CAJ | 학술논문

为提高Al-Zn-Mg-Cu合金的强度,利用喷射成形的方法制备了含锰Al-Zn-Mg-Cu合金锭,并利用X射线衍射(XRD)、光镜(OP)、扫描电镜(SEM)、透射电镜(TEM)和示差扫描热分析(DSC)研究了其微观组织特征.结果表明:喷射沉积坯主要由晶粒尺寸为5～25 μm的细小等轴晶粒、MgZn2 和Al6Mn相组成.纳米级的MgZn2颗粒弥散分布于基体,而平均尺寸为5 μm的Al6Mn一次相颗粒沿晶界析出.沉积合金中也发现了少量的CuAl2, Al3Zr 和共晶组织.沉积坯中缩孔疏松的体积分数约为12%.DSC分析结果说明大部分溶质原子在喷射成形过程中析出,在450 ℃以下的加热过程中没有明显的热反应发生.随着退火温度的升高,基体晶粒和Al6Mn颗粒单调长大,但Al6Mn颗粒的长大速率显著低于基体晶粒的长大速率.当退火温度高于375 ℃时,基体晶粒迅速长大.
위제고Al-Zn-Mg-Cu합금적강도,이용분사성형적방법제비료함맹Al-Zn-Mg-Cu합금정,병이용X사선연사(XRD)、광경(OP)、소묘전경(SEM)、투사전경(TEM)화시차소묘열분석(DSC)연구료기미관조직특정.결과표명:분사침적배주요유정립척촌위5～25 μm적세소등축정립、MgZn2 화Al6Mn상조성.납미급적MgZn2과립미산분포우기체,이평균척촌위5 μm적Al6Mn일차상과립연정계석출.침적합금중야발현료소량적CuAl2, Al3Zr 화공정조직.침적배중축공소송적체적분수약위12%.DSC분석결과설명대부분용질원자재분사성형과정중석출,재450 ℃이하적가열과정중몰유명현적열반응발생.수착퇴화온도적승고,기체정립화Al6Mn과립단조장대,단Al6Mn과립적장대속솔현저저우기체정립적장대속솔.당퇴화온도고우375 ℃시,기체정립신속장대.
With the aim to improve the strength of Al-Zn-Mg-Cu alloy, the alloy billet containing Mn was produced by spray forming method, and the microstructural features were investigated using X-ray diffraction (XRD), optical microscopy (OM), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and differential scanning calorimetry (DSC). The results show that the billet mainly consists of fine equiaxial grains of MgZn2 and Al6Mn with size ranging from 5 μm to 25 μm. Nano-scaled MgZn2 is dispersed in the as-sprayed alloy, primary Al6Mn particles are precipitated at grain boundaries with an average size of 5 μm. A few CuAl2, Al3Zr and eutectic are also found in as-sprayed Al alloy. The volume fraction of the porosity is about 12%. DSC result indicates that most of the solutes are precipitated during spray forming process, and no obviously thermal effects occur below 450 ℃. Both matrix grains and Al6Mn particles grow monotonously with the increase of annealing temperature, but the growth rate of Al6Mn particles is markedly lower than that of Al grains, and the matrix grains grow rapidly when the annealing temperature is above 375 ℃.