Structural, thermal and optical characteristics of Fe 1−X Zr X alloy by using mechanical milling approach: influence of Zr4+ ion

Abstract

By changing Zr concentrations, Fe _1-x -Zr _x (x = 0.25 & 1 at%) alloys were successfully produced in an argon atmosphere using the mechanical alloying method. The produced Fe _1-x -Zr _x alloys were characterized by x-ray diffraction (XRD), transmission electron microscopy (TEM), energy dispersion x-ray analysis (EDAX), fourier transform infrared spectroscopy (FTIR), thermogravimetry analyzer (TG-DTA), ultraviolet-visible spectroscopy (UV–vis) absorption, and photoluminescence (PL) spectroscopy. According to XRD pattern analysis, the prepared alloys had a cubic crystalline structure and complete solid solution formation. The prepared alloy samples the average crystallite size was calculated using the Scherrer formula. The average crystallite size for the 0.25 at% Zr concentration is found to be 7.79 nm and 11.8 nm for the 1 at% Zr concentration. Lattice parameter changes are a very important tool for confirming the complete dissolution of the Zr atom in the Fe matrix.The TEM-dark field image confirms that the grain size is in the nanometric range (<100 nm). TEM-SAED spotty continuous ring pattern confirmed the complete solution formation is well correlated with the XRD results. The elemental composition of materials can be determined quantitatively through energy dispersive x-ray analysis in the Fe _1-x -Zr _x alloy. The elemental distribution of the mechanically alloyed samples shows that Zr elements are homogeneously distributed in the Fe matrix. Bands at 3428 cm ^−1 in the FTIR spectrum have been linked to O–H stretching vibrations. CH _2 and CH stretching vibrations were associated with peaks of about 2920 cm ^−1 and 2850 cm ^−1 . The weight loss and gain changes were observed and represented in the TG-DST graph; we found that overall weight changes are + 10.7% (gain) at 1023 °C for Fe _1-x -Zr _x (x = 0.25 at%) alloy. However, when compared to 0.25 at% of Zr alloy, Fe-Zr (x = 1 at%) exhibits a low weight gain (+ 6.54%). The UV–visible absorbance edge revealed a blue shift when Zr was added, indicating alloy production. The energy band gap of materials was calculated using UV–vis, and it has been observed that the band gap reduces as Zr concentration increases. Zr was added to Fe _1-x -Zr _x alloy nanoparticles, resulting in 514 nm and 775 nm emission wavelengths. The greatest emission wavelengths and strong flawless sharp emission peaks were discovered to be between 450 nm and 550 nm. The higher PL emission peak was 514 nm at 0.25 at% of Zr.

Keywords

• Fe 1-x Zr x alloys
• mechanical alloying
• x-ray diffraction
• FTIR
• TEM