He+ 辐照对CLAM钢焊缝微观组织和性能的影响

在室温下用强度为70 keV的He⁺辐照CLAM钢焊缝,使用扫描电子显微镜(SEM)、透射电子显微镜(TEM)和连续刚度纳米压痕技术(CSM)对其表征,研究了He⁺辐照对CLAM钢焊缝的微观组织和性能的影响。结果表明,随辐照剂量的增大焊缝表面黑色孔洞的尺寸增大、密度提高；辐照剂量为1×10¹⁷ ions·cm^-2时,在两种焊缝中形成的位错环的尺寸分别约为18.97 nm、15.73 nm,数密度分别约为2.24×10²¹ m^-3、1.78×10²¹ m^-3,氦泡引起的辐照肿胀率分别约为1.7%和0.4%；辐照缺陷(位错环、氦泡)导致的辐照硬化率分别为49.0%和29.9%。与焊态焊缝相比,调质处理态焊缝的辐照损伤较弱,在一定程度上表明经调质处理后焊缝的抗辐照性能有所提高。

Effect of He Ion Irradiation on Microstructure and Properties of CLAM Steel Weld

In order to explore the mechanism of the influence of ion irradiation on the microstructure and properties of as-welded and quenched and tempered welds, the welds of Low Activation Martensitic (CLAM) steel were subjected to He ion irradiation at room temperature of 70 keV. Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM) and Continuous Stiffness Measurement (CSM) detection methods were utilized to investigate the changes in microstructure and properties of CLAM steel welds before and after ion irradiation. The results show that the size and number density of black holes on the welds' surface after irradiation increased with the rising irradiation dose; at the irradiation dose of 1×10¹⁷ ions·cm^-2, the sizes of dislocation loops formed in the two welds were 18.97 nm and 15.73 nm respectively and the number densities were 2.24×10²¹ m^-3 and 1.78×10²¹ m^-3 respectively; the irradiation swelling rates caused by helium bubbles were 1.7% and 0.4% respectively; the radiation hardening rate caused by irradiation defects (dislocation loops and helium bubbles) were 49.0% and 29.9%, respectively. However, compared with as-welded weld, the irradiation damage of quenched and tempered weld was relatively weaker after He ion irradiation. To a certain extent, it showed that the anti-irradiation performance of the weld after quenched and tempered was improved.