GÖZENEKLİ SERAMİK MALZEME İLE PASLANMAZ ÇELİĞİN DİFÜZYON KAYNAK YÖNTEMİYLE BİRLEŞTİRİLMESİ.

Metal/Ceramic joining technologies play a very important role in various aspects of the electronics and hightemperature component industries. Diffusion bonding is an advantageous technique for producing that type of joint since high-temperature mechanical resistance and defect-free interfaces can thus be achieved. However, one of the shortcomings of diffusion bonding is the high temperature needed for the bonding operation, which causes the development of high thermal stresses across the interface and fast growth of often undesirable reaction products. Usually, the residual stresses that originate from the metal are minimized by the addition of interlayer, which must be ductile and suitably reactive to both metal and ceramic in order to efficiently relieve the abovementioned thermal stresses. This study presents the weldability of the conventional stainless steel and prepared porous ceramic by diffusion welding. Different wetting materials (Ag, Cu and Ag-Cu-Ti alloy) with a thickness of about 100 µm were used with loading of 0.2 and 2 MPa pressures under vacuum-argon atmosphere and the applied temperatures were between 850, 875, and 900 °C for 45 minutes. The microstructure of metal-ceramic interface was investigated by scanning electron microscope (SEM) with EDS attachment for chemical analysis. The pores of the ceramic were filled with the Ag or its eutectic alloy through the interface with a thickness at about 40-60 µm. The joining mechanism of the stainless steel to ceramic was discussed with respect to diffusion and infiltration. [ABSTRACT FROM AUTHOR]