合金成分和冷凝速率对Al-Mn合金中准晶相形成能力和热稳定性的影响(英文)

本文通过DTA和X射线衍射分析,研究了合金成分和冷凝速率对Al_(100-x)Mn_x(x=12.5,13.5,15.75,17.7,20.6和22.3at%)合金中准晶相形成能力和热稳定性的影响。结果表明:当Mn<16at%,准晶二十面体相的形成能力随合金锰含量的增加而增强,当Mn>16at%,合金中出现准晶十边形相,从而削弱了二十面体相的形成能力,当Mn>22at%,二十面体相几乎被完全抑制。准晶十边形相的形成能力随合金锰含量增加而不断增强。提高冷凝速率会增强二十面体相的形成能力。准晶二十面体相和十边形相的晶化温度均随合金锰含量增加而升高,但受冷凝速率的影响很小。

EFFECTS OF COMPOSITION AND COOLING RATE ON FORMING ABILITY AND THERMAL STABILITY OF QUASICRYSTALLINE PHASES IN AI-Mn ALLOYS

Effects of composition and cooling rate on the forming ability and thermal stability of quasi-crystalline phases in Al_(100-x) Mn_x(x=12.5,13.55,15.7,17.75,20.6 and 22.3 at%)lloys ave beeninvestigated by using DTA and X-ray diffraction analysis.The results show that in lloys contai-ning<16 at% Mn,the forming ability of the icosahedral phase increases as the Mn ontent increases.At higher Mn contents,the decagonal phase forms competitiveIy with the cosahedral phase andreplaces the latter progressively with the increase of Mn content.In lloys ontaining>22 at%Mn,the icosahedral phase is nearly suppressed.The forming ability of the cosahedral phase isincreased at higher cooling rates.The crystallization temperatures of the cosahedral and deca-gonal phases go up with the increase of Mn content,but remain nearly nchanged at different cool-ing rates.