Research On The Process And Properties Of Alumina Ceramic And TC4 Brazed Joint

Alumina ceramic has the advantages of light weight, high strength, heat resistance, wear resistance, corrosion resistance, anti-radiation, etc. However, alumina ceramic have the defects of high brittleness, low toughness and difficult to process, require connect with metal which have good plasticity in application. In this paper, we selected brazing to realize the connection of alumina ceramic and TC4 alloy. TC4' diffusion to the brazing seam was utilized to provide active element participating in the forming of metal reaction layer.In this paper, we use non-reactive Ag-Cu solder in the brazing of Al₂O₃ ceramics and TC4 alloy. Typical interface structure Al₂O₃/Ti3Cu3O/Ag?s,s?+Cu?s,s?+ Ti-Cu+Ti-Al/TC4 were got in the braze joints. By changing the content, adding form of brazing filler and changing the brazing temperature and holding time, we can achieve brazing joint with good performance. We research the organization and mechanical properties of the joints using SEM, EDS and XRD, the mechanical properties of joints was achieved by shear test. The connection mechanism of non-active Ag-Cu Crystal solder and the source of the active element in the brazing seam were analyzed. The physical model of brazing joint' forming process was established' dissolve into the brazing seam and the composition and formation mechanism was analyzed. We also investigate the influence of process parameters on the interface organization and mechanical properties of the joints.It can be drawn out that when B element was added in the non-active Ag-Cu crystal filler, TiB was formed in the brazing seam. There is an optimum value of the content of B element, brazing temperature and holding time to get the best joints. When joining B content is 0.2%, brazing temperature is 880 ?, holding time is 10 min, the shear strength can be more than 200 MPa.