Disclosed herein is a method comprising disposing a container containing a metal and/or ferromagnetic solid and abrasive particles in a static magnetic field; where the container is surrounded by an induction coil; activating the induction coil with an electrical current, to heat up the metallic or ferromagnetic solid to form a fluid; generating sonic energy to produce acoustic cavitation and abrasion between the abrasive particles and the container; and producing nanoparticles that comprise elements from the container, the metal and/or the ferromagnetic solid and the abrasive particles. Disclosed herein too is a composition comprising first metal or a first ceramic; and particles comprising carbides and/or nitrides dispersed therein. Disclosed herein too is a composition comprising nanoparticles comprising chromium carbide, iron carbide, nickel carbide, y.-Fe and magnesium nitride.

This invention provides a multifunctional magnetic composition that can be used in applications such as slimebots and sensors. In one embodiment, said composition, comprises: a) 0.005-5 wt. % of a source of tetrafunctional borate ions; b) a buffer for maintaining pH at 6.5 to 9.5; c) 0.005-80 wt. % of magnetic particles; and d) a polymeric glue having hydroxyl groups; wherein said tetrafunctional borate ion, buffer and magnetic particles are crosslinked in said polymeric glue to form a non-Newtonian fluid composition.

A magnetorheological fluid includes: a metal magnetic particle having a surface modified with an ionic liquid modifying site having a first cationic group and a first anionic group; and an ionic liquid dispersion medium having a second cationic group and a second anionic group, in which the first cationic group and the second cationic group are same kind of cation and are selected from the group including a quaternary ammonium ion, an imidazolium ion, a pyridinium ion, and a phosphonium ion, and the first anionic group and the second anionic group are each selected from the group including a tetrafluoroborate ion, a hexafluorophosphate ion, a trispentafluoroethyl trifluorophosphate ion, a bis(trifluoromethanesulfonyl)amide ion, a hydrogen phthalate ion, and a bisfluorosulfuryl imide ion.