合金元素对Fe基金刚石节块胎体组织及性能的影响

选取Fe、Cu、Sn、Ni四种金属粉末作为烧结金刚石节块的胎体材料，设计混料试验预测成分变化对胎体性能的影响规律。结果表明:胎体中主要含α-Fe相、γ（Fe，Ni）相、Cu_13.7Sn固溶体和Cu₃Sn化合物。随Sn质量分数的升高，Cu_13.7Sn固溶体减少，脆性Cu₃Sn相增多，当Sn质量分数增大到一定程度后，组织中Cu_13.7Sn固溶体全部转化成Cu₃Sn脆性相，因此，胎体硬度先增高后趋于稳定；Sn质量分数越高，胎体中脆性相越多，割裂基体，胎体抗弯强度下降。Ni易固溶于Cu、Fe中，产生固溶强化，Ni质量分数升高，胎体硬度和抗弯强度均有一定程度的提高；在Sn质量分数较低时，Cu质量分数越高，Cu_13.7Sn固溶体量越多，胎体硬度下降；在Sn质量分数较高时，Cu质量分数越高，组织中脆性Cu₃Sn相量越多，胎体硬度提高。Cu易与Ni、Fe形成置换式固溶体，产生固溶强化作用，Cu质量分数的升高对胎体抗弯强度有一定程度的提高。

Effect of alloy elements on microstructures and properties of Fe-based matrixes for diamond segment

Fe-based matrixes for diamond segments were produced by Fe, Cu, Sn, and Ni powders. The mixture experiment was designed to predict the effect of element content on the matrixes performance. In the results, the matrix consists of α-Fe phase, γ(Fe, Ni) phase, Cu_13.7Sn solid solution, and the brittle phase of Cu₃Sn compounds. With the increase of Sn mass fraction, the content of Cu_13.7Sn solid solution by mass decreases, and the content of Cu₃Sn brittle phase by mass increases. When the Sn mass fraction increases to a certain extent, all the Cu_13.7Sn solid solution in microstructures is transformed into Cu₃Sn brittle phase, resulting that the matrix hardnes increases first and then tends to be stable. The higher the Sn mass fraction is, the more brittle phases in the matrix are, which will separate the matrix and lower the bending strength. Ni has the effect of solution strengthening in Cu and Fe, therefore the hardness and bending strength of the matrix are improved with the increase of Ni content by mass. At the lower Sn content by mass, the content of Cu_13.7Sn solid solution by mass increases with the increase of Cu content, resulting in the lower hardness of the matrix. At the higher Sn content by mass, the content of Cu₃Sn brittle phase by mass increases with the increase of Cu content, resulting in the higher hardness. Cu has the effect of solution strengthening in Ni and Fe, thus improving the bending strength of the matrix.