The effect of the shape of WC crystals on the strength of cemented carbides is studied on WC-Ni alloys with small addition of TiC. It is found that the strength increases when the shape of WC crystals changes to a flatter triangular prism characterized by a lower value of the shape equiaxiality P{sub}(WC). The effect is interpreted in terms of decreasing the effective size of the critical defect that initiated the fracture of the material while the fracture toughness is not affected by the change of the shape of WC crystals. It is suggested that the decrease of the critical defect size can be explained by the decrease of the amount of sub-critical fracture along carbide-carbide boundaries due to a lower value of the contiguity and a relatively higher critical stress for trans-crystalline fracture through the carbide crystals in cemented carbides with flatter shape of WC crystals.
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机译：WC-Ni合金的WC-Ni合金中含有少量TIC，研究了WC晶体形状对粘合碳化物强度的影响。结果发现，当WC晶体的形状变为较大的三角形棱镜时，强度会增加，其特征在于形状equiAxiality p {sub}（wc）的较低值。根据减少引发材料骨折的关键缺陷的有效尺寸而解释效果，而裂缝韧性不受WC晶体形状的变化的影响。建议，由于邻近的邻近度的较低值和反晶骨折的较低值，可以通过沿碳化物 - 碳化物界限的亚临界裂缝的量减少来解释临界缺陷尺寸的减小。碳化物晶体中的碳化物碳化物，具有较平坦的WC晶体。
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