Ultrahigh transverse rupture strength in tungsten-based nanocomposites with minimal lattice misfit and dual microstructure

Chakravarty, D and Laxman, N and Jayasree, R and Mane, RB and Mathiazhagan, S and Srinivas, PVV and Das, R and Nagini, M and Eizadjou, M and Venkatesh, L and Ravi, N and Mahapatra, DR and Vijay, R and Ringer, SP and Tiwary, CS (2021) Ultrahigh transverse rupture strength in tungsten-based nanocomposites with minimal lattice misfit and dual microstructure. In: International Journal of Refractory Metals and Hard Materials, 95 .

	PDF Int-Jou-Ref-MaT.pdf - Published Version Restricted to Registered users only Download (4MB) | Request a copy
	Video (MP4) 1-s2.0-S0263436820303309-mmc1.mp4 - Published Version Restricted to Registered users only Download (2MB) | Request a copy

Abstract

New-generation structural materials with superior properties are a constant demand in applications involving extreme environments. Here, we demonstrate the fabrication of a high-strength, high-dense W-TaC-Ta2O5 nanocomposite for such applications on a large scale by a simple, cost-effective, scalable, bottom-up powder metallurgy approach using plasma sintering. The first clear microstructural evidence of the scavenging effect of carbide particles in the W-MC composites (M = Ta, Zr, Hf, Ti) is demonstrated through atom probe studies. Localized plastic deformation and the unique stress-induced amorphization in tungsten are observed due to dislocation activities, and these phenomena are corroborated by molecular dynamics (MD) simulations. Optimized composition and processing conditions yield high Vickers hardness ~540 HV10 and super-high transverse rupture strength (TRS) ~ 1650 MPa, in upscaled components of 100 mm diameter. The enhanced mechanical properties are attributed to the cumulative effect of the grain boundary strengthening and dispersion strengthening from the refined tungsten grains and the second phase intragranular nanocrystalline particles, respectively, the coherent particle-matrix interfaces, the low oxygen-segregation at grain boundaries and the �dual nanocrystalline-amorphous� microstructure present in the matrix. © 2020 Elsevier Ltd

Item Type:	Journal Article
Publication:	International Journal of Refractory Metals and Hard Materials
Publisher:	Elsevier Ltd
Additional Information:	Copyright to this article belongs to Elsevier Ltd
Keywords:	Carbides; Cost effectiveness; Grain boundaries; Microstructure; Molecular dynamics; Nanocomposites; Nanocrystalline materials; Powder metallurgy; Sintering; Tantalum oxides; Vickers hardness, Dispersion strengthening; Grain boundary strengthening; Localized plastic deformation; Molecular dynamics simulations; Nanocrystalline particle; Particle-matrix interface; Stress-induced amorphization; Transverse rupture strength, Nanocrystals
Department/Centre:	Division of Mechanical Sciences > Aerospace Engineering(Formerly Aeronautical Engineering)
Date Deposited:	18 Jan 2021 10:48
Last Modified:	18 Jan 2021 10:48
URI:	http://eprints.iisc.ac.in/id/eprint/67589

Actions (login required)

View Item