Impact Consolidation of the Tungsten Powder in the Wide Range of Temperatures. II. Mechanical Properties

O. I. Tolochyn, A. V. Laptev, I. Yu. Okun, Ya. I. Evich

I.M. Frantsevich Institute for Problems of Materials Sciences, NAS of Ukraine, 3 Academician Krzhizhanovskoho Str., UA-03680 Kyiv-142, Ukraine

Received: 27.11.2013. Download: PDF

Impact consolidation in vacuum of 0.0133 Pa of the usual tungsten powder with a size of particles of 6—10 microns is carried out at temperatures of 850, 1050, 1260, 1450, 1500, 1600, and 1640°C. The isothermal holding before consolidation was 20 min. The obtained samples with a diameter of 25—27 mm and a height of $\cong$ 10 mm cut on two parts, one of which is subjected to annealing at the temperature of 1600°C within the one hour. The annealed and not annealed parts of a sample cut on rectangular bars for determination of the density, structure, and mechanical properties. As established, the rather high mechanical properties are formed at a consolidation temperature above 1600°C, at which the strong interparticle interaction leading to transcrystalline breaking of samples is provided. Thus, the transverse rupture strength is equal to 1130 MPa, fracture toughness–9MPa$\cdot$m$^{1/2}$, Vickers hardness–4350 MPa, strength at compression–1380 MPa, and plasticity at compression–11%. Additional annealing of samples generally reduces their mechanical properties, except for strength and plasticity at the compression. Samples with high properties were characterized before annealing by transcrystalline breaking, but after annealing, they began to collapse by means of the intercrystalline mechanism.

Key words: powder, Tungsten, microstructure, impact consolidation.



PACS: 62.20.M-, 81.20.Ev, 81.40.Ef, 81.40.Gh, 81.40.Lm, 81.40.Vw

Citation: O. I. Tolochyn, A. V. Laptev, I. Yu. Okun, and Ya. I. Evich, Impact Consolidation of the Tungsten Powder in the Wide Range of Temperatures. II. Mechanical Properties, Metallofiz. Noveishie Tekhnol., 36, No. 2: 217—228 (2014) (in Russian)

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