Development and construction of AISI H11/ZrO2 joints for injection molding tools

Increasing demands in industrial applications and simultaneous efforts to provide long-lasting and cost-efficient tools in the injection molding industry lead to the use of metal–ceramic joints with the aim to combine the specific properties of both materials. Due to its high CTE, zirconium oxide (ZrO 2 ) is used for the ceramic part and is joined with the tool steel AISI H11 (1.2343). In this work, suitable joining techniques with a low heat input and therefore a low thermal load are applied and characterized for the production of metal–ceramic composites. The selection of joining techniques is based on the boundary conditions during the injection molding process, in which the composites have to resist the temperature, pressure, as well as shear and tensile loads. Therefore, besides brazing, other joining processes such as gluing, screwing, shrinking, and clamping were analyzed as possible low temperature joining techniques for ceramic-metal-compounds. The best results for the tensile strengths with 90 MPa were achieved by a brazing process, carried out in vacuum with approximately 10 −5 mbar, at a temperature of 920 °C for 5 min, using the commercially available brazing filler alloy CB4.