CAJ | 학술논문

采用铸锭冶金法制备Al-Zn-Mg-Cu-Zr、Al-Zn-Mg-Cu-Er-Cr和Al-Zn-Mg-Cu-Zr-Er-Cr合金.通过金相显微镜、透射电镜的观察,和硬度、强度、腐蚀性能测试,对比Al-Zn-Mg-Cu-Zr、Al-Zn-Mg-Cu-Er-Cr和Al-Zn-Mg- Cu-Zr-Er-Cr合金的再结晶行为和性能.结果表明,Al-Zn-Mg-Cu-Zr合金中添加微量Er、Cr后生成的含Zn、Mg、Cu 的(Al,Cr)3(Zr,Er)相细小弥散,与基体共格,可钉扎位错,稳定亚结构,阻碍亚晶长大及晶界的迁移,从而抑制铝合金基体的再结晶,使合金在510℃仍能保持细小的亚晶组织,再结晶起始温度升高至500℃;在保持高的断裂韧性的同时,合金的应力腐蚀和剥落腐蚀抗力提高,应力腐蚀开裂界限应力强度因子KISCC由10.9 MPa/m1/2升高到22.4 MPa/m1/2,剥落腐蚀由EB+升高至EA+.
채용주정야금법제비Al-Zn-Mg-Cu-Zr、Al-Zn-Mg-Cu-Er-Cr화Al-Zn-Mg-Cu-Zr-Er-Cr합금.통과금상현미경、투사전경적관찰,화경도、강도、부식성능측시,대비Al-Zn-Mg-Cu-Zr、Al-Zn-Mg-Cu-Er-Cr화Al-Zn-Mg- Cu-Zr-Er-Cr합금적재결정행위화성능.결과표명,Al-Zn-Mg-Cu-Zr합금중첨가미량Er、Cr후생성적함Zn、Mg、Cu 적(Al,Cr)3(Zr,Er)상세소미산,여기체공격,가정찰위착,은정아결구,조애아정장대급정계적천이,종이억제려합금기체적재결정,사합금재510℃잉능보지세소적아정조직,재결정기시온도승고지500℃;재보지고적단렬인성적동시,합금적응력부식화박락부식항력제고,응력부식개렬계한응력강도인자KISCC유10.9 MPa/m1/2승고도22.4 MPa/m1/2,박락부식유EB+승고지EA+.
Al-Zn-Mg-Cu-Zr, Al-Zn-Mg-Cu-Er-Cr and Al-Zn-Mg-Cu-Zr-Er-Cr alloys were prepared by cast metallurgy. The recrystallization behavior and perperties of Al-Zn-Mg-Cu-Zr, Al-Zn-Mg-Cu-Er-Cr and Al-Zn-Mg-Cr-Zr-Er-Cr alloys were compared by optical microscopy, transmission electron microscopy, tensile test and corrosion resistance measurement. The results show that the dispersed L12-structured Zn, Mg, Cu, Cr-containing Al3(Zr,Er) dispersoids can strongly pin dislocations, stabilize substructures and inhibite the movement of boundaries. A small subgrain structure is maintained even heated at 510℃ in Al-Zn-Mg-Cu-Zr-Er-Cr alloy. Hence, the recrystallization temperature of Al-Zn-Mg- Cu-Zr-Er-Cr alloys reaches to 500℃. By combined additions of Er and Cr, the critical stress intensity (KISCC) increases from 10.9 MPa/m1/2 to 22.4 MPa/m1/2 and exfoliation corrosion increases from EB+ to EA+, with the improved strength, fracture toughness and ductility.