超低温轧制对2524铝合金显微组织及力学性能的影响

Effect of cryogenic rolling on microstructure and mechanical properties of 2524 aluminum alloy

采用光学显微镜、X射线衍射(XRD)、扫描电镜(SEM)、布氏硬度计和电子万能试验机等研究了超低温轧制对2524铝合金板材显微组织和力学性能的影响。结果表明:超低温轧制后2524合金中主要存在S(Al_(2)CuMg)相、θ(Al_(2)Cu)相。超低温轧制使板材的晶粒尺寸变小,第二相粒子沿晶界分布,位错密度显著提高,位错强化效果显著。经超低温轧制后板材的抗拉强度和硬度分别为551 MPa和171 HBW,比室温轧制分别提高了69 MPa和21 HBW,但伸长率相比室温轧制有所降低。与室温轧制相比,超低温轧制后板材的织构强度减弱,织构类型也发生了变化,室温轧制板材织构类型为α织构,而超低温轧制后织构类型主要为Goss织构。

Effect of cryogenic rolling on microstructure and mechanical properties of 2524 aluminum alloy plate was studied by means of optical microscope,X-ray diffraction(XRD),scanning electron microscopy(SEM),Brinell hardness tester and electronic universal testing machine.The results show that the microstructure of the 2524 aluminum alloy after cryogenic rolling is mainly composed of S(Al_(2)CuMg)phase andθ(Al_(2)Cu)phase.The cryogenic rolling can reduce the grain size of the plate,the second phase particles are distributed along the grain boundary,the dislocation density is significantly increased,and the dislocation strengthening effect is significant.After cryogenic rolling,the tensile strength and hardness of the plate are 551 MPa and 171 HBW,respectively,which are 69 MPa and 21 HBW higher than that after room temperature rolling,but the elongation is lower than that after room temperature rolling.Compared with room temperature rolling,the texture strength of the plate after cryogenic rolling decreases and the texture type also changes.The texture type of the plate after room temperature rolling isαtexture,and the texture type after cryogenic rolling is mainly Goss texture.