Reactor Neutron and Gamma Irradiation of Various Composite Materials

Materials ◽  
1992 ◽  
pp. 233-239 ◽  
Author(s):  
N. A. Munshi ◽  
H. W. Weber
Keyword(s):  
Composite Materials ◽  
Gamma Irradiation ◽  
Reactor Neutron

Ionizing/Displacement Synergistic Effects in Bipolar Operational Amplifiers Induced by Mixed Reactor Neutron and Gamma Irradiation

2017 ◽  
Author(s):  
Chenhui Wang ◽  
Wei Chen ◽  
Xiaoming Jin ◽  
Yan Liu ◽  
Chao Qi ◽  
...  
Keyword(s):  
Control System ◽  
Gamma Irradiation ◽  
Gamma Rays ◽  
Operational Amplifier ◽  
Nuclear Reactor ◽  
Synergistic Effects ◽  
Operational Amplifiers ◽  
Reactor Neutron ◽  
Reactor Control System ◽  
Nuclear Reactor Control

The bipolar operational amplifier is an important kind of electronic device used in the nuclear reactor control system and its radiation damage threatens the reliability of nuclear operation. In order to explore the degradation of the bipolar operational amplifier induced by reactor neutron and gamma irradiation, radiation experiments were accomplished on particular bipolar operational amplifiers OP07 manufactured by Texas Instruments and Analog Devices. The amplifiers were irradiated in three different environments respectively: individual neutrons, individual gamma rays and mixed irradiation of reactor neutrons and gamma rays simultaneously. The results indicate that for both types of bipolar operational amplifiers, the degradations of the input bias current and the input offset voltage induced by the mixed irradiation of reactor neutrons and gamma rays simultaneously are notably more severe than the simple sum of neutron and gamma degradations measured individually. The mixed irradiation of reactor neutron and gamma rays simultaneously leads to degradation enhancement compared to individual ones and induce ionizing/displacement synergistic effects in the amplifiers. Enough attention should be paid to the degradation enhancement induced by the mixed irradiation for devices may exhibit unexpected failure during reactor operation and accelerate the aging of the nuclear reactor control system.

RADIATION MODIFYING OF COMPOSITE MATERIALS IN CASE OF GAMMA IRRADIATION

2016 ◽  
Vol 1 (12) ◽  
pp. 170-173
Author(s):  
Шешин ◽  
Evgeniy Sheshin ◽  
Денисова ◽  
Lyubov Denisova
Keyword(s):  
Composite Materials ◽  
Gamma Irradiation ◽  
Maximum Concentration ◽  
Polymeric Composite ◽  
Type A ◽  
Polymeric Composites ◽  
Dose Dependence ◽  
Extreme Value ◽  
Radical Reactions ◽  
Kinetics Of

In work researches of mechanisms of radiation oxidation of polymeric composites on the basis of the lead of polystyrene (PS-SS) and polyethylene (PE-SS) filled silikanaty are conducted. In case of gamma irradiation of the filled polymeric composite to growth of an integrated dose there is an increase both concentration of radicals, and content of products of destruction. Depending on an integrated dose and type a polymeric composite also nature of accumulating of radicals changes. So for PS-SS to D = 600 кГр the alkil of R-radical to peroxide of RO2-constitutes the share relation R-/RO2-=2,50 whereas in case of an identical dose increases in PE-SS for RO2 radical (R/RO2=0,83). In case of the maximum concentration of radicals in a reaktoplasts the relation of R/RO2-even more decreases - to 0,67. It is established that in case of rather high values of capacity of a dose extreme value (at most) on dose dependence of change of concentration of macroradicals (R-and RO2-) in the researched composites won´t be shown. The nature of the arising macroradicals like R-and RO2-is closely connected as with kinetics of radical reactions in case of -radiation, and structural and mechanical, diffusive characteristics and type of a polymeric composite.

Comparative Microstructures of Ion Milled and Electrochemically Thinned Composite Materials

1974 ◽  
Vol 32 ◽  
pp. 546-547
Author(s):  
R.R. Russell
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Composite Materials ◽  
Great Difficulty ◽  
Ion Milling ◽  
Transmission Electron ◽  
Ion Damage ◽  
Intermetallic Composite

Transmission electron microscopy of metallic/intermetallic composite materials is most challenging since the microscopist typically has great difficulty preparing specimens with uniform electron thin areas in adjacent phases. The application of ion milling for thinning foils from such materials has been quite effective. Although composite specimens prepared by ion milling have yielded much microstructural information, this technique has some inherent drawbacks such as the possible generation of ion damage near sample surfaces.

Transmission electron microscopy of composite materials

1988 ◽  
Vol 46 ◽  
pp. 1012-1015
Author(s):  
K.P.D. Lagerlof
Keyword(s):  
Composite Materials ◽  
Physical Properties ◽  
Structural Defects ◽  
Structural Composites ◽  
Multiphase Materials ◽  
Structural Reinforcement ◽  
Transmission Electron ◽  
Reinforced Fiber ◽  
Particulate Reinforced Composites ◽  
Definition Of

Although most materials contain more than one phase, and thus are multiphase materials, the definition of composite materials is commonly used to describe those materials containing more than one phase deliberately added to obtain certain desired physical properties. Composite materials are often classified according to their application, i.e. structural composites and electronic composites, but may also be classified according to the type of compounds making up the composite, i.e. metal/ceramic, ceramic/ceramie and metal/semiconductor composites. For structural composites it is also common to refer to the type of structural reinforcement; whisker-reinforced, fiber-reinforced, or particulate reinforced composites [1-4].For all types of composite materials, it is of fundamental importance to understand the relationship between the microstructure and the observed physical properties, and it is therefore vital to properly characterize the microstructure. The interfaces separating the different phases comprising the composite are of particular interest to understand. In structural composites the interface is often the weakest part, where fracture will nucleate, and in electronic composites structural defects at or near the interface will affect the critical electronic properties.

Sign in / Sign up

Export Citation Format

Share Document