جستجوی مقالات مرتبط با کلیدواژه « boron carbide » در نشریات گروه « فیزیک »

The present study investigated the structural, mechanical, and nuclear properties of two types of polymeric and metallic composites containing boron carbide particles. The neutron transmission test obtained lower neutron transmission in BPAER reinforced with B4C nanoparticles compared to the microparticle-reinforced composite. The stress-strain diagrams obtained from the tensile test show the improvement of the mechanical properties of the epoxy resin composite reinforced with B4C nanoparticles compared to the microparticles. The neutron transmission test also indicates an improvement in the nuclear properties of the Al-B4C nanocomposite compared to the Al-B4C micro composite. On the other hand, the density of this nanocomposite shows an increase compared to the micro composite. Also, regardless of the size and amount of carbide particles added, the density of all composite samples was lower than that of aluminum. Also, the hardness of the composite increased with increasing the amount of reinforcing phase, which was more in the nanocomposite samples than in the micro composite samples.

The use of metal matrix composites can provide a combination of desirable properties of metals as well as the special physical properties of neutron absorber reinforcing particles such as boron carbide, which alone may be brittle. Therefore, in the present study on neutron attenuation power of composite shielding, several Al-B4C composite samples with weight fractions of 5, 10 and 20% B4C have been used. In order to investigate the neutron absorption properties of the studied samples, the MCNP Monte Carlo code and the neutron source of the dry channel of the MNSR reactor with a flux of 2.13E+5 n.cm-2.s-1 have been used  ,which provided in nominal reactor power of 30 kW. The results show that the neutron flux in the presence of 5, 10 and 20% boron carbide samples is predicted to be 1.32E+05 n.cm-2.s-1,1.12E+05 n.cm-2.s-1 and 1.07E+05 n.cm-2.s-1, respectively. With this increase in the percentage of reinforcement phase, neutron flux is reduced down to 50%.