Deformation and cracking during sintering of bimaterial components processed from ceramic and metal powder mixes. Part I: Experimental investigation

Parts composed of two ceramic–metal composite layers have been fabricated by co-sintering of two powder blends. The major constituent was the ceramic powder in one blend and the metal powder in the second one. This paper focuses on the mechanical analysis of the co-sintering process. This process has been observed thanks to an original optical dilatometry set up that provided images of the component in the course of sintering cycle. These images allowed following component shape changes throughout the thermal cycle and also evidenced the formation of cracks at the edges of a part at particular stages of the sintering cycle. These phenomena are interpreted from the mismatch between the densification kinetics of each powder blend sintered alone. In a companion paper the results of a finite element simulation of cosintering are compared to the experimental data displayed in the present paper.

► Continuous observation of the sintering of a bilayer powder compact.
► Comparison of the strains in the bilayer with those measured during free sintering.
► Detection of crack formation at the edges of the larger component during heating.
► Deformation and cracking are explained with regard to strain mismatch.