Micro-structural and Microhardness Study of Ni-Zn Ferrite Using Si Additive

Mixed Ni-Zn ferrites (x = 0.66, 0.77, 0.88, 0.99) were prepared by the double sintering ceramic method. Locally available low cost Fe2O3 with 0.5wt% of Si additive was used for this purpose to reduce the process price markedly and to improve the properties of the ferrite produced. Micro structural and micro hardness properties along with density and porosity have been investigated. Hardness increases with increase in metal contact, x of NixZn1-xFe2O4. SEM and optical micrograph shows very similar morphology of the particles with the amount of Si (0.5 wt %), must be low enough to prevent growth of large grains. © 2013 JSR Publications. ISSN: 2070-0237 (Print); 2070-0245 (Online). All rights reserved. doi: http://dx.doi.org/10.3329/jsr.v5i3.14467 J. Sci. Res. 5 (3), 415-420 (2013)

Micro and Macro Scratch and Microhardness Study of Biocompatible DLC and TiO2 Films Prepared by Laser

Mechanical properties of biocompatible diamond like carbon (DLC) and titanium dioxide (TiO2) films were tested using micro and macro methods. Microhardness was evaluated by AFM head and by Hysitron nanoindenter. Micro-hardness (H) from 27.0 GPa to 30.5 GPa (for DLC/Si) and from 11.7 GPa to 15.3 GPa (for DLC on Ti alloy) was measured. H for TiO2/Si was in range of 1.2 to 5.4 GPa. Macro Adhesion was tested by CSM Revetest. The critical force (FC) was from 6.5 to 13 N for DLC/Si resp. 3.5 to 10.8 N for DLC/Ti. For TiO2 the FC from 1 to more than 15 N was found. Micro adhesion was tested by AFM head and by Hysitron For DLC films the force FC from 4.3 to more than 75 mN resp. 1.1 to 1.5 mN and for TiO2.from 15 to 39 mN resp. 0.5 to 0.8 mN was achieved. Biocompatible DLC and TiO2 films were prepared by PLD on silicon or titanium alloy substrates. The advantage, disadvantage and comparison of methods and results obtained from micro and macro mechanical measurements are discussed.