多孔FeAl非水基凝胶注模成形的可控固化

Controllable Gelation of Non-aqueous Gel system for Porous FeAl intermetallic

摘要:

以铁粉及铝粉为原料，借助旋转粘度计研究了其非水基凝胶体系浆料的固化行为，以获得高质量的坯体。结果表明：引发剂用量、单体体积分数的增加以及固化反应温度的升高会使诱导期与反应期缩短；催化剂用量增加可以显著缩短诱导期时长，但对反应期的影响较小；与此相反，减小单体与交联剂体积比可以缩短反应期，但不改变诱导期的长短。结合浆料稳定性数据，通过调控引发剂及催化剂用量、固化反应温度、单体浓度和单体与交联剂体积比等影响因素，可以控制诱导时间在71~748 s、固化时间在154~714 s之间，从而实现不同尺寸要求和复杂程度产品的可控注模及固化。通过凝胶注模制备的多孔FeAl材料及制品孔隙结构均匀、开孔隙率为57.6 %、孔径小于10 μm、抗压强度可达40.7 MPa，满足烟气分离的需要。

Abstract:

With iron powder and aluminum powder as raw material, the rotating viscometer was used to measure the change of the viscosity of the slurry during the gelation process to investigate the gelation behavior to obtain high quality of the green body. The results show that: The increase of the initiator content, monomer content and reaction temperature will decrease both the idle time and the reaction time. The increase of catalyst content will significantly decrease the idle time while it has less impact on the reaction time. In turn, the reduction of the volume ratio of the monomer to the crosslinker reduces the reaction time, but has no influence on the idle time. Combined with the analysis of slurry stability, the idle time and reaction time can be control in range of 71~748 s and 154~714 s to realize the controllable gelation of products with different size and complexity by verifying the initiator content, the catalyst content, the reaction temperature, the monomer content and the volume ratio of the monomer to the crosslinker. the effects of these parameters on the idle time and reaction time has been systematically investigated. The controllable gelation can be realized by adjusting the idle time and the reaction time. Porous FeAl intermetallics with uniform pore structure, open porosity of 57.6 %, pore size below 10 μm, compressive strength of 40.7 MPa and complex shape fabricated by gel casting successfully match the demand of gas separation.