烧结温度对铁镍代钴硬质合金组织和性能的影响

Effect of sintering temperature on microstructure and properties of cemented carbide with iron and nickel-based bonders

采用传统粉末冶金工艺制备了WC+TiC+Ni+Fe硬质合金,研究了不同烧结温度对铁镍代钴硬质合金显微组织和性能的影响。结果表明:烧结温度为1 400～1 480℃时,合金组织正常,无石墨相和η相产生。试样的密度随烧结温度的上升而逐渐增加。在研究的烧结温度范围内,WC+TiC+Ni+Fe合金的硬度和抗弯强度值都是先升高,再缓慢降低。试验最佳烧结温度为1 440℃,材料的综合力学性能最好,硬度和抗弯强度值达到"双高",其值分别为91.6 HRA和1 720 MPa。并且此时合金的切削性能与传统的WC+TiC+Co合金相当。

The effect of sintering temperature on microstructure and properties of WC＋TiC＋Ni＋Fe cemented carbide prepared by traditional powder metallurgy process was investigated.The results show that normal structure without graphite phase and η phase appears in alloys with the sintering temperature from 1 400 ℃ to 1 480 ℃.The density of the alloys increases gradually with the increasing of the sintering temperature.In the sintering temperature scope of this research,the hardness and bending strength of the alloys both firstly increase then decrease with increasing sintering temperature and appear maximum values at 1 440 ℃.The best sintering temperature is 1 440 ℃,because the synthesized properties of materials are best.At this temperature,the alloys appear the maximum hardness and bending strength of 91.6 HRA and 1 720 MPa respectively.At the same time,the cutting performance is close to the traditional WC＋TiC＋Co alloy.