原始组织及加热方式对Al-5.8wt%Cu合金熔化行为的影响

利用DSC分析手段，研究了具有3种不同凝固组织的Al-5.8wt%合金在7种不同加热方式下的熔化开始温度和熔化热，发现凝固组织中存在的非平衡共晶在加热过程中大部分扩散溶解，溶入基体，剩余部分参与共晶熔化，其熔化开始温度与组织状态无关，随加热速度的增大略有升高，溶解部分的体积分散与组织状态和加热方式有关，随加热时间和非平衡相表面积的增大而增大。

Effect of Microstructure and Heating Conditions on Melting Behavior of Al-Cu 5.8wt% Alloy

DSC (Differential Scanning Calorimetry) was employed to investigate the initial melting tempera tuer and the fusion heat of Al-Cu 5.8wt% alloy with different microstruectures and heating conditions.During heating process,most of the non-equilibrium eutectic in the solidification structure dissolved due to the diffusion of the solute.The initial melting temperature does not depend on the microstructure,but slightly rises with increasing heating rate.The effect of heating conditions and microstructure on the fusion heat was studied as well,and the results show that the volume fraction of eutectic dissolved before melting increases with diffusion area and diffusion time.