Al-5Ti-1B添加量和熔体保温时间对2024铝合金铸态组织的影响  

Effect of Adding Level of Al-5Ti-1B and Melt Holding Time on Microstructure of As-Cast 2024 Aluminum Alloy

作　　者：李滔[1,2] 王顺成 郑开宏 周海涛[2] 

机构地区：[1]广东省工业技术研究院金属加工与成型技术研究所,广东广州510650 [2]中南大学材料科学与工程学院,湖南长沙410083

出　　处：《铸造》2014年第8期839-843,共5页Foundry

基　　金：广东省科技厅产学研结合项目(2009A080205004;2012B091100475;2012B090600051)

摘　　要：研究了电磁搅拌连续铸挤Al-5Ti-1B晶粒细化剂添加量和熔体保温时间对2024铝合金铸态组织的影响。结果表明:添加0.1%的Al-5Ti-1B,可使2024铝合金的铸态组织从167.4μm的粗大枝晶细化到59.4μm的等轴晶。随着Al-5Ti-1B的添加量从0.1%逐渐增加到0.4%,2024铝合金的晶粒进一步细化,但晶粒细化效应逐渐减弱。当Al-5Ti-1B添加量为0.4%,2024铝合金被细化为平均直径为34.3μm的等轴晶。添加0.1%的Al-5Ti-1B并静置1 min,2024铝合金晶粒被细化至91.3μm。保温5 min,晶粒被细化为58.6μm的等轴晶;保温时间延长至120 min,晶粒未见明显长大。试验结果表明,电磁搅拌连续铸挤Al-5Ti-1B细化2024铝合金具有晶粒细化效果好、响应时间短和持续时间长的优点。Al-5Ti-1B grain refiner was prepared by continuous casting and extrusion process with electromagnetic stirring. The effect of Al-5Ti-1B grain refiner on microstructure of as-cast 2024 aluminum alloy was studied. The results show that when the Al-5Ti-1B addition is 0.1%, the microstructure of 2024 aluminum alloy is refined from coarse dendrite grain with grain average diameter of 167.4 μm to equiaxed grain with grain average diameter of 59.4μm. With increasing the addition of Al-5Ti-1B from 0.1% to 0.4%, the microstructure of 2024 aluminum alloy is further refined while the grain refinement effect is weakened. When the Al-5Ti-1B addition is 0.4%, the grain average diameter of 2024 aluminum alloy is refined to 34.3 μm. The grain average diameter of 2024 aluminum alloy with 0.1% Al-5Ti-1B and holding 1 min is refined to 91.3 μm, When the holding time is 5 min, the grain is refined to 58.6 μm. With the holding time prolonged to 120 min, grain growth is not obviously. The experimental results indicate that the Al-5Ti-1B used as the grain refiner of 2024 aluminum alloy possesses the characteristics of quick response time, strong anti-fading ability and long duration time.

关 键 词：2024铝合金 晶粒细化 Al-5Ti-1B 电磁搅拌 连续铸挤 

分 类 号：TG292[金属学及工艺—铸造] TG146.21[一般工业技术—材料科学与工程]