ABSTRACT

Al-Sn immiscible alloys possess enhanced tribological properties with increased fatigue strength, which makes them competent among self-lubricating bearing materials. In the present work, a direct chill (DC) casting simulator has been designed and manufactured to cast Al-Sn alloy by forced convection technology. The study embodies two different mechanisms for mechanical forced convection (MFC) by: (i) high shear (HS) rotor-stator device, (ii) conventional stirrer (CS) without stator. Shearing rate of 800 rpm for 60 seconds were kept constant for both the cases. Severe segregation of Sn has been observed in CS-DC cast billet due to prevailed phase separation and gravity sedimentation of Sn-rich phase from Al matrix. However, in the case of HS-DC cast billet uniform distribution of Sn and fine equiaxed grains throughout the volume of the billet has been achieved.

摘要

Al-Sn 不混溶合金具有增强的摩擦学性能和更高的疲劳强度，这使得它们在自润滑轴承材料中具有竞争力。在目前的工作中，已经设计和制造了一个直接冷却 (DC) 铸造模拟器，用于通过强制对流技术铸造铝锡合金。该研究通过以下方式体现了机械强制对流 (MFC) 的两种不同机制：(i) 高剪切 (HS) 转子-定子装置，(ii) 不带定子的传统搅拌器 (CS)。两种情况下 800 rpm 的剪切速率保持恒定 60 秒。在 CS-DC 铸坯中观察到 Sn 的严重偏析，这是由于 Al 基体中富锡相的普遍相分离和重力沉降。然而，