Pulsed laser synthesis of carbon-overdoped tungsten with a body-centered orthorhombic structure and planar defects

Abstract

C-overdoped W crystallites with a new body-centered orthorhombic (BCO) structure were synthesized by inward diffusion of C from a substrate upon pulsed laser heating in vacuum. Analytical electron microscopic observations indicated that the BCO-type W has occasional long-range ordering of atoms for the particulates, whereas {110}-shuffling for the nanocondensates tended to form a (111) 30° twist boundary and a (01)/(101) interface with a fair coincidence site lattice upon (hkl)-specific coalescence. The co-existent bcc-W nanocondensates have well-developed ~{110} and ~{112} vicinal surfaces to adjoin as tilt boundaries. The refractory phase assemblages have bimodal UV-visible absorptions for potential machining and optoelectronic/catalytic applications in a harsh environment.