Characterization of brazed joints of CC composite to Cu-clad-Molybdenum

Abstract

Carbon-carbon composites with either pitch+CVI matrix or resin-derived matrix were joined to copper-clad molybdenum using two active braze alloys, Cusil-ABA (1.75% Ti) and Ticusil (4.5% Ti). The brazed joints revealed good interfacial bonding, preferential precipitation of Ti at the composite/braze interface, and a tendency toward de-lamination in resin-derived C-C composite due to its low inter-laminar shear strength. Extensive braze penetration of the inter-fiber channels in the pitch+CVI C-C composites was observed. The relatively low brazing temperatures (<950°C) precluded melting of the clad layer and restricted the redistribution of alloying elements but led to metallurgically sound composite joints. The Knoop microhardness (HK) distribution across the joint interfaces revealed sharp gradients at the Cu-clad-Mo/braze interface and higher hardness in Ticusil (~85-250 HK) than in Cusil-ABA (~50-150 HK). These C-C/Cu-clad-Mo joints with relatively low thermal resistance may be promising for thermal management applications.

Microstructure and mechanical properties of joints in sintered SiC fiber-bonded ceramics brazed with Ag–Cu–Ti alloy

“…Recently, active brazing of ceramic-matrix and carbon-carbon composites to themselves and to high-temperature metals by Ti-containing active braze alloys has been demonstrated [8][9][10][11][12]. In previous study [13], it was found that Ti-containing Ag-Cu active metal brazes generally were sound regardless of the type of ceramic-matrix composites being joined.…”

Integration of High‐Conductivity Graphite Foam to Metallic Systems Using Ag‐Cu‐Ti and Ag‐Cu‐Pd Braze Alloys

“…In recent years, light weight and high‐conductivity carbon–carbon composites and graphite foams have attracted a great deal of interest and attention for thermal management applications . Graphite foams offer low density, large surface area, high ligament and bulk conductivities, and chemical and thermal stability.…”

“…However, the high density of these materials (approximately 8450–9700 kg/m 3 ) has limited their use in lightweight thermal management applications. To reduce the component weight without sacrificing the thermal conductivity and thermal expansion benefits, Cu‐clad‐Mo has been joined to graphite and, more recently, to high‐conductivity C‐C composites, silicon nitride, and ultra‐high‐temperature ZrB 2 based composites …”

Interfacial reactions and zigzag groove strengthening of C/C composite and Rene N5 single crystal brazed joint

“…Although active metal brazing is a simple and cost-effective technique to join ceramics and C/C has been joined to Ti [4], TiAl [5], Cu [6][7][8], and Ni [9][10][11] based alloys by active vacuum brazing. However, joining of C/C with the nickel-based single crystal super alloy has seldom been reported.…”