(西北工業(yè)大學(xué)物理系，西安710072)
摘 要: 以擴(kuò)散為模型，并考慮界面反應(yīng)對初生相溶解過程的影響，建立了初生相在過熱熔體中的溶解動力學(xué)模型。同時以Al-18%Si(質(zhì)量分?jǐn)?shù))合金為對象，在1100 ℃過熱情況下，對該模型進(jìn)行了驗證，結(jié)果表明：該模型基本上能反應(yīng)該條件下初生硅的溶解特性。
關(guān)鍵字: 過共晶Al-Si合金；初生相；溶解動力學(xué)
（Department of Applied Physics, Northwestern Polytechnical University, Xi'an 710072, P.R.China）
Abstract:As well known, coarse primary silicon phase in Al-Si hypereutectic alloy dentsits mechanical properties, thus limits the application of this alloy. In addition, it has been found that primary silicon in Al-Si hypereutectic alloys was of higher chemical stability in the melt, and its dissolution behavior had directly influence on the freezing microstructure and on the mechanical properties of the alloy. From above, investigating on dissolution character for primary silicon is very emergent. Therefore, the dissolution process of primary silicon particles in Al-18%Si (mass fraction) alloy was studied both by melt overheating experiment and by theoretical analysis, and a dissolution model of primary silicon in the melt was established based on the atomic diffusion and taken account of interface reaction; the results show that the theoretic curve agrees with the experiment one at overheating temperature of 1100 ℃.
Key words: hypereutectic Al-Si alloy; primary phases; dissolution kinetics
