Thermomagnetic characterization of organic-based ferrofluids prepared with Ni ferrite nanoparticles

• Published in: Materials science & engineering. B, Solid-state materials for advanced technology Vol. 215; pp. 1 - 8
• Main Authors: Arana, Mercedes, Bercoff, Paula G., Jacobo, Silvia E.
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 01.01.2017; Elsevier BV
• Subjects: Agglomerates; Ball milling; Conductivity; Diffusivity; Ferrites; Ferrofluid; Ferrofluids; Heat transfer; High-energy ball-milling; Kerosene; Magnetic fields; Nanoparticles; Ni-ferrite; Specific heat; Thermal conductivity; Thermomagnetic properties; Ferrofluid; Thermal conductivity; Ni-ferrite; High-energy ball-milling; Diffusivity; Thermomagnetic properties
• ISSN: 0921-5107; 1873-4944
• DOI: 10.1016/j.mseb.2016.10.006

[Display omitted] •Kerosene-based ferrofluids of Ni-ferrite NPs from high energy ball milling.•Thermomagnetic characterization of organic-based ferrofluids.•Measured thermal variables enhancements of ferrofluid vs. magnetic field.•Curves successfully fitted by a gas-compression model of nanoaggregates. In this work, a thermomagnetic characterization of kerosene-based ferrofluids (FFs) prepared with Ni-ferrite nanoparticles (NPs) is performed by measuring their thermal conductivity and diffusivity coefficient enhancements. The particles were synthesized by high-energy ball milling, as an alternative to the most commonly chosen NPs synthesis methods for FFs. The action of an applied magnetic field on the FF increases the thermal conductivity and diffusivity due to cooperation between the NPs, as it agglomerates them favoring chain-like and clusters formations. It was found that the heat capacity of the studied FFs decreases under the application of a magnetic field. The obtained results for thermal conductivity of FFs under magnetic fields were fitted by a gas-compression model that considers NPs agglomerates in the fluid.