Synthesis and characterizations of ball-milled nanocrystalline WC and nanocomposite WC–Co powders and subsequent consolidations

El‐Eskandarany, M. Sherif; Mahday, Amir A; Mohamed, Hassan; Amer, Ashraf

doi:10.1016/s0925-8388(00)01155-5

Cited by 158 publications

(73 citation statements)

References 28 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Carburization of tungsten powder at high temperature is typically used to produce tungsten carbide. 4,5 With the goal of obtaining nanostructured powders, other techniques including, for example, ball milling, [6][7][8] spray conversion process (SCP), 9 and spray thermal decomposition, 5 have also been used recently. Moreover, 99% pure WC powders with 1-2 m particle size were prepared from elements through the Selfpropagating high-temperature synthesis (SHS) method in the presence of a highly exothermic mixture (Mg + Teflon) as reaction promoter.…”

Section: Introductionmentioning

confidence: 99%

“…Moreover, 99% pure WC powders with 1-2 m particle size were prepared from elements through the Selfpropagating high-temperature synthesis (SHS) method in the presence of a highly exothermic mixture (Mg + Teflon) as reaction promoter. 10 Regarding the consolidation stage, besides conventional sintering methods, hot pressing (HP) and hot isostatic pressing (HIP), 5,8 as well as other more recently developed techniques-for example, spark plasma sintering (SPS) 9,11,12 -are also used for the preparation of dense WC-Co composites. In particular, cemented functional gradient materials (FGM) carbide with four gradient layers (from 6 to 20 wt% Co) was fabricated by an automatic SPS system starting from fine (average particle size less than 0.5 m) WC powders.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Simultaneous spark plasma synthesis and consolidation of WC/Co composites

2005

View full text Add to dashboard Cite

The single-step synthesis and densification of the WC-6Co cemented carbide starting from elemental powders was obtained by the spark plasma sintering (SPS) technique. The operating conditions that guarantee the complete conversion of the reactants to the desired full dense material have been identified. Specifically, under the application of 800 A and a mechanical pressure of 40 MPa for about 200 s, a product with relative density higher than 99%, hardness of 14.97 ± 0.35 GPa, and 12.5 ± 1.0 MPa m 0.5 fracture toughness was obtained. A kinetic investigation of the SPS process was also performed. It revealed that an intermediate phase, i.e., W 2 C, is the first carbide formed during the carburization process. It was observed that the synthesis and sintering stages take place simultaneously. It was also found that as the applied pulsed current intensity was augmented, the synthesis/sintering time required decreased significantly.

show abstract

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Simultaneous spark plasma synthesis and consolidation of WC/Co composites

2005

View full text Add to dashboard Cite

show abstract

“…Зависимости твердости (а) и трещиностойкости (б) от содержания углерода в сплавах, полученных после обработки в газовой смеси () и без обработки (■) Благодаря малому размеру зерна значения твердости полученных после восполнения угле-рода образцов стехиометрического состава (партия № 5) значительно превосходят значения твер-дости субмикронных твердых сплавов [1; 2; 3]. Полученные образцы так же превосходят по твер-дости ультрамелкозернистые аналоги, полученные жидкофазным спеканием [20], горячим прессо-ванием [21], электроискровым и индукционным спеканием [22; 23]. Некоторое отставание в тре-щиностойкость можно объяснить большим размером зерен у аналогов [21; 23; 22].…”

Section: ученые запискиunclassified

Increasing Hardness and Fracture Toughness of Ultrafine Alloy WC-8CO-0.4VC-0.4CR3C2 by Adjusting the Carbon Content in the Sintering Initial Stage

Михайленко¹,

Mokritskii²

2017

uzknastu

View full text Add to dashboard Cite

Дворник Максим Иванович -кандидат технических наук, старший научный сотрудник Федерального государственного бюджетного учреждения науки Института материаловедения Хабаровского научного центра Дальневосточного отделения Российской академии наук (Россия, г. Хабаровск), тел (4212) Аннотация. В работе проведены исследования по регулированию концентрации углерода в ультрамелко-зернистом твердом сплаве WC-8Co-0,4VC-0,4Cr 3 C 2 за счет обработки пористых заготовок в газовой смеси CO + CO 2 на начальной стадии спекания в течение 50 мин при температуре 650 °С. На основе зависимостей концентрации углерода в полученных образцах от концентрации CO в газовой смеси были определены условия увеличения и уменьшения концентрации углерода. Установлено, что восполнение недостатка уг-лерода (0,37 масс.%) позволяет увеличить твердость (c HV1767 до HV1943) и трещиностойкость (с 5,8 до 8,4 МПам) ультрамелкозернистого твердого сплава WC-8Co-0.4VC-0.4Cr 3 C 2 . Показано наличие градиента твердости по глубине образцов, полученных при обработке в смесях с наибольшей и наименьшей концен-трациями CO. Построены зависимости твердости и трещиностойкости от содержания углерода в ультра-мелкозернистом сплаве.Summary. The authors present the adjustment of the carbon concentration in the ultrafine hard alloy WC-8Co-0.4VC-0.4Cr3C2 by treating porous work pieces in the gas mixture CO + CO2 at an initial sintering stage during 50 minutes at 650 °C. Based on the dependencies of carbon concentration in the obtained samples from the CO volume concentration in the gas mixture the conditions for increasing and decreasing of carbon concentration were determined. It was revealed that the restoring of carbon lack (0,37 mass.%) can induce the rising hardness (from HV1767 to HV1943) and toughness (from 5.8 to 8.4 MPam) of ultrafine hard alloy WC-8Co-0.4VC-0.4Cr3C2. The presence of hardness gradient depths for samples obtained by processing in the mixtures with the highest and the lowest concentration of CO is shown. The dependences of hardness and fracture toughness from the carbon content of the ultrafine alloys were drawn.Материал поступил 21.12.2016 56 Ученые запискиКомсомольского-на-Амуре государственного технического университета

show abstract

“…[2][3][4][5][6][7], но они либо дороги, либо малопроиз водительны, и поэтому их промышленное приме нение ограничено.…”

Section: Introductionunclassified

The effect of process sintering parameters on structure and properties of VK5 hard alloy of tungsten carbide SHS powder

Zaitsev¹,

Вершинников²,

Panov³

et al. 2015

Izv. vuzov, Porošk. metall. funkc. pokryt.

View full text Add to dashboard Cite

Synthesis and characterizations of ball-milled nanocrystalline WC and nanocomposite WC–Co powders and subsequent consolidations

Cited by 158 publications

References 28 publications

Simultaneous spark plasma synthesis and consolidation of WC/Co composites

Simultaneous spark plasma synthesis and consolidation of WC/Co composites

Increasing Hardness and Fracture Toughness of Ultrafine Alloy WC-8CO-0.4VC-0.4CR3C2 by Adjusting the Carbon Content in the Sintering Initial Stage

The effect of process sintering parameters on structure and properties of VK5 hard alloy of tungsten carbide SHS powder

Contact Info

Product

Resources

About