钙在镁合金熔炼中的阻燃机理

熔炼了钙的质量分数为0.5%~5.0%,铝的质量分数为9.0%的10种镁合金,研究了Ca的加入对合金阻燃效果的影响.分别取定量的10种合金在700℃的高温下进行氧化增重的测量,并对合金表面的氧化形貌进行了观察.实验结果表明:镁合金加入钙后,其表面在高温下生成了CaO及少量MgO的复合致密氧化膜,这层氧化膜隔绝了空气,阻止了镁的燃烧;当钙的质量分数为3.5%时,可起到良好的阻燃效果.

On the Ignition-Proof Behavior of Ca During Mg Alloy Melting

Investigates the effect of Ca addition on the ignition-proof behavior of 10 kinds of molten Mg alloys, in which the Ca content was 0.5wt%-5.0wt% and Al content 9.0wt%. All the specimens of equal weight taken from those alloys were measured at 700°C for their weight increments due to oxidation, and their oxidized surface morphologies were observed. The results revealed that a dense composite CaO film containing a bit of MgO grows up on alloy surface at high temperature after adding Ca to the alloy, and the film is thus isolated from air to prevent Mg from burning. The ignition-proof effect is favorable if the Ca content in Mg alloy is 3.5wt%.