公开(公告)号：US20180319711A1

公开(公告)日：2018-11-08

申请号：US15586390

申请日：2017-05-04

Applicant: General Electric Company

Inventor： Anthony Yu-Chung KU ,  Xi YANG ,  Tao LI ,  John Patrick POLLINGER ,  Zachary Kenneth MOWRY ,  Frederic Joseph KLUG

IPC: C04B35/185 ,  B28B1/24 ,  B28B11/24 ,  B28B13/06 ,  C04B35/64

CPC classification number: C04B35/185 ,  B28B1/24 ,  B28B7/42 ,  B28B11/243 ,  C04B35/64 ,  C04B41/0072 ,  C04B41/009 ,  C04B41/80 ,  C04B2111/0087 ,  C04B2111/00939 ,  C04B2235/3217 ,  C04B2235/483 ,  C04B2235/6567 ,  C04B2235/6581 ,  C04B2235/662 ,  C04B2235/75 ,  C04B2235/80 ,  C04B2235/9669 ,  C04B2235/9676 ,  C22C27/04 ,  C04B41/4515 ,  C04B41/4519 ,  C04B41/4556

Abstract: Methods for forming ceramic cores are disclosed. A ceramic core formed using the method of the present application includes a silica depletion zone encapsulating an inner zone. The inner zone includes mullite and the silica depletion zone includes alumina. The method includes heat-treating a ceramic body in a non-oxidizing atmospheric condition for an effective temperature and time combination at a pressure less than 10′ atmosphere to form the silica depletion zone at a surface of the ceramic core.