Out-of-Furnace Brazing Technology for Assembly of Large Carbon-Carbon Space Structures.
Abstract
In this Phase I SBIR program, Foster-Miller demonstrated the feasibility of an innovative joining technique for two-dimensional carbon/carbon (C/C) composite materials using active braze alloys. Traditionally, brazing of C/C composites required use of high- temperature vacuum furnaces. Vacuum brazing required expensive capital equipment with a limited working area and brazing cycles on the order of several hours to more than a day. The Foster-Miller technique utilized a controlled atmosphere induction brazing to reduce the brazing times to minutes and increased the interlaminar strengths by using of the proprietary Foster-Miller z-pin reinforcement technique. The use of the out-of-furnace brazing concept combined with z-direction reinforcements showed strengths of up to 1550 psi compared to the vacuum furnace braze joint strengths of 1153 psi. The constituents of the purging gases as well as proprietary solid oxygen getters were adjusted to eliminate all oxygen while brazing, thus minimizing problems associated with oxidation. This program analyzed the advantages of the oxygen getters in addition to the effect of braze layer thicknesses on strengths of the brazed C/C joints. The follow-on Phase II program will focus on transitioning the brazing technology to aerospace and terrestrial thermal management and structural applications of C/C composites.
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 01, 1994
- Accession Number
- ADB205552
Entities
People
- G. Freitas
- S. Khatri