采用真空烧结工艺制备板状WC晶粒硬质合金,在800~1 200℃条件下以不同升温速率升温.采用XRD、SEM、EDS研究了固相烧结的升温速率对其显微组织及力学性能的影响.研究结果表明:在800~1 200℃温度区间内,随着升温速率的降低,硬质合金的硬度、抗弯强度、断裂韧性均有所提高;其中,随着800~1 000℃的升温速率的降低,硬质合金最终烧结体的组织变得均匀,二维结构中硬质相的晶粒长厚比升高,材料硬度提高趋势较大;随着1 000~1 200℃的升温速率的降低,硬质相晶粒细化,粘结相中固溶合金元素含量增加,材料抗弯强度提高的幅度较明显;同时降低800~1 000℃和1 000~1 200℃的升温速率,可使裂纹长度减小,裂纹偏转增强,大幅提高材料的断裂韧性.在800~1 200℃以2℃/min升温得到的烧结体可获得较均匀的显微组织,硬质相颗粒大部分呈板条状且颗粒长厚比较大,烧结体具有较好的力学性能.
参考文献
[1] | Kobayashi M .Development of disk-reinforced cemented carbides[J].International Journal of Refractory Metals and Hard Materials,1998,16(1):26-31.,1998. |
[2] | 吴恩熙,汪秀全,曾青,陈力.含板状WC晶粒硬质合金制备方法的研究[J].硬质合金,2006(02):75-78. |
[3] | Kitamura K,Kobayashi M,Hayashi K .Microstructural development and properties of new WC-Co base hardmetal prepared from Cox WyCx+C instead of WC[J].Journal of the Japan Society of Powder and Powder Metallurgy,2001,48(7):621-628.,2001. |
[4] | 李炯义,曹顺华,林信平.盘状WC晶粒硬质合金研究进展[J].粉末冶金技术,2005(05):378-382. |
[5] | Sommer M,Schubert W D,Zobetz E,et al .On the formation of very large WC crystals during sintering of ultrafine WC-Co alloys[J].International Journal of Refractory Metals and Hard Materials,2002,20(1):41-50.,2002. |
[6] | Kinoshita S,Saito T,Kobayashi M,et al .Microstructure and mechanical properties of new WC-Co base cemented carbide having highly oriented plate-like triangular prismatic WC grains[J].Journal of the Japan Society of Powder and Powder Metallurgy,2000,47(5):526-533.,2000. |
[7] | Kinoshita S,Kobayashi M,Hayashi K .High temperature strength of WC-Co base cemented carbide having highly oriented plate-like triangular prismatic WC grains[J].Journal of the Japan Society of Powder and Powder Metallurgy,2002,49(4):299-305.,2002. |
[8] | Kinoshita S,Saito T,Kobayashi M,et al .Mechanisms for formation of highly oriented plate-like triangular prismatic WC grains in WC-Co base cemented carbides prepared from W and C instead of WC[J].Journal of the Japan Society of Powder and Powder Metallurgy,2001,48(1):51-60.,2001. |
[9] | 蔡海燕.矿用硬质合金WC晶粒均匀性及板状形貌异常长大的控制[J].硬质合金,2014(04):230-235. |
[10] | 朱丽慧,赵海锋,黄清伟,马学鸣.高能球磨-热压烧结制备定向排布板状WC硬质合金[J].中南大学学报(自然科学版),2004(03):358-362. |
[11] | Schubert W D,Neumeister H,Kinger G,et al .Hardness to toughness relationship of fine-grained WC-Co hardmetals[J].International Journal of Refractory Metals and Hard Materials,1998,16(2):133-142.,1998. |
[12] | 李晨辉,余立新,熊惟皓.WC的粒度对WC-Co硬质合金断裂韧性的影响[J].硬质合金,2001(03):138-141. |
[13] | Lee D D,Kang S J,Yoon D N .Mechanism of grain growth and α-β' transformation during liquid-phase sintering ofβ'-sialon[J].Journal of the American Ceramic Society,1988,71(9):803-806.,1988. |
[14] | 李炯义 .利用纳米晶W、Co、C过渡相粉末制备硬质合金的研究[D].中南大学,2005. |
[15] | Kinoshita S,Kobayashi M,Taniguchi Y,et al .Effects of starting powder size and ball-milling time on microstructure of WC-Co base cemented carbides prepared from W+C+Co base mixed powder[J].Journal of the Japan Society of Powder and Powder Metallurgy,2003,50(5):377-384.,2003. |
[16] | 李志林,朱丽慧,卞凯强.板状WC晶种加入对硬质合金性能的影响[J].硬质合金,2009(03):157-160. |
[17] | Shatov A V,Firstov S A,Shatova I V .The shape of WC crystals in cemented carbides[J].Materials Science and Engineering:A,1998,242:7-14.,1998. |
[18] | 朱丽慧,刘坤,李志林 .含板状WC晶粒硬质合金的强韧化机制研究[J].稀有金属材料与工程,2011,40:443-446.Zhu Lihui,Liu Kun,Li Zhilin.Study on the hardening and toughening mechnisms of WC-Co cemented carbides with plate-like WC grains[J].Rare Metal Materials and Engineering,2011,40(Suppl.2):443-446.,2011. |
[19] | 张卫兵,吴志坚,袁红梅.片晶增韧硬质合金研究进展[J].硬质合金,2013(06):343-350. |
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