公开(公告)号：US5707568A

公开(公告)日：1998-01-13

申请号：US456832

申请日：1989-12-18

申请人： David Charles Deleeuw ,  Jonathan Lipowitz ,  Paul Pu-yuan Lu ,  James Alan Rabe

发明人： David Charles Deleeuw ,  Jonathan Lipowitz ,  Paul Pu-yuan Lu ,  James Alan Rabe

IPC分类号： C03C13/06 ,  C04B35/571 ,  D01F9/10 ,  C01B31/00 ,  C04B35/56

CPC分类号： C04B35/571 ,  C03C13/06 ,  D01F9/10

摘要： A process for the preparation of substantially polycrystalline silicon carbide fibers is provided. The fibers may be fabricated to have a small diameter and are thermally stable at high temperatures. The process is carried out by initially forming fibers from a preceramic polymeric precursor comprising methylpolysilane resins. The fibers are then infusibilized to render them nonmelting followed by a pyrolysis step in which the fibers are heated to a temperature in excess of 1600.degree. C. in a nonoxidizing atmosphere to form substantially polycrystalline silicon carbide fibers. The substantially polycrystalline silicon carbide fibers which are formed by the process of the present invention have at least 75% crystallinity and have a density of at least about 2.9 gm/cm.sup.3. The polymeric precursor or the fibers contain, or have incorporated therein, at least about 0.2% by weight boron. This incorporation of boron may be accomplished either prior to or during formation of the fibers or during at least one of the infusibilizing or pyrolyzing steps of the process.

摘要翻译： 提供了制备基本上多晶碳化硅纤维的方法。 纤维可以制造成具有小直径并且在高温下是热稳定的。 该方法通过由包含甲基聚硅烷树脂的预陶瓷聚合物前体初始形成纤维来进行。 然后将纤维熔融以使其不熔化，随后进行热解步骤，其中将纤维在非氧化气氛中加热至超过1600℃的温度以形成基本上多晶的碳化硅纤维。 通过本发明的方法形成的基本上多晶的碳化硅纤维具有至少75％的结晶度并且具有至少约2.9gm / cm 3的密度。 聚合物前体或纤维含有至少约0.2重量％的硼或其中并入其中。 这种硼的掺入可以在纤维形成之前或期间或在该方法的至少一个不熔化或热解步骤期间完成。