新型陶瓷注射成形喂料催化脱脂过程的研究

Research on Catalytic Debinding of a Novel Ceramic Injection Molding Feedstock

陶瓷注射成形是一种受到日益广泛关注的技术 ,但其中脱脂一步传统采用的热脱脂技术脱脂速度慢 ,效率较低。本研究采用以聚甲醛为主要粘结剂制备了可快速脱脂的新型陶瓷注射成形喂料体系 ,并进行催化脱脂工艺的研究 ,记录了该过程中样品失重的情况 ,分析了脱脂阶段不同特征及其原因 ,指出催化脱脂过程速度的控制因素是气态催化剂和气体产物扩散过程。通过脱脂前后样品表面及截断面的扫描电镜分析 ,直观反映了脱脂前后样品微观形貌上的差异及特点。观察了脱脂过程不同时刻样品外围与中心区域的微观形貌 ,证明了脱脂过程是由外围逐渐向内部扩散的 ;

In this paper,a new technology known as catalytic debinding was adopted at a temperature lower than the melt temperature of hte main binder,and the whole process could be finished in ten hours or so.The binder is composed of polyoxymethylene(POM) as main binder and polyethylene(PE) as a secondary binder,oxialic acid as catalyst.The weight\|loss process of samplers was recorded,and the three typical stages in debinding process were also analyzed,it was concluded that the controlling factors of the process are the diffusions of the gaseous catalyst and decomposition yield.Scanning electron microscope(SEM) was used in the research to carry out the morphology study of the samples'cross\|sections before and after debinding.SEM photos of the outer and inner areas of hte samples were also taken to show that the catalytic debinding process is advanced gradually form the periphery to the center.Densities of the samples before and after sintering were also studied as the basic property of the feedstock.