Iron microparticle deposition at high concentration

Abstract

PurposeDeposition of ink containing metal particles is possible using inkjet technologies. The purpose of this paper is to show a novel method for deposition of iron microparticles, with an average diameter of 1.24 μm, on a glass substrate that can potentially achieve concentrations of 0.21 per cent or higher.Design/methodology/approachThe method combines drop‐on‐demand (DOD) technology with a creative way of positioning iron microparticles near to the nozzle's print head. The use of ferromagnetic particles allows the control of particle dispersion on the target sample surface. The particles are positioned close to the nozzle using a sharpened steel rod as holder and their alignment is controlled by generating an external magnetic field along the sharpened steel rod.FindingsSuccessful deposition of iron microparticles with a potential concentration of 0.21 per cent or higher is reported.Research limitations/implicationsThe implemented method is restricted to ferromagnetic particles or alloys of ferromagnetic and non‐ferromagnetic materials.Practical implicationsThe method described could be integrated to control the deposition of iron microparticles in the production of optoelectronic devices and biosensors. This method speeds up the deposition process due to the higher metal microparticle concentrations achieved.Originality/valueThe deposition method introduced in the paper reached concentrations of 0.084 per cent, similar to the highest concentrations (0.1 per cent) reported with conventional methods (inkjet inks containing metal nanoparticles). It also prevents the blocking of the print head nozzles, thus improving the efficiency of Fe particle deposition.

Inkjet printing of magnetic materials with aligned anisotropy

“…Recent research shows that this technology has great potential in designing and producing magnetic materials. [1][2][3] "Magnetic ink," which is a dispersion of magnetic nanoparticles 1 or a solution composed of magnetic material precursors, 2 can be ejected by a drop-on-demand inkjet printhead onto almost any kind of substrate.…”

Composite Reinforcement Architectures: A Review of Field-Assisted Additive Manufacturing for Polymers

“…Field-assisted AM adopted from molding techniques have several advantages including the ability to produce functionally graded structures and optimized microstructures for specific functions and applications, such as in 4D printing-a manufacturing process involving multiple materials, and structures capable of transforming from one shape to another is known for using external fields or stimuli after the completion of print to induce shape changes, thus allowing custom reinforcement architecture in each layer [89][90][91]. Fine-tuning the position of reinforcement has led to the production of actuators and soft devices that can undergo programmed shape changes when triggered with an external stimulus (expansion and/or contraction) [53], self-healing capabilities in composites and electrical circuitry [35,92] improved conductivity in transparent thin films [93] and self-assembly of nanostructures [85,[93][94][95][96]. This has made AM a manufacturing process that allows the integration of controlled design synthesis methods to adjust corresponding manufacturability outcomes.…”

“…Their study mostly discussed the process of separating the magnetic droplet from the nozzle using an external magnetic field and no mechanical properties were tested [95]. Isaza et al also used DOD with a different approach with the assistance of a coil gun to print magnetic inks inside gaseous or liquid media, while possessing the ability to control droplet size, and hence, the resolution of the print [94].…”

Fully magnetic printing by generation of magnetic droplets on demand with a coilgun

“…[1][2][3] Materials science and engineering applications, including additive manufacturing (3D printing), require formation and printing of complex materials, magnetic in particular. [4][5][6][7][8][9][10] Since the beginning of the inkjet printing era, a long standing challenge of fully magnetic printing has been to break up magnetic fluids into droplets when the fluids are being pulled from a nozzle by a magnetic field. 11 It appears difficult to form droplets of magnetic fluids on demand by applying a magnetic field primarily because magnetic fluids always form a long liquid bridge connecting the drop with the nozzle.…”

“…Recently, interest on the printing of magnetic materials was rekindled by the opportunity to control the alignment of magnetic particles on the target. 4,6,10 It appears that by using available printheads, one can produce droplets of magnetic fluids on demand and then manipulate them with a magnet positioned close to the target. This way, magnetic particles could be aligned anisotropically in square and circular shaped magnetic films.…”