(太原理工大學(xué) 材料科學(xué)與工程學(xué)院，太原 030024)
摘 要: 研究了復(fù)合變質(zhì)對過共晶鋁硅合金組織和性能的影響，實(shí)驗(yàn)結(jié)果表明：經(jīng)采用ZXH復(fù)合變質(zhì)劑變質(zhì)處理后，過共晶鋁硅合金中的初晶硅晶粒平均尺寸由變質(zhì)前的250μm變?yōu)?5μm，抗拉強(qiáng)度由變質(zhì)前的178MPa提高到236MPa，沖擊韌度由變質(zhì)前的7J/cm2提高到15.4J/cm2。所使用的這種新型變質(zhì)劑具有同時(shí)細(xì)化初晶硅和共晶硅的功效，且具長效性。由此說明，這種復(fù)合變質(zhì)劑是一種強(qiáng)效變質(zhì)劑，工藝寬容性好， 便于在生產(chǎn)中推廣應(yīng)用。
關(guān)鍵字: 過共晶鋁硅合金；復(fù)合變質(zhì)；晶粒細(xì)化
structures and properties of
hypereutectic Al-Si alloy
（College of Materials Science and Engineering，
Taiyuan University of Technology，Taiyuan 030024，China）
Abstract:The effect of composite modifier on structures and properties of hypereutectic Al-Si alloy was studied. The results of experiment show the average grain size of primary Si phase in hypereutectic Al-Si alloy is changed to 35μm from 250μm，σb is changed to 236MPa from 178MPa. Impact toughness is changed to 15.4J/cm2 from 7J/cm2. At the same time，the novel modifier has the effect of fining primary Si phase and the effect is long term. So the composite modifier is a kind of strong effect modifier with perfect technology tolerance.
Key words: hypereutectic Al-Si alloy；composite modification；grain fining
