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CrN thin films are deposited on stainless steel (AISI-304) substrate using pulsed DC magnetron sputtering in a mixture of nitrogen and argon plasma. Two set of samples are prepared. The first set of sample is treated at different powers (100 W to 200 W) in a mixture of argon (95%) and nitrogen (5%). The second set of samples is treated at different nitrogen concentrations (5% to 20%) in argon (95% to 80%) for a constant power (150 W). X-ray diffraction (XRD) analysis exhibits the development of new phases related to different compounds. The crystallinity of CrN varies by varying the applied power and nitrogen content. Crystallite size and residual stresses of the CrN (111) plane show similar variation for the applied power and nitrogen contents. Scanning electron microscopy (SEM) analysis shows the formation of a granular surface morphology that varies with the change of powers and nitrogen content. The thickness of the film is measured using SEM cross sectional images and using atomic force microscopy (AFM) scratch analysis. The maximum film thickness (about 755 nm) is obtained for the film deposited at 5% nitrogen in 95% argon at 150 W power. For these conditions, maximum hardness is also observed.

Polycrystalline zirconium oxy-nitride (P-ZrON) composite films are deposited on Zr substrates by plasma focus device. The focusing efficiency of plasma focus is maximum at 1.5 mbar nitrogen pressure (NP) due to more intense signal of high voltage probe. The P-ZrON composite films are deposited for 25 focus shots at different NP. The XRD patterns confirm the evolution of ZrN (111), Zr 3 N 4 (230), Zr 3 N 4 (320), Zr 3 N 4 (140), Zr 3 N 4 (340) and ZrO 2 (200) diffraction planes. The peak intensity of different diffraction planes and their broadening are associated with increasing NP. The (N ? O)/Zr atomic ratio's are found to be 0.78, 0.88, 1.31, 0.66 and 0.55 at 0.5, 1.0, 1.5, 2.0 and 2.5 mbar NP respectively. The variation in crystallite size of different planes and strain transformation observed in various planes are attributed to varying ion energy fluxes which are associated with the increase of NP. The lattice parameter of ZrN is found to be 0.461 nm at 0.5 mbar NP which is decreased to 0.457 nm at 1.5 mbar NP. The weight fractions of ZrN, Zr 3 N 4 and ZrO 2 phases deposited at 2.5, 2 and 1.5 mbar NP are found to 30.5, 28.5 and 41 % respectively. The SEM microstructures reveal that the size and shape of nano-particles and the formation of complicated network of nano-wires (diameter = * 55 nm) and nano-combs are associated with increasing NP. The AFM images show the maximum rms surface roughness of P-ZrON composite film when deposited at 1.5 mbar NP. The micro-hardness (8623 ± 0.95 MPa) of P-ZrON composite film deposited at 1.5 mbar NP is found to be four times the micro-hardness of virgin Zr.

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Nano-crystalline tungsten nitride thin films are synthesized on AISI-304 steel at room temperature using Mather-type plasma focus system. The surface properties of the exposed substrate against different deposition shots are examined for crystal structure, surface morphology and mechanical properties using X-ray diffraction (XRD), atomic force microscope, field emission scanning electron microscope and nanoindenter. The XRD results show the growth of WN and WN 2 phases and the development of strain/stress in the deposited films by varying the number of deposition shots. Morphology of deposited films shows the significant change in the surface structure with different ion energy doses (number of deposition shots). Due to the effect of different ion energy doses, the strain/stress developed in the deposited film leads to an improvement of hardness of deposited films.

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Magnesium aluminate (MgAl2O4) commonly termed as spinel has been a subject of intense research due to its excellent thermal, optical and dielectric characteristics. These properties in such compounds can efficiently be tuned by introducing small contents of different transition metals. In this work, dilute contents of transition metals (Mn, Fe, Co, and Ni) are incorporated in MgAl2O4 to produce the dilute magnetic compositions of these aluminates. Crystallographic information reveals the formation of spinel cubic crystal structure with Fd−3m space group. Magnetic measurements demonstrate a clear magnetization response to an external magnetic field establishing dilute magnetic behavior of these spinels. The increase in ferroelectric characteristics with the incorporation of transition elements suggests that these materials are quite suitable for energy storage devices. A sharp variation in dielectric constant and magneto-dielectric coupling with the response to the external magnetic field, further exposes them as an excellent candidate for magneto-dielectric applications.