treating ◽  
High Temperature Strength ◽  
Temperature Performance ◽  
Resistance To Oxidation ◽  
Short Time

Abstract Fansteel 82 is a columbium base alloy having superior high temperature strength while retaining the good fabricability of pure columbium. Fansteel 82 exhibits superior resistance to oxidation at temperatures above 1800 F; however, a protective coating will be necessary except for only very short time applications. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties as well as creep. It also includes information on high temperature performance as well as forming, heat treating, machining, joining, and surface treatment. Filing Code: Cb-3. Producer or source: Fansteel Metallurgical Corporation.

Brazing of Ti Using a Zr-Based Amorphous Filler

2008 ◽  
Vol 135 ◽  
pp. 131-134 ◽  
Author(s):  
Jung G. Lee ◽  
Jong Keuk Lee ◽  
Min Ku Lee ◽  
Deog Nam Shim ◽  
Chang Kyu Rhee
Keyword(s):  
Mechanical Properties ◽  
High Temperature ◽  
Liquid Region ◽  
Residual Liquid ◽  
Base Metals ◽  
Acicular Structure ◽  
Homogeneous Composition ◽  
Short Time ◽  
Temperature Heating ◽  
High Temperature Heating

The microstructure and mechanical properties of Ti joints brazed with a Zr41.2Ti13.8Ni10.0Cu12.5Be22.5 (at.%) amorphous filler were investigated. With a Zr-based amorphous filler, in this study, Ti joints with a homogeneous composition could be obtained by heating to well below the α-β transformation temperature for a short time, so that the undesirable effects of the high temperature heating are considerably diminished. The joints brazed at 790 °C for 10 min consisted of the coarse acicular structure rather than the fine Widmanstätten structure which generally deteriorates the ductility of the joints. The joints with the homogenous coarse acicular structure, i.e. without a residual liquid region, show almost the same mechanical properties as those required for base metals without heating. Although the residual liquid region in the joints deteriorates the ductility of the joints, this region could be successfully removed by a diminution in the quantity of the filler.

scholarly journals THE INFLUENCE OF SHORT TIME WATER COOLING ON THE MECHANICAL PROPERTIES OF CONCRETE HEATED UP TO HIGH TEMPERATURE

2005 ◽  
Vol 11 (2) ◽  
pp. 85-90
Author(s):  
Marian Abramowicz ◽  
Robert Kowalski
Keyword(s):  
Mechanical Properties ◽  
Compressive Strength ◽  
High Temperature ◽  
Electric Furnace ◽  
Water Cooling ◽  
Test Results ◽  
Compressive Strength Of Concrete ◽  
Short Time

This paper deals with the description of tests on concrete subjected to a high temperature and then cooled in two ways. Two series of cylinder specimens (103 mm in diameter, 200 mm in height) made of concrete C25/30 and C40/50 were tested. Specimens were heated in the electric furnace to 270, 370 and 500 °C. After heating, some of specimens were left in the open air and some of them were put in water for 10 sec and then left in the open air. Next day the compressive strength of concrete was tested. Test results are presented. In addition, the paper includes some test results taken from the literature.

Sign in / Sign up

Export Citation Format

Share Document