Effect of recrystallization on ion-irradiation hardening and microstructural changes in 15Cr-ODS steel

Abstract

The effects of recrystallization on ion-irradiation hardening and microstructural changes were investigated for a 15Cr-ODS ferritic steel. Dual ion-irradiation experiments were performed at 470 °C using 6.4 MeV Fe 3+ ions simultaneously with energy-degraded 1 MeV He + ions. The displacement of damage at 600 nm depth from the specimen surface was 30 dpa. Nano-indentation test with Berkovich type indentation tip was measured by constant stiffness measurement (CSM) technique. Results from nano-indentation tests indicate irradiation hardening in ODS steels even at 470°C, while it wasn't observed in reduced activation ferritic steel. Recrystallized ODS steel shows a larger irradiation hardening, which is considered to be due to the reduction of grain boundaries and interfaces of matrix/oxide particles. In 20 % cold rolled ODS steel after recrystallization, both the hardening and bubble number density were lower than those of recrystallized ODS steel, suggesting that dislocations generated by cold rolling suppress bubble formation. Based on the estimation of irradiation hardening from TEM observation results, it is considered that the bubbles are not the main factor controlling ion-irradiation hardening.

Fast identification method for express end sorting label code based on convolutional recurrent neural network

“…1 Traditional digital recognition methods include template matching [11,12], structural feature [13,14] and support vector machine (SVM) [15,16]. The template matching method is to first establish a template for each character and then use the template to compare with the character to be recognized.…”

Ab Initio Modeling of Y and O Solute Atom Interaction in Small Clusters within the bcc Iron Lattice

“…Interacting with each other, Y and O solutes give rise to various nanoclusters. Along with relatively large ODS particles, these small nanoclusters determine stability of ODS steels . Ab initio modeling of such clusters provides a deep insight into the interactions between impurities in ODS steels …”