TiB2/AlSi10Mg选区激光熔化成形组织与性能

采用选区激光熔化成形技术制备AlSi10Mg合金和TiB2/AlSi10Mg复合材料，利用XRD、SEM、TEM、万能拉伸实验机和维氏硬度计等对TiB2/AlSi10Mg复合材料的力学性能、组织结构等进行了表征分析。结果表明：AlSi10Mg合金中加入增强相TiB2后，其SLM成形件的致密度、屈服强度和断裂强度分别由96.8%、156.3 MPa和366.3 MPa增加至99.4%、170.1 MPa和413.4 MPa。TiB2/AlSi10Mg成形件屈服强度的提升主要来源于Orowan强化、弥散强化和细晶强化。与此同时，TiB2增强相的添加使得裂纹源增加，大幅度降低了AlSi10Mg合金的塑性（从8.5%下降到4.2%），其断裂机制由准解理断裂转变为解理断裂。

Microstructure and properties of TiB2/AlSi10Mg composite prepared by selective laser melting

AlSi10Mg alloy and TiB2/AlSi10Mg composite alloy were prepared by selective laser melting (SLM), and then the microstructure and mechanical properties were characterized and analyzed by X-ray diffraction (XRD), SEM, TEM, tensile test machine and Vickers hardness tester. The results indicate that once the TiB2 particles added into AlSi10Mg, density, yield strength and fracture strength of the SLM AlSi10Mg alloy improve from 96.8%, 156.3 MPa and 366.3 MPa to 99.4%, 170.1 MPa and 413 MPa, respectively. The raise of yield strength of TiB2/ AlSi10Mg is the result of Orowan strengthening, dispersion strengthening and fine grain strengthening. Moreover, crack source increases with the addition of TiB2, and the plasticity reduces from 8.5% to 4.2%. The fracture mechanism changes from quasi-cleavage fracture to cleavage fracture.