摘要
综述了Al-Si系合金中共晶Si变质的研究进展,总结了主要变质剂的应用现状以及影响变质效果的主要因素,总结了变质剂对铸件气孔形成的影响以及变质剂与晶粒细化剂的相互作用。Na和Sr变质剂的研究多集中于变质导致的铸锭或铸件气孔增多的原因及改进方法。冷却速率和合金元素是影响变质效果的重要因素,如何提高低冷却速率下多元AlSi系合金中共晶Si变质等级是重要研究方向之一。Sr和α-Al晶粒细化剂之间存在相互毒化作用,其本质是Sr与细化颗粒之间发生反应,使熔体中的有效变质剂和细化剂含量均降低。通过合理控制变质剂和细化剂的含量及添加顺序等工艺措施,可同时达到变质共晶Si和细化α-Al的目的。此外,开发新型Al-(Si)-Sr-(Ti)-B中间合金也是避免相互毒化作用的有效手段。
Recent progress in eutectic silicon modification of Al-Si alloys was summarized,and application status of the main modifier and key factors affecting modification treatment were reviewed,focusing on influences of modifiers on the porosity in castings and the interaction between modifiers and grain refiners.Recently,the research on the widest used Na and Sr series modifiers is concentrated on the mechanism and solutions on porosity increase in castings caused by modification.The cooling rates and alloying elements are two important factors affecting the modification.The method to improving the modification level of eutectic silicon in multi-element Al-Si alloys at a lower cooling rate is still an important research direction.The nature of mutual poisoning effect between Sr andα-Al grain refiners is the reaction between Sr and refinement particles resulting in efficient content reduction of both modifier and grain refiner.By rational control of content of modifier and grain refiner in the melt and the addition technique,the well-modified eutectic silicon and fineα-Al grains can be achieved.In addition,development of novel Al-（Si）-Sr-（Ti）-B master alloy is also an efficient way to avoiding mutual poisoning.
出处
《特种铸造及有色合金》
CAS
CSCD
北大核心
2016年第9期924-930,共7页
Special Casting & Nonferrous Alloys
基金
中国铝业股份有限公司2016年重大科技专项资助项目
关键词
共晶Si
变质
气孔
冷却速率
相互作用
Eutectic Silicon
Modification
Porosity
Cooling Rate
Interaction
