显微组织及性能
(哈尔滨工业大学金属精密热加工国防科技重点实验室，哈尔滨 150001)
摘 要: 研究了采用喷射沉积工艺制得的Al-5.5Cu/TiB2(20%)自生复合材料的沉积态及挤压态显微组织：沉积态组织细小， 颗粒分布均匀，颗粒与基体界面结合良好， 很少出现孔洞， 原铸态自生组织中呈针片状的TiAl3相消失而呈颗粒状分布，析出相细小弥散； 挤压态组织中孔洞基本弥合， 纵向组织具有一定方向性，颗粒分布有些不均匀(有一定的条带)。力学性能测试结果表明：喷射沉积后的Al-5.5Cu/TiB2自生复合材料的抗拉强度比铸态提高约50 MPa， 延伸率则提高500%左右，耐磨性能也有较大提高。
关键字: 喷射沉积 自生复合材料 显微组织 性能
（National Defense S and T Key Lab of Metal Precision Hot Working, Harbin Institute of Technology, Harbin 150001, P. R. China）
Abstract:The microstructures (both as-deposition and as-extruded) of Al-5.5Cu/TiB2(20%) in-situ composites prepared by spray deposition were studied. The grains(as-deposition) are fine and well-distributed, the needle and flake-shaped TiAl3 phase in as-cast changes to particle-shape, the precipitation is fine and dispersive; the porosity of the materials (as-extruded) almost disappears, but it is found that there are some strip-structures of TiB2 in the longitudinal direct ion. It is proved that the tensile strength of the materials prepared by spray deposition is elevated to 420 MPa, and the elongation of the materials is elevated about 4 times, meanwhile the wear resistance of the material is elevated.
Key words: spray deposition in-situ composites microstructure property
