第二代FeCuCo预合金粉末的烧结与力学性能研究

Study on the sintering and mechanical properties of the second generation FeCuCo pre-alloyed powder

采用国产真空热压烧结机制备了第二代FeCuCo预合金粉末的胎体试样,着重研究了不同烧结温度对胎体的断口形貌、相对密度、硬度和抗弯强度的影响。结果表明:在选定的不同热压烧结温度下,胎体的断口均为沿晶断裂和穿晶断裂的混合型断口,胎体的晶粒尺寸比较均匀;随着烧结温度的升高,胎体内的晶粒逐渐长大,但没有发生异常长大现象,胎体的相对密度先略有升高然后恒定不变,硬度一直呈下降趋势,抗弯强度先升高后下降;在30 MPa保压6 min的条件下,第二代FeCuCo预合金粉末的最佳烧结温度为850℃,此时胎体的相对密度为97.5%,硬度为105.5 HRB,抗弯强度为1 839.14MPa。

The samples of the second generation FeCuCo pre-alloyed powder matrix were prepared by using vacuum sintering machine, and the fracture morphology, relative density, hardness and bending strength of matrix at different sintering temperatures were investigated. The results showed that the fracture morphology of matrix was intergranular fracture and transgranular fracture and the grain size of matrix was uniform at different sintering temperatures. With the sintering temperature increasing, the grain size of matrix gradually increased, and no abnormal coarsening of grains was observed. The relative density of matrix slightly increased then kept constant, the hardness of matrix gradually decreased, the bending strength of matrix increased then followed by a decrease. Under the pressure of 30MPa and a dwell time of 6 minutes, the optimum sintering temperature of the second generation FeCuCo pre-alloyed powder is 850℃, the relative density of matrix is 97.5 %, the hardness of matrix is 105.5 HRB and the bending strength of matrix is 1839. 14 MPa. The second generation FeCuCo pre-alloyed powder demonstrates great application potential in replacing pure cobalt powder.