充型量对半固态铜合金铸造充型组织的影响

The Effect of Filling Amount on Microstructure of Semi-Solid Copper Alloy During Mold Filling Process

以半固态ZCuSn10铜合金为研究对象,利用自主设计的一套模具在Gleeble-1500热/力学模拟实验机上进行压缩实验,研究充型量对半固态铜合金铸造充型组织的影响。结果表明:在温度950℃,充型速度5 mm/s条件下,当充型量由20%增加到40%时,随着充型量增加,试样的组织发生明显改变。变形前期,试样基本保持半固态组织,固相晶粒由液相包裹,液相在变形外力作用下先于固相流动;随着充型量的增加,固液两相发生分离,液相相互聚集,冷却凝固形成树枝晶组织,并伴有缩孔、缩松等缺陷,致密度不高;固相晶粒之间发生严重塑性变形,相互粘连在一起,晶界模糊。

The semi-solid ZCuSn 10 copper alloy was used as the research object, the compression experiment was carried out on Gleeble-1500 thermal/mechanical simulator with a self-designed mold, studying the microstructure evolution of semi-solid copper alloy during mold filling process. The results show that the microstructure evolution of the sample is evolving with the increase of filling quantity from 20% to 40% under the condition of temperature 950 ~C and filling velocity 5 mm/s. At the initial stage of filling, the specimen remained essentially semi-solid, the solid phase grains are encapsulated by the liquid phase, the liquid phase flow ahead of solid in the deformation of external force; with the increase of deformation, solid-liquid two-phase separation occurs, the liquid phase gathered each other, dendrites organization appeared after cooling solidification, accompanied by shrinkage and dispersed shrinkage, density is not high; The solid grains have severe plastic deformation and adhere together, grain boundary blur or disappear.