Self-sustainable foaming process of porous aluminum

本研究旨在开发一种使多孔铝具有自持续发泡性能的新技术。下面的放热粉末反应被用作热源。采用钛+B_4C→TiB_2+ tic2 -碳化硼前驱体（B4C）进行自维持发泡。本研究主要考察了以下因素：研究表明，要实现自持续发泡过程，必须使用放热粉末。通过在前驱体中掺入TiH2，证明泡沫体的孔隙率有所提高。3 .多孔铝的孔隙率测定用阿基米德法测定了泡沫铝的孔隙率，并考察了工艺条件对泡沫铝孔隙率的影响。孔隙结构观察及孔隙形态评价采用图像分析软件对孔隙形态进行评价。与传统前驱体法制备的多孔铝相比，自持续发泡法制备的泡沫铝孔隙形态较为不规则。吹制过程中前驱体温度分布通过在前驱体中加入更多的钛粉来提高温度，可以有效地控制燃烧温度。同时加工制管/多孔铝集成件的研究采用该工艺制备了多孔铝与空心管之间的集成件。管道和泡沫之间的界面不足以实现化学粘合。

On this research, developing a new technology which enables a self-sustainable foaming behavior of porous aluminum was aimed at. The following exothermic powder reaction was used as a source of heat generation.Ti+B_4C→TiB_2+TiCThe precursor containing titanium and boron carbide (B4C) was used for self-sustaining foaming. The following factors were investigated in this research.1. Condition for enabling the self-sustaining foamingIt was revealed that the exothermic powders were necessary to realize the self-sustaining foaming process.2. Observation of the blowing behavior by exothermic reactionBy blending TiH2 in the precursor, the porosity of the foam was proved to be increased.3. Porosity measurement of porous aluminumThe porosity of the aluminum foam was measured by an Archimedes method, and the effect of processing conditions were investigated.4. Observation of the porous structure and evaluation of pore morphologyThe pore morphology was evaluated by an image analyzing software. The pore morphology of the foam fabricated by the self-sustainable foaming process was relatively irregular than the porous aluminum made by the conventional precursor process.5. Temperature profile of the precursor during blowing processIncreasing temperature by adding more titanium powder in the precursor was effective to control the combustion temperature.6. Investigation on the simultaneous processing for making pipe/porous Al integrated componentThe integrated component between porous aluminum and hollow pipe was fabricated by this process. The interface between pipe and foam was not sufficient enough to achieve a chemical bonding.