【摘要】 研究了少量的Ti和Al加入到Mg-4Zn-3.5Y-0.8Ca-0.5Si镁合金后对凝固组织所产生的影响。结果表明,在实际凝固条件下,Mg-4Zn-3.5Y-0.8Ca-0.5Si合金凝固过程中会发生明显的溶质再分配现象,最终形成粗大的树枝晶和厚大连续的晶界混合相;加入少量Ti或Al后,增加了Zn在-αMg中的固溶度,使实际条件下的非平衡凝固向近平衡凝固转变,使凝固末期的剩余液相减少,最终形成细化的不连续晶界。更多还原

【Abstract】 The effects of Ti/Al on of Mg-4Zn-3.5Y-0.8Ca-0.5Y-0.8Ca-0.5Si magnesium alloys were investigated.The results showed that coarse α-Mg dendrites and thick and continuously connected grain boundaries exist in the Mg-4Zn-3.5Y-0.8Ca-0.5Y-0.8Ca-0.5Si alloys due to significant solute re-distributions during solidification.With small amount addition of Ti or Al the solid solubility of Zn in α-Mg is increased and the disconnected thin grain boundaries are formed.The non-equilibrium solidification of the alloy is transformed to near-equilibrium solidification.更多还原