The mean grain size determination by ultrasonic velocity technique in basic boron carbide of ceramic metal composites

In this study, the mean grain size of ceramic-metal composites, made from boron carbide( B4 C )-aluminium (Al)-nickel (Ni) powders, has been determined with ultrasonic velocitytechnique by using 2 and 4 Mhz transducers. Samples were sintered at different temperaturesranging from 1200ºC to 1350ºC in Argon atmosphere. Ultrasonic velocity-grain size mastergraph was plotted using 4 Mhz ultrasonic transducer. The results were compared to the meangrain size obtained from SEM (Scanning Electron Microscopy) images. SEM (ScanningElectron Microscopy), EDX (Enerji Açılımlı X-ışını Spektrometresi) ve XRD (X-RayDiffraction) analysis are used after sintering process. . The production of ceramic metalcomposites using B4 C powders plated with Ni by electroless method were also attempted.In this work, the ceramic-metal composites were obtained by using Aliminium and Nickelwith boron carbide powders. In B4 C + Al composite sample was prepared by mixing %50B4 C and %50 Al, and in B4 C + Al + Ni composite samples were composed by mixing%50 B4 C , %25 Al and %25 Ni. Powders were placed in a 16,4 mm diameter mold andpressed using a hydraulic press at a pressure of 200 bar. Samples were sintered attemperatures of 1200ºC, 1300ºC and 1350ºC with Ar gas atmosphere in tube furnace.This work has shown the relation of ultrasonic velocity and average grain size of samples.Results shows that calculated and experimental mean grain size values have less than ~3,5 %difference. In Addition, we see that ultrasonic velocities of our composite samples areincreasing with average grain size of samples.Keywords: Material Characterization, Grain Size, Ultrasonic wave velocity, Boron Carbide