High pressure sintering of cubic boron nitride compacts with Al and AlN
High pressure sintering of cubic boron nitride compacts with Al and AlN
复制标题
高压烧结立方氮化硼复合体与 Al 和 AlN
DOI：
10.1016/j.diamond.2008.07.002
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发表时间：
2008-12-01
影响因子：
4.1
通讯作者：
He, Duanwei
中科院分区：
文献类型：
--
作者：
Lv, Ran;Liu, Jin;He, Duanwei
立方氮化硼(CBN)压坯分别添加15wt.%Al和20wt.%AlN，在5.0 Gpa的高压下，在1300-1700℃的温度范围内烧结20min。研究了高压烧结样品的硬度、显微组织、相组成和切削性能。在CBN-Al系统中观察到了一个液相烧结和反应过程，X-射线衍射仪证实了烧结体中AlN和AlB_2的形成。扫描电子显微镜(SEM)分析表明，样品具有均匀的微观结构。材料的硬度随烧结温度的升高而降低，在1350℃时达到最高维氏硬度32.1Gila，而在CBN-AlN体系中，AlN颗粒在1500℃以下严重团聚，随着烧结温度的升高，AlN颗粒逐渐出现，AlN颗粒逐渐消失。当烧结温度为1600℃时，CBN-AlN复合材料的最高硬度达到29 Gpa。车削试验表明，添加15wt.%Al的CBN比添加20wt.%AlN的CBN具有更长的刀具寿命。结果表明，与CBN-AlN系相比，CrN-Al系更有利于获得烧结良好的CBN压坯。(C)2008爱思唯尔B.V.保留所有权利。
Cubic boron nitride (cBN) compacts, using 15 wt.% Al and 20 wt.% AlN respectively as additives, were sintered in the temperature range of 1300-1700 degrees C for 20 min under high pressure of 5.0 GPa. The hardness, microstructure, phase composition and cutting performance of the high pressure sintered samples were investigated. A liquid phase sintering and reaction process was observed in the cBN-Al system, which leads to the formation of AlN and AlB2 as confirmed by X-ray diffraction (XRD) in the sintered compacts. Scanning electron microscopy (SEM) analysis shows that the samples have a homogeneous microstructure. The hardness decreases with increase of sintering temperature and reaches the highest Vickers hardness of 32.1 Gila at 1350 degrees C. While in the cBN-AlN system, AlN grains agglomerate heavily at temperature below similar to 1500 degrees C. As the sintering temperature increasing, Al2O3 appeared and the AlN agglomeration disappeared gradually. A highest cBN-AlN composite hardness of 29 GPa was achieved when sintered at 1600 degrees C. Turning tests showed that cBN compacts with 15 wt.% Al as the additive has a longer tool life as compared to that with 20 wt.% AlN. Our results indicated that cRN-Al system is more favourable to obtain well-sintered cBN compacts comparing with the cBN-AlN system. (C) 2008 Elsevier B.V. All rights reserved.