Investigation of the mechanical machinability of an interpenetrating metal-ceramic composite using diamond grinding

Abstract In this study, the mechanical machinability of an interpenetrating metal-ceramic composite was investigated. The material was manufactured by gas pressure infiltration of a slurry-based ceramic preform and an AlSi10Mg cast alloy. The combination of a soft metal and a very hard ceramic brings many advantages in mechanical performance of the composite but challenges in the mechanical machining. Near net shape components manufactured and finished by mechanical processing is of interest. Therefore, diamond-grinding with different diamond grit tipped tools was investigated in a range of process parameters, such as the rotation speed, feed rate, and cutting depth. During the grinding process, the cutting forces were continuously measured, and the machined surface and tool quality were evaluated afterwards. Cold welding of the aluminum chips on the tool and the material surface were detected, and the effect of the superposition of ductile and brittle cutting mechanisms were observed. Increasing cutting forces and therefore increasing the process heat results in reclosing of brittle defects in Al 2 O 3 by deformed aluminum. This effect leads to a reduced surface roughness when increasing the material removal rate by increasing cutting speed, feed rate, and cutting depth.