Magnesium-aluminium alloy powders, although widely used in the polishing process on variable scales, also have a potential to be explosive. Having a thorough understanding of the thermal aspects of magnesium-aluminium alloy powder ensures process safety and is essential for developing an adequate emergency system. This study analysed the influence of the particle size, ranging between 105 and 420 μm on the thermal characteristics of magnesium-aluminium. The results revealed that at a dust concentration of 1750 g/m³, 105, 210, and 420 μm magnesium-aluminium alloy powders exhibited a maximum explosion pressure of 0.97, 0.86, and 0.78 MPa, respectively. The limiting oxygen concentration values of 105, 210, and 420 μm samples were 4, 13, and 15 vol.%, respectively. The apparent activation energies E_a of 105, 210, and 420 μm samples were 286.5–70.6, 165.2–39.9, and 224.8–168.8 kJ/mol, respectively. Furthermore, the flammability parameters exhibited greater reactivity for smaller particle sizes, i.e., the minimum ignition temperature sharply decreased from 700 to 550 °C. Thus, this study provides valuable insights into the combustion characteristics and the severity of the dust explosion hazards of magnesium-aluminium alloy powders in order to ensure better safety standards in the metal processing industry.

镁铝合金粉末虽然广泛用于各种规模的抛光过程，但也有潜在的爆炸性。对镁铝合金粉末的热学方面的透彻了解可确保工艺安全，并且对于开发适当的应急系统至关重要。该研究分析了粒径在 105 至 420 μm 之间对镁铝热特性的影响。结果表明，在粉尘浓度为 1750 g/m ^{3 时}，105、210 和 420 μm 镁铝合金粉末的最大爆炸压力分别为 0.97、0.86 和 0.78 MPa。105、210 和 420 μm 样品的极限氧浓度值分别为 4、13 和 15 vol.%。表观活化能E_一个的105，210，和420微米样品286.5-70.6，165.2-39.9，和224.8-168.8千焦/摩尔，分别。此外，可燃性参数对较小的粒径表现出更大的反应性，即最低着火温度从 700 ℃急剧下降到 550 ℃。因此，本研究为镁铝合金粉末的燃烧特性和粉尘爆炸危险的严重程度提供了宝贵的见解，以确保金属加工行业的安全标准更高。