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Metal-alumina joints have found various practical applications in electronic devices and high technology industry. However, making of sound metal ceramic brazed couple is still a challenge in terms of its direct application in the industry. In this work we successfully braze copper with Al₂O₃ ceramic using Zr_52.5Cu_17.9Ni_14.6Al₁₀Ti₅ bulk metallic glass forming alloy as filler alloy. The shear strength of the joints can reach 140 MPa, and the microstructrural analysis confirms a reliable chemical boning of the interface. The results show that the bulk metallic glass forming alloys with high concentration of active elements are prospective for using as filler alloy in metal-ceramic bonding.

This study has analyzed the welding joint of carbon fiber reinforced plastics (CFRP) and aluminum alloys. The surface of CFRP and 5083 Al alloy was modified by electroplating with nickel at first. Then the effect of electroplating parameters on coating was explored. SEM images revealed that the coating gradually became well but then began to fall off with the current density and the plating time increased. CFRP and aluminum alloys were brazed at 285${}^{\circ }$C and held for 20 s. Shear test was used to evaluate the strength of the joint and the strength was probably 7.56 MPa. SEM and EDS tests showed that there existed diffusion of the elements in the welding process and the joint reached the bonding of atomic or molecular sizes. Thus, this experiment achieved the tight brazing joining between thermoset CFRP and aluminum alloys providing the joining method of the application for CFRP.

Brazing experiments between tungsten and MA956 ODS steel were conducted at $41050^{\circ }\mathrm{\text{C}}$ with different holding time to investigate the interface microstructure evolution and mechanical properties of the brazed joints. The interface microstructures were analyzed by the scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD), and the mechanical properties of the joints were measured to find the optimal brazing parameter. The results show that tungsten and MA956 steel has been successfully joined by brazing. The intermetallic compound of Ni–W formed at the W/BNi-2 interface, which was detrimental to the strength of the joint. Due to the excellent mutual solubility between Fe and Ni, no new formed intermetallic compound was found at MA956-brazing filler interface. The shear strength of the brazed joints with BNi-2 filler reached 246 MPa at the optimal brazing parameter $1050^{\circ }\mathrm{\text{C}}/20\mathrm{\text{min}}$.

In this study, Carbon–Carbon (C–C) composite joints were prepared using BNi-1a paste filler metal as the intermediate layer in a vacuum brazing method. The interfacial structures and compositions of the joints were analyzed using scanning electron microscopy (SEM), energy dispersive spectrometry (EDS) and X-ray diffraction (XRD). The results show that element interdiffusion and chemical reactions occurred in the joining zone, and various compounds were formed, including Cr₃C₂, Ni₃₁Si₁₂, Ni(_s.s), MB and MC ((M = Cr, Fe, Ni). The optimum joining parameters were determined to be the brazing at the temperature of 1120^∘C for 60 min, which produced the joint with the maximum shear strength of 24.13 MPa. The joint shear strength and fracture morphology demonstrate that bonding temperature and retention time have a significant effect on the strength of C–C composites.

The promising role of structural ceramics in many useful devices and structures has in turn led to realization of the importance of developing ceramic joining techniques, which is perhaps one of the most important areas in the ceramic field for research and development. The increasing demand for joining ceramics arises from: a) fabrication of ceramic components of complicated shape or large size in one piece can be very expensive and in some cases impractical, and b) in many cases, because of the limitation of ceramics resulting from poor impact properties and lack of tensile ductility they have to be attached to metals, which must withstand stresses or temperature gradients too great for ceramics. This paper covers methods and problems of joining of ceramics with emphasis on brazing technique. This also includes examples of joining silicon nitride ceramic to itself and to molybdenum.

The study is concerned with developing a low-melting-point filler metal for brazing 3003 aluminum alloys. For this purpose, a series of designed Al-Si-Cu-Zn-Mn filler metals were prepared and evaluated in the light of melting characteristics and spreading area. Al-25Cu-7.5Si-5Zn-1Mn alloy was picked out as contrasting filler. Based on the orthogonal test, the composition of Al-20Cu-7.5Si-10Zn-1Mn filler metal was then optimized. Its solidus and liquidus temperatures of 454.0 °C and 521.9 °C were lower than those of the contrasting filler, and the spread ability was slightly better. The mechanical properties, micro structure and fracture morphology of the joints brazed for 20 min by the two types of filler metal were investigated subsequently. The results showed that the shear strength of the joint brazed with the optimized filler was higher in the brazing temperature range of 540-580 °C, compared to Al-25Cu-7.5Si-5Zn-1Mn filler. The maximum strength was obtained at the brazing temperature of 570 °C, being 70.8 MPa. The fracture surface located in the central brazed layer and was characterized by the mix of local ductility and main cleavage, which is favorable to improve the joint strength.