铝合金粉末注射成形的基础问题

针对铝基粉末在注射成形工艺过程中易氧化并造成烧结致密化难的问题，提出了充分利用机械活化和化学反应及其协同作用，强化铝合金粉末成形坯烧结致密化过程的新思路。重点研究强化烧结助剂的作用机制和成分设计，混合粉末在高能球磨过程中表面氧化膜的形成、破碎以及颗粒间冷焊规律及其对烧结过程的影响。基于聚合物共混原理，设计多组元多功能粘结剂，该粘结剂不仅可以在较低的温度下脱除干净，而且可以对铝粉起到保护作用。该研究将为建立铝合金的粉末注射成形技术奠定理论和技术基础。

In view of the problem that the aluminum-based powder is easily oxidized during the powder injection molding (PIM) process, which makes it difficult to be densified, a new solution to this problem is put forward. Take full advantage of the mechanical activation and chemical reaction, as well as their synergistic effects, to enhance the sintering densification process of the PIM aluminum alloy. The main focus of this project is on the alloy design and the activation mechanism of sintering aids, the formation and disruption of the oxide layer, cold welding between particles during high energy ball milling process and its effect on the sintering process. Based on the principle of polymer blending, a multi-component and multi-functional binder system is designed. This binder system can be removed at relative low temperature, and it can also protect the aluminum powder at the same time. This project is expected to exert positive effect on the establishment of theoretical and technological foundation for net-shape forming of aluminum alloy components through powder injection molding technology.