摘要
采用硬度、电导率测试、金相显微镜、X线衍射、扫描电镜、透射电镜和能谱分析技术,研究均匀化温度对合金组织和性能的影响。研究结果表明:铸态合金由α-Al固溶体和非平衡共晶相组成;490～510℃均匀化,Mg2Si相从过饱和固溶体中析出,在510℃以上均匀化,随着温度的升高,Mg2Si又逐步回溶到基体中,560℃均匀化,Mg2Si相和过剩单质Si完全溶解;随着均匀化温度的升高,非平衡析出物鱼骨状共晶形态逐渐消失,针状β-AlMnFeSi溶解、断裂,转变为具有更高(Mn+Fe)/Si比值颗粒状α-Al(MnFe)Si相,析出相在高温均匀化过程中聚集、球化;560℃均匀化,析出物的连续网状结构转变成链状结构,析出物演化为等轴粒状α-Al(MnFe)Si相。均匀化过程中合金中析出弥散α-Al(MnFe)Si相;在490～560℃保温6h均匀化处理,温度升高,合金的硬度和电导率分别升高和降低。
The effect of homogenization treatment temperature on microstructure and properties of 6082 aluminum alloys were investigated by using hardness and electrical conductivity measurement, optical microscope （OM）, X-ray diffraction （XRD）, scanning electronic microscope （SEM）, energy dispersive spectrum （EDS） and transmission electron microscopy （TEM）. The results show that the as-cast alloy consists of supersaturated solid solution and unequilibrium eutectic phases. Supersaturated solid solution changes into equilibrium Mg2Si phase at 490-510 ℃; equilibrium phases are dissolved into matrix when the homogenization temperature is higher than 510 ℃; Mg2Si phase and Si phase dissolved into matrix completely at 560 ℃. With the increase of annealing temperature, the eutectic morphology of precipitates disappears gradually, acicular β-AIMnFeSi phase transforms to spherical α-Al（MnFe）Si phase and the ratio of n（Mn＋Fe）/n（Si） in AIMnFeSi phase increases. The precipitates is changed into spherical α-Al（MnFe）Si phase after annealing at 560 ℃ for 6 h. During homogenization, dispersive α-Al（MnFe）Si particles deposit in the alloy. The hardness increases and eonductivity decreases with the increase of annealing temperature.
出处
《中南大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2012年第3期911-917,共7页
Journal of Central South University:Science and Technology
基金
广东省教育部产学研结合项目(2009A080205001)
关键词
6082铝合金
温度
显微组织
球化
弥散相
6082 aluminum alloy
temperature
microstructures
spheroidization
dispersoid
