In the present research work, the effect of various aluminum contents on the microstructure of spheroidal graphite cast irons produced via the in-mold process was investigated. Samples containing 0, 3.7, 5.5, 6.4 and 7.5 wt% aluminum were cast and characterized by optical microscopy (OM), scanning electron microscopy (SEM), X-ray diffraction analysis (XRD) and hardness test. It was observed that by increasing the Al content from 0 to 7.5 wt%, the micro-hardness of pearlite and ferrite phases increases by 228 and 254 Vickers, respectively. Moreover, the addition of aluminum led to an increase in the nodule count from 168 to 668 per mm², reduction in the nodule diameter from 21.4 to 8.8 µm and also reduction in the sphericity from 65 to 48%. The obtained results revealed that varying aluminum content affects the precipitated pearlite morphology. This seems to be the result of aluminum reaction with carbon and the change in both carbon activity and rate of diffusion and also the aluminum atom behavior in the solid solution of Fe–Al–C alloys.

在本研究工作中，研究了各种铝含量对通过模内工艺生产的球墨铸铁组织的影响。铸造含有0、3.7、5.5、6.4和7.5 wt％铝的样品，并通过光学显微镜（OM），扫描电子显微镜（SEM），X射线衍射分析（XRD）和硬度测试进行表征。观察到，通过将Al含量从0增加到7.5wt％，珠光体和铁素体相的显微硬度分别增加了228和254维氏硬度。此外，铝的添加使结核数从每mm ^2的168增加到668，结节直径从21.4减小到8.8 µm，球形度从65％减小到48％。获得的结果表明，变化的铝含量会影响沉淀的珠光体形态。这似乎是铝与碳反应以及碳活性和扩散速率以及铁-铝-碳合金固溶体中铝原子行为变化的结果。