摘要
采用铸锭冶金法制备Al-6.0Zn-2.0Mg-0.12Zr和Al-6.0Zn-2.0Mg-0.2Sc-0.12Zr 2种合金,借助力学性能测试、金相显微镜、透射电子显微镜、扫描电镜等手段分别对其热轧态、固溶态和时效态的组织性能进行对比观察分析。研究结果表明:复合添加Sc和Zr可明显细化合金的铸态晶粒,更好地抑制合金变形组织的再结晶,使主要强化相η′相更加细小、均匀、弥散,明显提高Al-Zn-Mg合金的力学性能。在固溶状态下,含Sc的Al-Zn-Mg-Zr合金抗拉强度、屈服强度比未添加Sc的合金分别提高40 MPa和54 MPa;在时效状态下,抗拉强度和屈服强度分别提高25 MPa和35 MPa;微量Sc和Zr对Al-Zn-Mg合金的强化作用主要源于含Sc和Zr化合物对合金起到了细晶强化、亚结构强化和析出强化作用。
Al-6.0Zn-2.0Mg-0.12Zr and Al-6.0Zn-2.0Mg-0.2Sc-0.12Zr alloys were prepared by ingot-metallurgy. Their properties and microstructure during different treatments were observed and analyzed by mechanical property testing, optical microscope （OM）, transmission electron microscope （TEM） and scanning electron microscope （SEM）. The results show that minor Sc, Zr addition can refine alloy ingots and restrict recrystallization of deforming microstructure remarkably during hot rolling. They make η＇ phase finer, more homogeneous and disperse. At the same time, minor Sc and Zr make the mechanical properties of Al-Zn-Mg alloys increase greatly. The tensile strength and yield strength of Al-Zn-Mg-Zr alloy with minor Sc addition rise by 40 MPa and 54 MPa after solution treatment respectively, and rise by 25 MPa and 35 MPa after aged treatment respectively. Grain strengthening, substructure strengthening and dispersion strengthening are responsible for the increase of strength of Al-Zn-Mg alloy with Sc and Zr.
出处
《中南大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2008年第5期975-979,共5页
Journal of Central South University:Science and Technology
基金
国家重点基础研究发展规划资助项目(G2005CB623705)
