顯微組織及性能
(哈爾濱工業(yè)大學(xué)金屬精密熱加工國防科技重點(diǎn)實(shí)驗(yàn)室，哈爾濱 150001)
摘 要: 研究了采用噴射沉積工藝制得的Al-5.5Cu/TiB2(20%)自生復(fù)合材料的沉積態(tài)及擠壓態(tài)顯微組織：沉積態(tài)組織細(xì)小， 顆粒分布均勻，顆粒與基體界面結(jié)合良好， 很少出現(xiàn)孔洞， 原鑄態(tài)自生組織中呈針片狀的TiAl3相消失而呈顆粒狀分布，析出相細(xì)小彌散； 擠壓態(tài)組織中孔洞基本彌合， 縱向組織具有一定方向性，顆粒分布有些不均勻(有一定的條帶)。力學(xué)性能測(cè)試結(jié)果表明：噴射沉積后的Al-5.5Cu/TiB2自生復(fù)合材料的抗拉強(qiáng)度比鑄態(tài)提高約50 MPa， 延伸率則提高500%左右，耐磨性能也有較大提高。
關(guān)鍵字: 噴射沉積 自生復(fù)合材料 顯微組織 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
