Nano and Micron Raw Materials for Manufacturing 2D and 3D Advanced Materials: Physical Form, Dispersion, Loading, Direct and Indirect Routes, and Qualification

The industrial use of nano-and micron-scale powders, fibres, platelets and dispersions requires more than matching a material name to an additive-manufacturing category. Raw-material identity includes composition, crystalline or molecular state, primary dimensions, morphology, aspect ratio, specific surface area, porosity, surface chemistry, coating, moisture, aggregation, agglomeration, contamination, ageing and package history. Each attribute can change when a sample is split, dispersed for measurement, compounded into a feedstock, pumped, jetted, extruded, recoated, irradiated, cured, dried, debound, sintered or finished. This qualitative engineering review defines a complete chain from supplier lot to accepted 2D trace, coating, retained 3D composite, green body, sintered material or indirectly moulded component. It explains why number-, area-, volume-and intensity-weighted size distributions answer different questions; why dynamic light scattering, laser diffraction, microscopy and gas adsorption are not interchangeable; why zeta potential is a conditional indicator rather than a universal stability certificate; and why a deagglomeration process must be controlled by delivered energy, temperature, contamination and damage as well as mixing time. Process-specific sections examine vat photopolymerisation, direct ink writing, material jetting, material extrusion, powder-bed routes, films and patterned 2D structures. A route-selection framework distinguishes retained fillers from materials intended to become the continuous final phase after binder removal, and it compares direct shaping with printed-mould and precursor routes. Primary studies in ceramic stereolithography, silica-glass nanocomposites, colloidal and nanoparticle inks, fibre-filled extrusion, magnetically oriented platelets, rotational printing, conductive polymer composites and laser-assisted metal writing are used to expose mechanisms without transferring their recipes. The review concludes that the qualifying unit is not the named powder or even the formulated feedstock, but the complete material–interface–process–transformation–product state. A nano/micron route should proceed only when representative identity, dispersion state, processability, exposure control, final composition, microstructure, function, ageing and change control can all be demonstrated for the intended geometry and factory.