固溶工艺对2099合金组织性能的影响

Microstructure and Property of 2099 Alloy with Different Solid Solution Processes

采用扫描电镜(SEM)、透射电镜(TEM)和力学性能测试等实验手段,研究了单级固溶和强化固溶工艺对2099合金型材组织性能的影响规律。结果表明:型材基体中分布着呈球状或板条状的Al-Cu-Mg相及无规则的Al-Cu-Mn-Fe脆性相。固溶态下,随着固溶或预固溶温度的升高,粗大析出相的固溶效果得到明显改善,Al-Cu-Mg相基本上固溶到基体中,Al-Cu-Mn-Fe相的尺寸减小、数量降低,但尚未完全固溶到基体中;合金的强度随着固溶或预固溶温度的升高而降低,而塑性获得不同程度的提高。时效态下,随着固溶或预固溶温度的升高,合金塑性指标降低,时效强化趋缓,时效强化相演化规律表现为:T_1相的密度增大,尺寸减小,θ'相、δ'相及δ'/β'等亚稳相的比例减小。

Effects of single and strengthening solution processes on microstructure and properties of 2099 alloy were studied by scanning electron microscope （SEM）, transmission electron microscope （TEM） and mechanical property test. The results showed that spherical or lath-shaped A1-Cu-Mg phases and in＇egular Al-Cu-Mn-Fe phases were distributed in profile matrix. Under the solid solution treatment, the solid solution effect of coarse precipitation was improved greatly with the increase of solid solution or pre-solid solution temperature. Al-Cu-Mg phases nearly dissolved into the matrix, the size and quantity of Al-Cu-Mn-Fe phases decreased but did not completely dissolve into the matrix. The strength of 2099 alloy decreased while the elongation increased to some extent along with the increase of solid solution or pre-solid solution temperature. Under the aging treatment, the plastic index decreased with the increase of solid solution or pre-solid solution temperature, and the aging strengthening tended towards slow down. The evolution laws of the aging strengthening precipitation displayed that T1 phase increased in density with a smaller size, the proportion of metastable phases decreased, such as θ′, δ′ and δ＇/β′.