In advanced nuclear reactors,helium can inevitably be produced via(n,)reaction and may precipitate into nano-scale helium bubbles in materials,and can causes degradation of material properties.In the present study,eff...In advanced nuclear reactors,helium can inevitably be produced via(n,)reaction and may precipitate into nano-scale helium bubbles in materials,and can causes degradation of material properties.In the present study,effects of helium bubbles formation in an oxide dispersion strengthened(ODS)steel is studied.Specimens of an ODS ferritic steel(15Cr-4Al-0.6Zr-0.1Ti)were implanted with mutiple-energy He ions at room temperature at the terminal of the 320 kV High-voltage Platform in IMP,to create a damage plateau of 0.4 dpa for average(corresponding to an He concentration of about 7000 appm)from the near surface to a depth about 1m.The specimen was subsequently thermally annealed at 800℃for 1 h in vacuum so that simple defects formed in the as-implanted state underwent significant recombination,meanwhile helium bubbles at nano-scale were formed.展开更多
Silicon carbide(SiC)fiber possesses low neutron capture cross-section,low induced radioactivity,high thermal stability,low density,high specific strength,good oxidation-ablation resistance,high specific modulus,especi...Silicon carbide(SiC)fiber possesses low neutron capture cross-section,low induced radioactivity,high thermal stability,low density,high specific strength,good oxidation-ablation resistance,high specific modulus,especially improved flaw tolerance and non-catastrophic mode of failure.Therefore,silicon carbide fiber is considered as a candidate structural component in advanced nuclear industry fields.The irradiation damage which silicon carbide fiber will be subject to is inevitable.For structural components in fast breed reactors or in fusion reactors,the energy of PKAs(primary knocked-on atoms)produced by high-energy neutron irradiation can be several hundred keV,therefore effects of energy deposition via electronic processes(excitation and ionization)by PKAs in materials cannot be ignored.In situations of fuel cladding,materials may surfer from irradiation by fission fragments(which are heavy ions with up to hundreds of MeV).It is therefore necessary to know effects of energetic heavy-ion irradiation in silicon carbide for nuclear application.展开更多
文摘In advanced nuclear reactors,helium can inevitably be produced via(n,)reaction and may precipitate into nano-scale helium bubbles in materials,and can causes degradation of material properties.In the present study,effects of helium bubbles formation in an oxide dispersion strengthened(ODS)steel is studied.Specimens of an ODS ferritic steel(15Cr-4Al-0.6Zr-0.1Ti)were implanted with mutiple-energy He ions at room temperature at the terminal of the 320 kV High-voltage Platform in IMP,to create a damage plateau of 0.4 dpa for average(corresponding to an He concentration of about 7000 appm)from the near surface to a depth about 1m.The specimen was subsequently thermally annealed at 800℃for 1 h in vacuum so that simple defects formed in the as-implanted state underwent significant recombination,meanwhile helium bubbles at nano-scale were formed.
文摘Silicon carbide(SiC)fiber possesses low neutron capture cross-section,low induced radioactivity,high thermal stability,low density,high specific strength,good oxidation-ablation resistance,high specific modulus,especially improved flaw tolerance and non-catastrophic mode of failure.Therefore,silicon carbide fiber is considered as a candidate structural component in advanced nuclear industry fields.The irradiation damage which silicon carbide fiber will be subject to is inevitable.For structural components in fast breed reactors or in fusion reactors,the energy of PKAs(primary knocked-on atoms)produced by high-energy neutron irradiation can be several hundred keV,therefore effects of energy deposition via electronic processes(excitation and ionization)by PKAs in materials cannot be ignored.In situations of fuel cladding,materials may surfer from irradiation by fission fragments(which are heavy ions with up to hundreds of MeV).It is therefore necessary to know effects of energetic heavy-ion irradiation in silicon carbide for nuclear application.
