利用Master Sintering Curve晶粒长大方程模拟了200 nm WC-Co硬质合金固相烧结和液相烧结过程中WC晶粒的长大曲线,并与实际烧结实验相比较.烧结实验选用的WC的粒度为200 nm,采用球磨混料,经过普通模压,压制压力为200 MPa,制备出直径为20 mm、厚度为3～5 mm的压坯.烧结实验在管式炉中进行,烧结气氛为高纯氢气,加热速率为10℃·min<'-1>,烧结时间为10 min.结果表明:Master SinteringCruve模型在WC-Co硬质合金烧结过程中具有很好的适用性.计算出的品粒长大随烧结温度的变化与实际烧结实验具有很好的一致性.经过固相烧结,200 nm的WC长大到254 nm,烧结激活能为450 kJ·mol<'-1>,但体积扩散和晶界扩散机制的区别不是很明显.经过液相烧结WC颗粒继续长大到287 nm,此时固液相的界面反应控制整个烧结过程,烧结激活能为474 kJ·mol<'-1>.压坯烧结激活能的增加,将显著抑制在烧结过程中WC晶粒的长大.
参考文献
| [1] | Gille G;Szesny B.Submicro and ultrafine grained hardmetals for microdills and metal cutting inserts[A].,2001:102. |
| [2] | 林晨光 .中国超细和纳米晶WC/Co硬质合金的研究开发概况[J].中国钨业,2003,20(02):26. |
| [3] | 徐庆荣,黎先财,杨沂凤,王燕.超细碳化钨的制备及其性能研究[J].稀有金属,2009(01):133-136. |
| [4] | 范景莲,黄伯云,张传福,曲选辉,汪登龙.纳米钨合金粉末的制备技术与烧结技术[J].硬质合金,2001(04):225-231. |
| [5] | 李炯义,曹顺华,林信平.硬质合金中的晶粒长大抑制剂[J].硬质合金,2004(01):56-60. |
| [6] | 王洪涛,王旭,余永宁.纳米WC/Co硬质合金粉末烧结早期的晶粒长大研究[J].稀有金属与硬质合金,2005(01):18-21. |
| [7] | 吴恩熙,雷贻文.超细硬质合金中晶粒生长抑制剂的作用[J].硬质合金,2002(03):136-139. |
| [8] | Morton C W;Wills D J .The temperature ranges for maximum effectiveness of grain growth inhibitors in WC/Co alloys[J].International Journal of Refractory Metals and Hard Materials,2005,23:287. |
| [9] | Tikare V.Modeling microstructural evolution during sintering in a complex powder compact[A].,2002:221. |
| [10] | Hansen .Combined-stage sintering model[J[J].Journal of the American Ceramic Society,1992,75(05):1129. |
| [11] | Yoon Soo Han .Monte carlo simulation of anisotrophic grain growth in liquid phase sintering[J].Journal of the Korean Physical Society,2003,4(42):1058. |
| [12] | S.J. PARK;J.M. MARTIN;J.F. GUO .Densification Behavior of Tungsten Heavy Alloy Based on Master Sintering Curve Concept[J].Metallurgical and Materials Transactions, A. Physical Metallurgy and Materials Science,2006(9):2837-2848. |
| [13] | Park S J .Grain growth behavior of tungsten heavy alloy based on master sintering curve concept[J].Metallurgical and Materials Transactions,2006,37A:3337. |
| [14] | Konyashin I .On the mechanism of WC coarsening in WC-Co hardmetals with various carbon contents[J].Journal of Refractory Metals and Hard Materials,2008,36:1. |
| [15] | He Yanlin .Computer simulating the diffusion behavior of V and W in Co binder layer of WC-Co cemented carbide[J].Journal of Alloys and Compounds,2007,436:146. |
| [16] | Xu Wang;Zhigang Zak Fang;Hong Yong Sohn .Grain growth during the early stage of sintering of nanosized WC-Co powder[J].International Journal of Refractory Metals & Hard Materials,2008(3):232-241. |
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