Ceramic materials can be directly brazed to metals by using the so-called active brazing alloys. [1] In general these alloys are obtained by modifying conventional brazing fillers by adding an element able to promote wetting of the ceramic surface (typically a group IV element). One of the most common solutions is the addition of Ti to eutectic or quasi-eutectic AgCu or to AgCuIn alloys (In is added to improve the wetting behavior and lower the brazing temperature). The use of AgCuTi and AgCuTiIn for the production of ceramic-metal joints is widely reported in literature, typically for joining Si 3 N 4 , but also other ceramics. For instance Incusil™ABA ® (Ag 59 Cu 27.25 In 12.5 Ti 1.25 , WESGO ® , Erlangen, Germany) is used for various ceramic-metal combinations [2][3][4] while a Ag 71.5 Cu 19.5 In 5 Ti 3 alloy is utilized to braze AlN to different metals. [5] Given the materials to be joined and the joint geometry, there are two main issues affecting the mechanical performance of a ceramic-metal joint: the bond quality, which depends the ability of the filler to wet the ceramic surface, and the residual stresses which develop in the assembly after brazing (due to the differences in the mechanical and thermal expansion characteristics of the two joining partners) and primarily depend on the plastic deformation of the filler. The quantity of the active element in the brazing alloy has a two-fold influence on the joint performance: on one hand a large amount ensures better wetting, on the other it would lead to hardening of the filler alloy, detrimental to residual stress relief. [6] Moreover a low content of active element is generally preferred when brazing ceramics to reactive metals, such as steel, because an excess of active element could promote undesirable reactions (e.g. the formation of brittle intermetallic phases). The optimization of the content of active element in the alloy is crucial for successful brazing of ceramic-steel joints.In the present work a Ag 61.5 Cu 23.5 In 15 alloy (Incusil™15, WESGO ® , Erlangen, Germany) was modified by adding Ti in different amounts: 0.5, 1.0 and 1.5 wt.%. The considered active element weight fractions are typical of commercial active brazing fillers used in ceramic-steel joints. Bulk specimens of Incusil™15 and Incusil™15-Ti were fabricated and micro-hardness measurements were carried out to study the effect of Ti addition on the plastic properties of the alloy. The microstructure was investigated by optical and electron microscopy and by image analysis techniques. The alloys were used to braze Si 3 N 4 /TiN to steel and the joint performance was assessed by four point bend tests. The results of hardness measurements confirm that Ti has a hardening effect on Incusil™15. However, for the considered values of Ti addition (0.5 -1.5 wt.%), experimental results indicate that the extent of the hardening is insignificantly influenced by the amount of Ti introduced in the alloy. This was confirmed by the results of four point bend tests on joints which showed that sample...