TiH_2粉末模压成形剂优化研究

选择硬脂酸、十八醇、十八胺、金刚烷以及它们之间的混合物作为模压候选成形剂,以润滑粉体、润滑模具和同时润滑三种方式进行润滑,系统研究了它们对TiH_2粉体成形性的影响.结果表明,单纯TiH_2粉成形性非常差,添加成形剂能够显著改善粉体的成形性能.成形剂以第一种方式加入时,单一成分的成形剂很难达到相对密度较高和保形效果较佳的要求,而混合型即十八醇中添加少量金刚烷效果较好.采用润滑模具方式比较容易获得高质量压坯、成形剂用量少、压坯密度高、外观质量好.相比而言,同时润滑方式没有表现出明显的优势.研究还发现,压制压力是能否获得优质高密度压坯的关键因素之一,合理的TiH_2粉体压制压力范围为600～700MPa.

Research on the binder for TiH_2 powder die pressing

With Stearic acid、Octadecanol、Octadecyl amine、Adamantane and their intermixtures as candidate binders, the effect of candidate binders on the compactibility of TiH_2 powders was systematically studied and those binders were used in three ways: blending with TiH_2 powders, being coated on the surface of a pressing mold's cavity and simultaneously adopting the former two ways. The results show that though the compactibility of pure TiH_2 powders is too poor to obtain a fine compact, TiH_2 powders with binders can get better compactibility.In the first way intermixture binders show better compactibility than single one and among them a mixture of octadecanol with some of Adamantane is the best. It is revealed that in comparison with other two ways coating a binder on the surface of a pressing mold's cavity not only notably reduces binder dosage, but also insure to get a high quality green compact with higher relative density and better surface quality, but the third way shows little obvious advantage. Moreover, it is also found that pressing force plays a key role in fabricating a compact with high density and good geometry quality and a reasonable pressing force for TiH_2 powders is between 600-700MPa.