Hot Pressing of Tungsten Monocarbide Nanopowder Mixtures by Electroconsolidation

Gevorkyan, É. S.; Rucki, Mirosław; Chishkala, V. A.; Kislitsa, M. V.; Siemiątkowski, Zbigniew; Morozow, Dmitrij

doi:10.12783/dtcse/fe2019/30678

Cited by 4 publications

(4 citation statements)

References 20 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Thus, a longer holding time is required so that diffusion and creep flow controlled mechanisms provide the final densification, but the prolongation of the holding time leads to significant, undesirable grain growth [ 34 ]. In contrast, electroconsolidation promotes the redistribution of the vacancies that contribute to the mass transfer, as is described in [ 35 ]. The equilibrium concentration of the vacancies near a pore is higher than that near the flat surface.…”

Section: Discussionmentioning

confidence: 99%

Feasibility of Cobalt-Free Nanostructured WC Cutting Inserts for Machining of a TiC/Fe Composite

et al. 2021

Self Cite

View full text Add to dashboard Cite

The paper presents results of investigations on the binderless nanostructured tungsten carbide (WC) cutting tools fabrication and performance. The scientific novelty includes the description of some regularities of the powder consolidation under electric current and the subsequent possibility to utilize them for practical use in the fabrication of cutting tools. The sintering process of WC nanopowder was performed with the electroconsolidation method, which is a modification of spark plasma sintering (SPS). Its advantages include low temperatures and short sintering time which allows retaining nanosize grains of ca. 70 nm, close to the original particle size of the starting powder. In respect to the application of the cutting tools, pure WC nanostructure resulted in a smaller cutting edge radius providing a higher quality of TiC/Fe machined surface. In the range of cutting speeds, vc = 15–40 m/min the durability of the inserts was 75% of that achieved by cubic boron nitride ones, and more than two times better than that of WC-Co cutting tools. In additional tests of machining 13CrMo4 material at an elevated cutting speed of vc = 100 m/min, binderless nWC inserts worked almost three times longer than WC-Co composites.

show abstract

Section: Discussionmentioning

confidence: 99%

Feasibility of Cobalt-Free Nanostructured WC Cutting Inserts for Machining of a TiC/Fe Composite

et al. 2021

Self Cite

View full text Add to dashboard Cite

show abstract

“…The abovementioned powder blends underwent sintering process in the graphite molds, using a modified electroconsolidation method, which has been described in detail elsewhere [41]. Graphite molds were lubricated with boron nitride to prevent their interaction with sintered specimens.…”

Section: Methodsmentioning

confidence: 99%

Combined Effect of CrB<sub>2</sub> Micropowder and VN Nanopowder on the Strength and Wear Re-sistance of Fe‒Cu–Ni–Sn Matrix Diamond Composites

Ratov¹,

Мечник²,

Rucki³

et al. 2023

Adv. Sci. Technol. Res. J.

View full text Add to dashboard Cite

The paper presents research results on the enhancement of diamond composites designed for tools application for mining industry, hard rocks cutting, able to withstand harsh conditions under heavy dynamical loads. In the present study, both CrB 2 micropowder and VN nanopowder additives were used in proportions up to 5 wt.% and 6 wt.%, respectively, together with the basic matrix composition of 51 wt.% Fe, 32 wt.% Cu, 9 wt.% Ni, and 8 wt.% Sn. Addition of both components, CrB 2 and VN, appeared to be advantageous in proportion of 2 wt.% and 4 wt.%, respectively. This composition exhibited the highest relative density of 0.9968, better than that without additives. Similarly, the highest values of compressive strength R cm and flexural strength R bm were reached for the composite with the same percentage of CrB 2 and VN. Compared to the composite with no addition of CrB 2 and VN, R cm improved by almost 70%, while R bm by 81%. Additionally, the abovementioned additives enhanced the ability of the matrix to prevent the diamond reinforcement from being torn out of the composite, which is very important under harsh working conditions of the cutting tools. The presence of CrB 2 micropowder and VN nanopowder promoted densification of the matrix and adhesion between the diamond grits and the Fe-Cu-Ni-Sn matrix.

show abstract

“…After obtaining a mixture, nanopowders underwent calcination at 800 °C during 1 h, and then were sintered using a patented hot-pressing device, described in detail elsewhere [ 22 ]. The sample was placed into the vacuum chamber and, after being heated by the electric current, underent mechanical pressure to form a dense, solid structure.…”

Section: Methodsmentioning

confidence: 99%

Peculiarities of the Phase Formation during Electroconsolidation of Al2O3–SiO2–ZrO2 Powders Mixtures

et al. 2022

Self Cite

View full text Add to dashboard Cite

This paper is devoted to the sintering process of Al2O3–SiO2–ZrO2 ceramics. The studied method was electroconsolidation with directly applied electric current. This method provides substantial improvements to the mechanical properties of the sintered samples compared to the traditional sintering in the air. The research covered elemental and phase analysis of the samples, which revealed phase transition of high-alumina solid solutions into mullite and corundum. Zirconia was represented mainly by tetragonal phase, but monoclinic phase was present, too. Electroconsolidation enabled samples to reach a density of 3.0 g/cm3 at 1300 °С, while the sample prepared by traditional sintering method obtained it only at 1700 °С. For the composite Al2O3—20 wt.% SiO2—10 wt.% ZrO2 fabricated by electroconsolidation, it was demonstrated that fracture toughness was higher by 20–30%, and hardness was higher by 15–20% compared to that of samples sintered traditionally. Similarly, the samples fabricated by electroconsolidation exhibited elastic modulus E higher by 15–20%. The hypothesis was proposed that the difference in mechanical and physical properties could be attributed to the peculiarities of phase formation processes during electroconsolidation.

show abstract

Hot Pressing of Tungsten Monocarbide Nanopowder Mixtures by Electroconsolidation

Cited by 4 publications

References 20 publications

Feasibility of Cobalt-Free Nanostructured WC Cutting Inserts for Machining of a TiC/Fe Composite

Feasibility of Cobalt-Free Nanostructured WC Cutting Inserts for Machining of a TiC/Fe Composite

Combined Effect of CrB<sub>2</sub> Micropowder and VN Nanopowder on the Strength and Wear Re-sistance of Fe‒Cu–Ni–Sn Matrix Diamond Composites

Peculiarities of the Phase Formation during Electroconsolidation of Al2O3–SiO2–ZrO2 Powders Mixtures

Contact Info

Product

Resources

About