THE ADDITIONAL PROPERTIES IN DEFECT CONTROLLED CERAMICS

陶瓷材料(AlN、BN)具有高熔点、高导热系数和极高硬度等特点，是用于聚变反应堆和高温环境下能量转换的主要候选材料之一。本实验的目的是研究氮化物中缺陷的产生与力学性能变化之间的关系。用光学a吸附和ESR方法研究了反应堆(KUR)中子引起的产点缺陷和烧结AIN和c-BN中缺陷的热行为，并进一步估计了辐照后氮化物的硬度提高。1.用2.8×10^&lt；15&gt；-5.3×10^&lt；16&gt；n/cm^2(快中子：E&GT；0.1 MeV)，在25K下，快中子轰击和释放的高能的不清晰反应产生氮化物中的各种类型的缺陷。与ESR信号相对应的缺陷被指定为电子捕获的氮空位。2.用等向法研究了这些氮化物在中子辐照后的硬化。尤其是c-BN的硬度随中子剂量的增加而明显增加。

The ceramics(AIN,BN)possess a various interesting characterestics, such as,high melting point,very high thermal conductivity and extreme hardness.It is one of the primary candidate materials for use in fusion reactor and conversion of energy at elevated temperature environments. It is the purpose of this experiment to investigate the relation between the defect production and the change of mechanical properties in the nitrides.The production point defects induced by reactor(KUR) neutron and the thermal behavior of the defect in sintered AIN and c-BN were studied using optical a sorption and ESR methods.Further,the enhancement of hardness in irradiated nitrides were also estimated.1.The specimens were irradiated by neutrons in the range of 2.8 x 10^<15> - 5.3 x 10^<16>n/cm^2(fast neutron:E>0.1 MeV) at 25 K.Fast neutron bombardment and the unclear reactions ^<10>B and ^<14>N with released high energy produce the various type of defects in the nitrides. The defect corresponding the ESR signal in assigned to be an electron trapped nitrogen vacancy. 2.Hardening after neutron irradiation was also studied in these nitrides using the identation method. In especially,hardness in c-BN increased clearly with neutron dose.