载能离子辐照的ODS铁素体钢硬化效应的研究

Irradiation Hardening of High-Cr ODS Ferritic Steels Under Helium Implantation and Heavy-ion Irradiation

研究了氧化物弥散强化(ODS)的3种铁素体钢,包括:19Cr-3.5AlODS钢(MA956),16Cr-0.1TiODS和16Cr-0.1ZrODS铁素体钢,在多能量的氦离子和MeV能量级的Bi、Xe离子辐照条件下的硬化效应。获得了辐照硬化与原子离位损伤水平(dpa)、He注入浓度的关系。结果表明,材料的硬度在低剂量范围会随着辐照剂量迅速增加,而在高剂量范围材料的硬度逐渐趋于饱和,可以用1/2次的幂函数拟合辐照硬化与离位损伤水平之间的关系。不同入射离子——Bi离子和Xe离子都会引起ODS钢的硬化,而氦离子还会在材料中聚集导致氦泡的形成,造成更加明显的硬化。实验证明,Ti或Zr掺杂的16Cr-ODS铁素体钢较19Cr-3.5AlODS钢具有更强的抗辐照硬化能力,原因可归于其含有更高数密度的细小氧化物粒子——能够有效俘获点缺陷和氦原子,从而有效抑制晶粒内部和晶界出缺陷的长大。

The present work investigates the irradiation hardening of ODS ferritic steels after multi-energy He-ion implantation, or energetic Bi-ion and Xe-ion irradiation, to get an understanding of dependence of irradiation-hardening on atomic displacement damage and gas accumulation. Three kinds of high-Cr ODS ferritic steels including the commercial MA956 (19Cr-3.5Al), the 16Cr-0.1Ti and the 16Cr-0.1Zr ODS ferritic steels were used. The results show that the hardness increases rapidly at the lower doses but tends to saturate at the higher dose. An 1/2-power law dependence on dpa value is obtained. Helium implantation contributes significantly to the irradiation hardening, possibly due to the impediment of the motion dislocations by helium bubbles. 16Cr-ODS (Ti or Zr added) ferritic which contains finer oxide particles in higher number density shows higher resistance to irradiation hardening than the MA056.