Study on Microstructure and Mechanical Properties of WC-10Ni3Al Cemented Carbide Prepared by Different Ball-Milling Suspension

In this paper, WC-10Ni3Al cemented carbides were prepared by the powder metallurgy method, and the effects of ball-milling powders with two different organic solvents on the microstructure and mechanical properties of cemented carbides were studied. We show that the oxygen in the organic solvent can be absorbed into the mixed powders by ball-milling when ethanol (CH3CH2OH) is used as a ball-milling suspension. This oxygen leads to the formation of α-Al2O3 during sintering, which improves the fracture toughness, due to crack deflection and bridging, while the formation of η-phase (Ni3W3C) inhibits the grain growth and increases the hardness. Alternatively, samples milled using cyclohexane (C6H12) showed grain growth during processing, which led to a decrease in hardness. Therefore, the increase of oxygen content from using organic solvents during milling improves the properties of WC-Ni3Al composites. The growth of WC grains can be inhibited and the hardness can be improved without loss of toughness by self-generating α-Al2O3 and η-phase (Ni3W3C).

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Microstructure and Mechanical Properties of Sintered Fibrous Monolith Cemented Carbide

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.815.233 ◽

2013 ◽

Vol 815 ◽

pp. 233-239

Author(s):

Xue Quan Liu ◽

Cun Guang Ding ◽

Chang Hai Li ◽

Yi Li ◽

Li Xin Li ◽

...

Keyword(s):

Mechanical Properties ◽

Fracture Toughness ◽

Crack Propagation ◽

Fracture Energy ◽

Bending Strength ◽

Extrusion Process ◽

Cemented Carbide ◽

Cemented Carbides ◽

Microstructure And Mechanical Properties

A fibrous monolith cemented carbide with WC-6Co as cell and WC-20Co as cell boundaries was produced through hot co-extrusion process in this paper. The density, hardness, bending strength and fracture toughness of the fibrous monolith cemented carbide were tested, and the fracture and crack propagation were observed by metalloscope and SEM. The results showed that the bending strength and fracture toughness of the fibrous monolith cemented carbides was remarkably improved 71.91% and 45.7% respectively, while the hardness was slightly decreased 1% compared with WC-6Co composites. It is the reason that the tougher shell WC-20Co with higher bending strength and fracture toughness can absorb more fracture energy, which can slow down and prevent the crack propagating from brittle core WC-6Co.

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Effect of MgO-Y2O3 Additions on Microstructure and Mechanical Properties of Al2O3-TiCN Composites

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1058.176 ◽

2014 ◽

Vol 1058 ◽

pp. 176-179

Author(s):

Zhi Lin Zhang ◽

Wei Ming Guo ◽

Shang Hua Wu ◽

Yang You

Keyword(s):

Mechanical Properties ◽

Fracture Toughness ◽

Grain Growth ◽

Abnormal Grain Growth ◽

Microstructure And Mechanical Properties

The effect of MgO-Y2O3 additives on densification, microstructure and mechanical properties of hot-pressed Al2O3-TiCN composites was studied. The MgO-Y2O3 additions had little influence on densification of Al2O3-TiCN composites. The Al2O3-TiCN composites without additives had coarsening microstructure, whereas that containing 0.25wt%MgO-0.5wt%Y2O3 had a noticeable finer microstructure and good mechanical properties. The increase of fracture toughness were attributed to the addition of MgO and Y2O3 together with the TiCN particles to inhibit the abnormal grain growth of Al2O3.

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Effect of (Ni,Mo) and (W,Ti)C on the Microstructure and Mechanical Properties of TiB2 Ceramic Tool Materials

Materials Science Forum ◽

10.4028/www.scientific.net/msf.723.233 ◽

2012 ◽

Vol 723 ◽

pp. 233-237 ◽

Cited By ~ 2

Author(s):

Tong Chun Yang ◽

Chuan Zhen Huang ◽

Han Lian Liu ◽

Bin Zou ◽

Hong Tao Zhu ◽

...

Keyword(s):

Mechanical Properties ◽

Fracture Toughness ◽

Grain Size ◽

Flexural Strength ◽

Grain Growth ◽

Vickers Hardness ◽

Ceramic Tool ◽

Tool Materials ◽

Sintering Additive ◽

Microstructure And Mechanical Properties

TiB2-(W,Ti)C composites with (Ni,Mo) as sintering additive have been fabricated by hot-pressing technique, and the microstructure and mechanical properties of the composites have been investigated. (Ni,Mo) promotes grain growth of the composites. In the case of 7vol.% (Ni,Mo), the grain size decreases consistently with an increase in the content of (W,Ti)C. When the proper content of (W,Ti)C is added to TiB2 composites, the growth of matrix grains is inhibited and the mechanical properties of the composites are improved. The best mechanical properties of the composites are 1084.13MPa for three-point flexural strength, 7.80MPa•m 1/2 for fracture toughness and 17.92GPa for Vickers hardness.

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Influence of Al2O3 Addition on the Microstructure and Mechanical Properties of Pressureless Sintered Ce-TZP

Materials Science Forum ◽

10.4028/www.scientific.net/msf.492-493.783 ◽

2005 ◽

Vol 492-493 ◽

pp. 783-0 ◽

Cited By ~ 2

Author(s):

Shui Gen Huang ◽

Lin Li ◽

Jef Vleugels ◽

Pei Ling Wang ◽

Omer Van der Biest

Keyword(s):

Mechanical Properties ◽

Fracture Toughness ◽

Grain Size ◽

Grain Growth ◽

Vickers Hardness ◽

Good Combination ◽

Al2o3 Content ◽

Pressureless Sintering ◽

Sintering Time ◽

Microstructure And Mechanical Properties

Mixtures of 12 mol% CeO2-stabilised ZrO2 with 5 to 20 wt % Al2O3 were prepared and densified through pressureless sintering in air at 1450° C for 1 to 4 h. The influence of the Al2O3 content and sintering time on the phase constitution, microstructure and mechanical properties of the as-sintered composites were investigated. Fully dense Ce-TZP/Al2O3 ceramics with a good combination of hardness and fracture toughness can be obtained by pressureless sintering in air for only 1 h. The addition of Al2O3 to Ce-TZP improves the mechanical properties and suppresses ZrO2 grain growth. The average ZrO2 grain size increases with increasing sintering time and decreasing Al2O3 content. This leads to an increase in toughness. An excellent fracture toughness of 14.3 MPam1/2 in combination with a Vickers hardness of 9.14 GPa was obtained for 12 mol % CeO2-TZP with 5 wt % Al2O3, sintered for 4 h.

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Microstructure and Mechanical Properties of Si3N4-Fe3Si Composites Prepared by Gas-Pressure Sintering

Materials ◽

10.3390/ma11071206 ◽

2018 ◽

Vol 11 (7) ◽

pp. 1206

Author(s):

Jiasuo Guan ◽

Laifei Cheng ◽

Mingxing Li

Keyword(s):

Mechanical Properties ◽

Fracture Toughness ◽

Crack Deflection ◽

Gas Pressure ◽

Interface Debonding ◽

Abnormal Growth ◽

Pull Out ◽

Uniform Microstructure ◽

Microstructure And Mechanical Properties ◽

Gas Pressure Sintering

Si3N4-Fe3Si composites were prepared using Fe-Si3N4 as the source of Fe3Si by gas-pressure sintering. By adding different amounts of Fe-Si3N4 into the starting powders, Si3N4-Fe3Si composites with various Fe3Si phase contents were obtained. The microstructure and mechanical properties of the composites were investigated. With the increase of Fe-Si3N4 contents, the content and particle size of Fe3Si both increased. When more than 60 wt. % Fe-Si3N4 were added, the abnormal growth of Fe3Si particles occurred and oversized Fe3Si particles appeared, leading to non-uniform microstructures and worse mechanical properties of the composites. It has been found that Fe3Si particles could toughen the composites through particle pull-out, interface debonding, crack deflection, and particle bridging. Uniform microstructure and improved mechanical properties (flexural strength of 354 MPa and fracture toughness of 8.4 MPa·m1/2) can be achieved for FSN40.

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Microstructure and Properties of Ultrafine Cemented Carbides Prepared by Microwave Sintering of Nanocomposites

Crystals ◽

10.3390/cryst10060507 ◽

2020 ◽

Vol 10 (6) ◽

pp. 507

Author(s):

Yanju Qian ◽

Zhiwei Zhao

Keyword(s):

Mechanical Properties ◽

Fracture Toughness ◽

Grain Size ◽

Vickers Hardness ◽

Sintering Temperature ◽

Microwave Sintering ◽

Raw Material ◽

Cemented Carbides ◽

Microstructure And Mechanical Properties ◽

Average Grain Size

Ultrafine cemented carbides were prepared by microwave sintering, using WC-V8C7-Cr3C2-Co nanocomposites as a raw material. The effects of sintering temperature and holding time on the microstructure and mechanical properties of cemented carbides were studied. The results show that the ultrafine cemented carbides prepared at 1300 °C for 60 min have good mechanical properties and a good microstructure. The relative density, Vickers hardness, and fracture toughness of the specimen reach the maximum values of 99.79%, 1842 kg/mm2 and 12.6 MPa·m1/2, respectively. Tungsten carbide (WC) grains are fine and uniformly distributed, with an average grain size of 300–500 nm. The combination of nanocomposites, secondary pressing, and microwave sintering can significantly reduce the sintering temperature and inhibit the growth of WC grains, thus producing superfine cemented carbides with good microstructure and mechanical properties.

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Microstructure and Mechanical Properties of Laminated Buckypaper/SiC Composite

Materials Science Forum ◽

10.4028/www.scientific.net/msf.816.147 ◽

2015 ◽

Vol 816 ◽

pp. 147-151

Author(s):

Xing Li ◽

Peng Xiao Huang ◽

Hui Peng ◽

Ying Zhou

Keyword(s):

Mechanical Properties ◽

Fracture Toughness ◽

Magnetron Sputtering ◽

Young’S Modulus ◽

Young's Modulus ◽

Rf Magnetron Sputtering ◽

Crack Deflection ◽

Nanoindentation Testing ◽

Microstructure And Mechanical Properties

The laminated Buckypaper/SiC composite was prepared by RF magnetron sputtering. For comparison, the monolithic SiC was also prepared in the present study. The microstructure and morphology of the prepared samples were characterized by SEM and XRD. The Young’s modulus, hardness and stiffness of the samples were investigated by nanoindentation testing. The results showed that the Buckypaper/SiC composite had an obviously multilayered microstructure at the nanoscale. Furthermore, the fracture toughness of the laminated Buckypaper/SiC composite could be improved by crack deflection and platelet pullout mechanisms. The laminated Buckypaper/SiC composite had higher Young’s modulus and stiffness than that of the monolithic SiC. However, its hardness was lower than that of monolithic SiC.

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Ultrafine WC-10Co cemented carbides fabricated by electric-discharge compaction

Journal of Materials Research ◽

10.1557/jmr.2004.0324 ◽

2004 ◽

Vol 19 (8) ◽

pp. 2240-2244 ◽

Cited By ~ 17

Author(s):

X.Y. Wu ◽

W. Zhang ◽

W. Wang ◽

F. Yang ◽

J.Y. Min ◽

...

Keyword(s):

Mechanical Properties ◽

Fracture Toughness ◽

Grain Size ◽

Electric Discharge ◽

Holding Time ◽

Conversion Process ◽

Cemented Carbides ◽

Microstructure And Mechanical Properties ◽

Spray Conversion

This research investigates the microstructure and mechanical properties of ultrafine WC-10Co cemented carbides fabricated by an electric-discharge compaction (EDC) process, from powder synthesized by a spray-conversion process (SCP). Due to a short holding time during EDC, a grain size as small as 120 nm can be achieved. We also found that dispersion of pores in WC-Co cemented carbides may contribute to fracture toughness, besides the bridging ligament mechanism.

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Microstructure, chemical aspects, and mechanical properties of TiB2/Si3N4 and TiN/Si3N4 composites

Journal of Materials Research ◽

10.1557/jmr.1994.2349 ◽

1994 ◽

Vol 9 (9) ◽

pp. 2349-2354 ◽

Cited By ~ 38

Author(s):

Jow-Lay Huang ◽

Shih-Yih Chen ◽

Ming-Tung Lee

Keyword(s):

Mechanical Properties ◽

Fracture Toughness ◽

Silicon Nitride ◽

Chemical Stability ◽

Large Deflection ◽

Crack Deflection ◽

Toughening Mechanism ◽

Β Phase ◽

Microstructure And Mechanical Properties

The chemical stability of TiB2 and TiN in a silicon nitride matrix under various conditions of temperature and gaseous environments was investigated. The addition of TiB2 and TiN on the microstructure and mechanical properties was also studied. No trace of interactions between TiN and Si3N4 was noticed. The addition of TiB2 to Si3N4 enhanced conversion of the α to β phase of the Si3N4 matrix. Observations of BN and TiN indicated a possible reaction between TiB2 and Si3N4. The fracture toughness of Si3N4 was substantially enhanced with the addition of TiB2 or TiN, while the strength was decreased. Crack deflection was the major toughening mechanism in a Si3N4/TiB2 composite. Most of the microcracks passed through TiN particles and cleavaged along preferred orientations with large deflection angles.

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