Ultrafine-grained W alloy prepared by spark plasma sintering with high thermal stability and excellent irradiation resistance

Abstract

Ultrafine-grained W-5wt.% Cr-5wt.% Y (W5C5Y) alloy was prepared by the spark plasma sintering method. Investigation of the microstructure showed that the grain growth was suppressed by the addition of Cr and Y. They not only enhance the density of sintered materials, but also purify and strengthen the grain boundaries through the second-phase particles formed by the reaction with free O. Ultrafine-grained W5C5Y exhibits ultrahigh hardness, which is much higher than that of ITER-grade W. It also shows high thermal stability even at the annealing temperatures of 1000 °C and 1100 °C, and exhibits higher irradiation resistance compared with ITER-grade W.

The Mechanisms of Inhibition Effects on Bubble Growth in He-Irradiated 316L Stainless Steel Fabricated by Selective Laser Melting

“…The interfaces can act as efficient sinks for irradiation-induced defects and promote the annihilation or recombination of the defects. This insight has been systematically demonstrated in nano-particle dispersion-strengthened alloys [24,25], multilayer films [26], multiphase alloys [27], and nanocrystalline alloys [28,29]. By analogy, the unique interfaces between oxide particles and the matrix in SLM 316L would be expected to absorb irradiation-induced defects, thereby suppressing the formation and accumulation of the He bubbles.…”

The Influence of Coherent Oxide Interfaces on the Behaviors of Helium (He) Ion Irradiated ODS W

“…Therefore, developing W-based materials with supreme mechanical properties and high irradiation resistance has been a major goal over the recent decades to meet the requirements of future fusion reactors. For this purpose, numerous strategies have been taken, through solution strengthening [ 3 , 5 ], deformation processing [ 6 , 7 ], grain refining strengthening [ 8 , 9 , 10 ], or dispersion strengthening [ 11 , 12 , 13 ]. Among them, the introduction of nano dispersoids, such as La 2 O 3 , Y 2 O 3 , ZrC, or TiC, in W to form W-based alloys, which are termed as the oxide/carbide dispersion strengthened tungsten materials (ODS/CDS-W), has drawn considerable attentions, and the enhancement of their mechanical properties has been intensively studied.…”

Microhardness and Microstructural Evolution of Pure Nickel Processed by High-Pressure Torsion

“…Therefore, the use of ultrafine-grained (UFG) materials has the potential to produce micro-miniature parts with superior properties. Compared with unprocessed coarse grain (CG) samples, UFG materials generally have more excellent physical properties, mechanical properties, and forming properties [5][6][7][8][9]. For example, its flow stress during deformation at high temperatures should be significantly reduced, and at the same time, there are also excellent applications in the field of superplasticity [10,11].…”