TiB_(2)原位增强铝基复合材料的制备及其性能研究

Preparation and Properties of TiB_(2)In-situ Reinforced Aluminum Matrix Composites

采用原位自生技术制备了TiB_(2)含量分别为3wt%、5wt%和8wt%的TiB_(2)/Al铝基复合材料。通过金相组织分析、电镜扫描分析,从微观机理上对原位自生TiB_(2)相的生成状态进行了分析。结果表明,生成的TiB_(2)相尺寸约1~2μm,均匀地分布在基体中,同时,组织中存在少量Al3Ti相剩余;随着TiB_(2)含量的增加,铝基复合材料的抗拉强度逐渐增加,当TiB_(2)含量为5wt%时,复合材料的抗拉强度最高达到110 MPa;伸长率逐渐下降,由纯铝时的22.5%下降至8wt%TiB_(2)含量时的15.5%。

TiB_(2)/Al composites with TiB_(2) contents of 3wt%,5wt%and 8wt%were prepared by in-situ technology.The generating state of the in-situ TiB_(2) phase from the microscopic mechanism was analyzed by metallographic structure analysis and scanning electron microscope analysis.The results show that,the size of TiB_(2) phase is about 1-2μm,which is uniformly distributed in the matrix.At the same time,there are a small amount of Al3Ti phase surplus in the metallographic structure.With the increase of TiB_(2) content,the tensile strength of the composites increases gradually.When the TiB_(2) content is 5wt%,the tensile strength of the composites reaches 110 MPa,and the elongation decreases gradually,down from 22.5%in pure aluminum to 15.5%at 8wt%TiB_(2) content.