蛇形通道浇注制备7075铝合金半固态浆料  

Preparation of Semi-Solid 7075Aluminum Alloy Slurry by a Serpentine Pouring Channel

作　　者：朱文志[1] 毛卫民[1] 杨斌[1] 宋晓俊[1] 

机构地区：[1]北京科技大学材料科学与工程学院

出　　处：《特种铸造及有色合金》2013年第2期145-148,共4页Special Casting & Nonferrous Alloys

基　　金：国家重点基础研究发展计划(973计划)资助项目(2011CB606302)

摘　　要：采用蛇形通道浇注制备7075铝合金半固态浆料,研究了浇注温度、弯道数量和弯道直径对7075铝合金半固态浆料组织的影响。结果表明,当浇注温度为660～675℃时,可以制备出质量较好的7075铝合金半固态浆料,且管道内挂料较少;在相同温度条件下,随着弯道数量增加或弯道直径减小,初生α-Al的平均晶粒尺寸减小、形状因子提高。在制备7075铝合金半固态浆料过程中,合金熔体在具有一定弧度且封闭的蛇形弯道内流动并多次改变流动方向,具有类似"搅拌"功能,使得初生晶核逐渐演变为球形或近球形晶粒。The semi-solid slurry of 7075 aluminum alloy was prepared through a serpentine pouring chan- nel, and influences of pouring temperature ,the curve numbers and the curve diameters in the serpentine channel on the microstructure of semi-solid 7075 alloy slurry were investigated. The results demonstrate that the semi-solid 7075 aluminum alloy slurry with satisfied quality can be generated by a serpentine pouring channel and the solid shell inside the channel can be avoided with the pouring temperature in the range of 660℃～675 ℃. With a given pouring temperature, the equivalent size of the primary a-A1 grains is decreased and the shape factor is increased with the increase of the curve numbers or the de- crease of the curve diameters. During the slurry preparation of semi-solid 7075 aluminum alloy, the alloy melt changes flow direction many times when it flows in a curved and closed serpentine channel, which result in the primary nuclei gradually evolving effect of “stirring” in the serpentine curve.

关 键 词：7075铝合金 半固态浆料 蛇形通道 初生Α-AL 

分 类 号：TG249.9[金属学及工艺—铸造]