(中南大学 粉末冶金国家重点实验室， 长沙 410083)
摘 要: 研究了Co和Ti(CN)含量对梯度硬质合金的力学性能、 梯度结构的影响。 测试了梯度硬质合金刀片的切削性能。 结果表明： 随着合金钴含量的增多， 合金梯度层厚度增厚， 梯度结构越明显； 合金的强度提高， 磁饱和提高， 磁力、 硬度和密度减小。 随着合金Ti(CN)含量的增多， 合金梯度层厚度有变薄的趋势; 随合金的硬度提高， 合金的强度和密度减小。 切削试验表明： 具有梯度结构涂层硬质合金刀片的切削性能比无梯度结构涂层硬质合金刀片的切削性能优良。 达到同一磨损高度hB=0.15 mm时, 前者的切削寿命较后者提高了近一倍。 同时随着合金钴含量的增多， 硬质合金刀片的切削性能提高。
关键字: 硬质合金; 梯度结构; 强度; 硬度; 切削性能
gradient structure
（ State Key Laboratory of Power Metallurgy, Central South University,
Changsha 410083, China）
Abstract: The effect of cobalt and Ti(CN) content on the structure and properties of graded cemented carbides was studied . The results show that, with the increase of cobalt content, the gradient structure becomes more distinct and the thickness of gradient structure increases, meanwhile, the transverse rupture strength and the magnetism saturation increases, while the hardness, coersive force and the density decrease. With the increasing Ti(CN) content, the thickness of gradient structure decreases; meanwhile, the hardness and coersive force increase, while the transverse rupture strength and the density decrease. The cutting tests demonstrate that the cutting property of the coated cemented carbide with gradient structure is much better than those without gradient structure. The severability of the forth is about one and a half of that of the later at hB=0.15 mm. Meanwhile, with the increasing cobalt content, the cutting properties increase.
Key words: cemented carbide; gradient structure; strength ; hardness; cutting property
