Study the effect of the sintering temperature on the microstructure and optical reflectance of the compacted bulk CuAlS2 fabricated by powder metallurgy technique (P/M)

In this work, the effect of the sintering temperature of the bulk compacted powder sample on the microstructure and reflectance of the bulk CuAlS₂, which fabricated by powder metallurgy [P/M] technique, has been studied. The bulk was produced by [P/M] at compacting pressure of 350 MPa, sintering time 2 hr and different sintering temperature (100, 150, 200, 250 and 300°C). X-ray diffraction [XRD], scanning electron microscopy [SEM], energy dispersive analysis [EDS], and optical reflectance measurements were used for characterization of the prepared samples. The analysis of X-ray diffraction [XRD] indicated a formation of CuAlS₂ phase with preferring orientations of [1 1 2], [2 0 0], [2 2 0] and [0 0 8]. The intensity of CuAlS₂ phase continuously increases with increasing the sintering temperature. It has been observed that the crystallite size increases with increasing of the sintering temperature from 24.25 nm at 100°C to 31.33 nm at 300°C, giving an indication of enhancement in the crystallinity. The analysis of [SEM] indicated the treated surface morphology of the bulk CuAlS₂. An increase in crystallization and formation of the CuAlS₂ phase was observed with increasing the sintering temperature. The cluster size shows remarkable rise with the increase of sintering temperature which confirms improvement in grain growth. The optical data shows, that with increasing the sintering temperature the reflectance decreased to 15% at 200°C in the near of infrared region [NIR] and 10% at 200°C and 250°C in the visible region [VIS].

Keywords: CuAlS2, Optical Reflectance, Powder Metallurgy, Sintering Temperature