摘要
用同轴双筒流变仪研究了在连续冷却的切变流动条件下,部分凝固Sn-15％Pb合金的流变性质。结果表明:在固相分数增加时,这种半固态浆液的流型从牛顿流体向假塑性流体、宾汉流体转化。当固相分数大于0.3以后,随着切变速率的降低,初生固相的形貌由菊花状向网络结构变化。在连续冷却的切变流功中。固相颗粒的聚集是固相生长的重要机制。因此,在连续冷却条件下的部分凝固合金,其表观粘度要高于在等温冷却条件下的情况。
The rheological features of partially solidified Sn-15％ Pb in continuously cooled shear flow were investigated using a concentric cylinder viscometer. The results show that with the increase of the fraction of solid, the types of fluids of semi-solid slurries vary from Newtonian, pseudoplastic to Bingham fluids. As the shear rate decreases, the morphology of primary solid changes from rosette to network with solid fraction greater than 0.3. In continuously cooled shear flow, the agglomeration of primary solid particles is the predominant growth mechanism, and it is the reason why the viscosity of partially solidified alloy under continuous cooling condition is higher than that under isothermal cooling.
出处
《东南大学学报（自然科学版）》
EI
CAS
CSCD
1989年第4期66-73,共8页
Journal of Southeast University：Natural Science Edition
基金
国家教委科学基金
