微波强化烧结制备铁钴基金刚石锯片刀头

Fabrication of the diamond sawblade bits with Fe-Co metallic matrix by microwave strengthened sintering

采用微波烧结技术制备了低钴型Fe-Co基金刚石锯片刀头,利用圆柱谐振腔微扰法电磁特性测试系统评价了配方物料压坯的吸波特性,并结合物料在微波场中的升温特性设计了可行的微波烧结制度。采用SEM、致密度和硬度测试对比研究了微波烧结和常规烧结所得样品的微结构信息和力学性能。结果表明,对于低钴高铁型配方,在850℃下微波烧结获得的样品,其相对致密度和硬度即可分别达到96.63%和99.4HRB,微波烧结在最大升温速率为32.5℃/min时能保证烧结体组织均匀。与常规烧结方法相比,在获得同等级力学性能的前提下,微波强化烧结可将温度降低至900℃以下,显著缩短了烧结总时间,在金属基金刚石工具刀头烧结方面表现出良好的应用前景。

The iron-cobalt(Fe-Co)metallic matrix diamond sawblade bits with low cobalt were successfully fabricated through microwave sintering.The microwave-absorbing characteristic of the designed recipe compacts were estimated on an electromagnetic characteristic test system by applying the cylindrical resonant cavity perturbation method.The microwave sintering procedure was designed according to the heating characteristics of the material in the microwave field.The microstructure information and mechanical properties were investigated and compared by using scanning electron microscope(SEM),relative density and hardness tests in case of the microwave and conventional sintering method.The result showed the relative density and hardness reached 96.63%and 99.4HRB respectively for the low cobalt samples sintered at 850℃.In addition,the microstructure was still uniform when the samples was under microwave sintered at the temperature rate of 32.5℃/min.Compared with the conventional sintering method,on the premise of comparative mechanical properties,microwave strengthening sintering can significantly shorten the total sintering time and decrease the sintering temperature below 900℃to achieve similar mechanical properties of the product.The microwave heating technology shows an excellent application prospect in the field of the strengthen sintering for the metallic matrix diamond tool bits.