Mixed Oxide Materials for Helium Leak Tight, Oxidation Resistant and High Strength Joints Between High Temperature Engineering Materials

Abstract

A high strength joint material. A material for a joint between a ceramic body and a metal body. A material for a joint between a ceramic body and a ceramic body.

1 . A high strength joint material consisting essentially of alumina (99.8% purity), silica (99.99% purity) and magnesia (99+% purity) with or without additions collectively of less than 4 wt % of TiO2, Fe2O3, CaO, NaO2, K2O, P2O5 and sintering aid materials. 
     
     
         2 . The high strength joint material of  claim 1 , further comprising a mixed oxide material selected from the group consisting of Magnesium Silicate and Aluminum Silicate. 
     
     
         3 . The high strength joint material of  claim 1 , further comprising a mixed oxide material selected from the group consisting of Steatite® and Mulcoa®. 
     
     
         4 . The high strength joint material of  claim 1 , further comprising a mixed oxide material selected from the group consisting of Steatite® and Lava. 
     
     
         5 . The high strength joint material of  claim 1 , further comprising a mixed oxide material selected from the group consisting of Steatite® and Wonder Stone®. 
     
     
         6 . The high strength joint material of  claim 1 , wherein the joint material provides oxidation resistance at a temperature between 400° C. and 1500° C. 
     
     
         7 . The high strength joint material of  claim 1 , wherein the joint material joins one of ceramic-to-ceramic, ceramic-to-metal and metal-to-metal. 
     
     
         8 . The high strength joint material of  claim 1 , wherein the joint material has a coefficient of thermal expansion between 1.5×10-6/K and 5×10-6/K at a room temperature. 
     
     
         9 . The high strength joint material of  claim 1 , wherein the joint material forms a hermetic joint between similar or dissimilar materials when the similar or dissimilar materials to be joined have a coefficient of thermal expansion between 1.5×10-6/K and 5×10-6/K, wherein the hermetic joint is defined by an ability to seal to less than 1×10-9 torr.-L./sec. helium leak rate. 
     
     
         10 . The high strength joint material of  claim 9 , wherein the hermetic joint between the dissimilar materials with a coefficient of thermal expansion mismatch when each of the dissimilar materials to be joined has a coefficient of thermal expansion between 1.5×10-5/K and 5×10-6 /K. 
     
     
         11 . A material for a joint between a ceramic body and a metal body comprising:
 between 30 wt % (weight percent or percent by mass) and 80 wt %, nominally 60 wt %, aluminum-silicate, and between 20 wt % and 70 wt %, nominally 40 wt %, magnesium-silicate.   
     
     
         12 . A material for a joint between a ceramic body and a metal body comprising:
 between 16.8 wt % and 35.8 wt %, nominally 28.2 wt %, alumina, between 57.9 wt % and 61.2 wt %, nominally 59.2 wt %, silica and between 6.3 wt % and 22.0 wt %, nominally 12.6 wt %, magnesia.   
     
     
         13 . A material for a joint between a ceramic body and a ceramic body comprising:
 between 30 wt % (weight percent or percent by mass) and 80 wt %, nominally 60 wt %, aluminum-silicate, and between 20 wt % and 70 wt %, magnesium-silicate.