Powder metallurgy processes – Powder metallurgy processes with heating or sintering – Consolidation of powder prior to sintering
Reexamination Certificate
2007-01-05
2010-02-23
Wyszomierski, George (Department: 1793)
Powder metallurgy processes
Powder metallurgy processes with heating or sintering
Consolidation of powder prior to sintering
C419S018000, C419S063000, C516S078000, C264S621000
Reexamination Certificate
active
07666349
ABSTRACT:
The present invention provides a method of gel-casting WC—Co cemented carbide powder, where the resulting gelled body can be of complex shape and has a high green density, a good homogeneity and sufficiently good mechanical properties for the gelled body to be demolded and dried without significant shape-distortions and cracking. The method relates to the forming of a gelled body through the gelling of an aqueous slurry of WC—Co cemented carbide powder with good dispersion characteristics, where the gelling is achieved by the temperature induced polymerization reaction between a monomer and a cross-linker, catalyzed by a free-radical initiator. By further subjecting the body to drying, heating, and sintering, a dense cemented carbide body is obtained.
REFERENCES:
patent: 2698232 (1954-12-01), Golibersuch
patent: 3351688 (1967-11-01), Kingery et al.
patent: 4894194 (1990-01-01), Janney
patent: 5028362 (1991-07-01), Janney et al.
patent: 5145908 (1992-09-01), Janney et al.
patent: 6066279 (2000-05-01), Walls et al.
patent: 6228299 (2001-05-01), Janney et al.
patent: 2002/0010219 (2002-01-01), Bergstrom et al.
patent: 2009/0113810 (2009-05-01), Laarz et al.
patent: 0 737 656 (1996-10-01), None
patent: 1 153 652 (2001-11-01), None
patent: 1 440 956 (2004-07-01), None
E. Laarz and L. Bergstrom, The effect of anionic polyelectrolytes on the properties of aqueous silicon nitride suspensions, Journal of the European Ceramic Society, vol. 20 (2000), p. 431-440.
L. Chongzhi et al. The Compatibility of Polycarboxylate-Type Superplasticizers with Cement. Journal of Wuhan University of Technology—Mater. Sci. Ed., vol. 20, No. 3, Sep. 2005, p. 95-98.
A. M. Kjeldsen et al.—Relating the molecular structure of comb-type superplasticizers to the compression rheology of MgO suspensions. Cement and Concrete Research, vol. 36, (2006), p. 1231-1239.
E. Laarz et al.—Dispersing Multi-Component and Unstable Powders in Aqueous Media Using Comb-Type Anionic Polymers, Journal of American Ceramic Society, vol. 89, No. 6, (Published Online: May 8, 2006), p. 1847-1852.
Sigmund et al., “Novel Powder-Processing Methods for Advanced Ceramics,” J. Am. Ceram. Soc., 83 (7), 2000, pp. 1557-1574.
Janney et al., “Development of Low-Toxicity Gelcasting Systems,” J. Am. Ceram. Soc., 81(3), 1998, pp. 581-591.
Andersson Karin
Laarz Eric
Drinker Biddle & Reath LLP
Sandvik Intellectual Property AB
Shevin Mark L
Wyszomierski George
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