Laser sintering of separated and uniformly distributed multiwall carbon nanotubes integrated iron nanocomposites

Abstract

Uniform distribution of carbon nanotubes (CNTs) in metal matrix during additive manufacturing of nanocomposites is always a challenge since the CNTs tend to aggregate in the molten pool. In this study, Multiwall carbon nanotubes (MWNTs) were separated and distributed uniformly into iron matrix by laser sintering process. MWNTs and iron powders were mixed together by magnetic stir, coated on steel 4140 surface, followed by laser sintering. Due to the fast heating and cooling rate, the CNTs are evenly distributed in the metal matrix. The temperature field was calculated by multiphysics simulation considering size effects, including size dependent melting temperature, thermal conductivity, and heat capacity. The SEM, TEM, and XRD were used to understand the laser sintering of CNT integrated nanocomposites. The results proved the feasibility of this technique to synthesize MWNTS integrated metal matrix nanocomposites. V

Super-strengthening and stabilizing with carbon nanotube harnessed high density nanotwins in metals by shock loading

“…1a . multi-wall nanotubes (MWNTs) are integrated into iron matrix by laser sintering (LS) 6 , followed by laser shock peening (LSP) process. Molecular dynamics simulation reveals the high local stress built up around CNT/metal interface, thus enables formations of high density nanotwins.…”

Direct Ink Writing Technology (3D Printing) of Graphene-Based Ceramic Nanocomposites: A Review

“…The final properties of polymer nanocomposites crucially depend on the effectiveness of the nanoparticle dispersion process [233]. Thus, a good nanofillers dispersion in the polymer will produce a maximum increase in the properties of the composite [234][235][236][237]. In many studies, the process of preparing composites has been taken into account to obtain a high homogeneity and dispersion of graphene-based materials within a polymer matrix [238].…”

Pulsed Laser Cladding of NiCrBSiFeC Hardcoatings Using Single-Walled Carbon Nanotube Additives

“…Generally, two distinct mechanisms are responsible for this improvement, depending on the nature of the metal matrix: (1) the carbonaceous nanomaterials react with the metal phase in a molten state, generating carbides with high hardness [12,16], or (2) they do not dissolve into the metal phase, providing, in turn, mechanical strengthening, either through load transfer effect, through refinement of metal grains (the CNTs are located at the grain boundaries), or through interaction with dislocations at the atomic level [7,17]. The former mechanism was reported for titanium [12,15], aluminium-copper alloys [18], and silicon-rich metal alloys [19], while the latter was reported, for example, in the case of mild steel [20], pure iron [21], nickel [14], aluminium [22,23], magnesium [8], and copper [9,24,25]. When embedded in the metal, good interfacial adhesion between CNT and the metal phase has been observed, due to the formation of a thin intermediary layer of metal carbide on the nanomaterial surface, avoiding delamination [26].…”

“…Most studies about laser-cladded metal-CNT coatings have been conducted on nonferrous metal powders and substrates (mainly based on copper, aluminium, and titanium) [27,29]. Comparatively, nickel and iron-based coatings reinforced with CNTs, in conjunction with steel substrates, bearing a higher application potential than nonferrous coatings, have attracted considerably less attention, due to their relatively high susceptibility to embrittling and cracking [2,21]. Therefore, the aims and elements of novelty of this study are to demonstrate the feasibility of the pulsed laser cladding method to obtain nickel-based hardcoatings on a mild steel substrate, starting from a preplaced commercial NiCrBSiFeC powder, mechanically blended with single-walled carbon nanotubes (SWCNTs), and to assess the effects of nanotube addition on the morphology, microstructure, hardness, hard phase composition, tribological properties, and corrosion resistance of the obtained assembly.…”