Comparative study on indentation fracture toughness measurements of cemented carbides
Comparative study on indentation fracture toughness measurements of cemented carbides
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硬质合金压痕断裂韧性测量的对比研究
DOI：
10.3176/eng.2006.4.07
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发表时间：
2006
期刊：
影响因子：
--
通讯作者：
M. Antonov
中科院分区：
文献类型：
--
作者：
F. Sergejev;M. Antonov
大多数金属材料的断裂韧性研究通常使用 V 形缺口技术、致密试样和圆形缺口拉伸试样。这些方法需要相当长的时间来进行样品制备和凹口几何控制。由于硬质相的脆性非常高，其中只有少数可以应用于硬质合金。这就是为什么开发了各种更快速、更简单的压痕断裂韧性 (IFT) 技术 [(上标 1, 2)]。压痕韧性测量结果主要取决于裂纹类型（Palmqvist 或中值/径向裂纹）的假设、用于计算断裂韧性的方程以及与材料相关和与材料无关的常数 [(上标 3)]。在目前的工作中，对 IFT 计算方法进行了比较研究，以找到适用于所研究材料（WC-Co、TiC-Fe/Ni）的可靠技术。标准和出版物推荐的几个陶瓷材料 IFT 方程用于评估断裂韧性，并与已发表的常规断裂韧性数据进行比较 [(上标 4, 5)]。只有少数方程可以可靠地估计硬质合金的断裂韧性。
Majority of the fracture toughness studies of metallic materials typically use the Chevron notch technique, compact specimens and round notched tensile specimens. These methods require considerable time for sample preparation and for the notch geometry control. Only a few of them can be applied for cemented carbides due to the very high brittleness of the hard phase. This is why various indentation fracture toughness (IFT) techniques have been developed [(superscript 1, 2)], which are more rapid and simple. Indentation toughness measurements results depend critically on the assumption about the crack type (Palmqvist or median/radial cracks), on the equations used for the calculation of fracture toughness and on the material-dependent and material-independent constants [(superscript 3)]. In the present work a comparative study of IFT calculation methods was carried out to find a reliable technique for studied materials (WC-Co, TiC-Fe/Ni). Several IFT equations for ceramic materials, recommended by standards and publications, were used for the evaluation of the fracture toughness and compared with published conventional fracture toughness data [(superscript 4, 5)]. Only few of the equations give reliable estimation of the fracture toughness of cemented carbides.