Nano TiN Particles Research Articles

Research on microstructure and properties enhancement of TiN/GH5188 Co-superalloy composite fabricated by laser powder bed fusion

Improving mechanical properties effectively in Laser Powder Bed Fusion (LPBF) is a substantial challenge. Utilizing metal matrix composites with customizable TiN nanoparticle proportions presents an efficient strategy for fabricating high-strength LPBF parts. This study employed LPBF to fabricate TiN/GH5188 Co-based superalloy composites with alternative TiN nanoparticle contents (0, 0.5, 1, and 1.5 wt%). The effect of nano-TiN particles on the microstructure, texture evolution, and mechanical properties of TiN/GH5188 composites was investigated. Notably, the presence of nano-TiN acts as a reinforcing particle, facilitating the precipitation of the BCC strengthening phase, resulting in substantial strength enhancement. As the TiN content increases, the yield strength and microhardness consistently rise. At a 1.5 wt% TiN addition, a significant enhancement is observed, with yield strength rising by 22.0 % and microhardness increasing by 16.9 %. Although the aggregation of TiN precipitates into larger particles reduces ductility, the appropriate addition of TiN can effectively mitigate the microstructural anisotropy and induce a transition in the texture toward a non-preferred orientation, while maintaining high strength and ductility. A TiN/GH5188 composite containing 1 wt% TiN exhibits a yield strength and tensile strength of 822.4 MPa and 1131.8 MPa, respectively, accompanied by a microhardness of 334.3 HV. The elongation remains at 29.3 %, while exhibiting a non-preferred orientation (111) texture. Compared to GH5188, the yield strength, tensile strength and microhardness are increased by 17.6 %, 7.2 % and 12.1 %, respectively. This study demonstrates the significance of LPBF in producing high-performance TiN/GH5188 Co-superalloy composites and elucidates the potential mechanisms of TiN in improving microstructure and enhancing properties.

Fabrication of Ni-TiN nanocomposite coatings by ultrasonic assisted jet electrodeposition

Ni-TiN composite coating is widely used as a protective coating due to its good mechanical properties and corrosion resistance. In this study, Ni-TiN nanocomposite coatings were prepared by ultrasonic-assisted jet electrodeposition. The growth mechanism and properties of the composite coatings in ultrasonic-assisted jet electrodeposition were studied. It was found that the surface morphology of the composite coating changed significantly with the increase in the concentration of nano TiN particles. Ultrasonic affects the selective orientation of the coating, and both lead to grain refinement. The addition of ultrasonic promotes the growth of (111) crystalline surfaces of the coating. Ultrasonic-assisted jet electrodeposition reduced tip discharge and nanoparticle agglomeration, and the surface quality, physical and chemical properties of the nanocomposite coating were significantly improved. The microhardness of the Ni-TiN composite coating was as high as 622.4 HV, the maximum adhesion was 27.2 N, and the corrosion resistance was the best with the corrosion current density at 1.898 μA cm−2, when the amount of nano TiN was 10 g/L. This method will provide a reference for improving the growth uniformity of jet electrodeposition.

Boosting Thermal and Mechanical Properties: Achieving High-Safety Separator Chemically Bonded with Nano TiN Particles for High Performance Lithium-Ion Batteries.

Currently, the commercial separator (Celgard2500) of lithium-ion batteries (LIBs) suffers from poor electrolyte affinity, mechanical property and thermal stability, which seriously affect the electrochemical performances and safety of LIBs. Here, the composite separators named PVDF-HFP/TiN for high-safety LIBs are synthesized. The integration of PVDF-HFP and TiN forms porous structure with a uniform and rich organic framework. TiN significantly improves the adsorption between PVDF-HFP and electrolyte, causing a higher electrolyte absorption rate (192%). Meanwhile, XPS results further demonstrate the tight link between PVDF-HFP and TiN due to the existence of TiF bond in PVDF-HFP/TiN, resulting in a strong impediment for the puncture of lithium dendrites as a result of the improved mechanical strengths. And PVDF-HFP/TiN can effectively suppress the growth of lithium dendrites by means of uniform lithium flux. In addition, the excellent heat resistance of TiN improves the thermal stability of PVDF-HFP/TiN. As a result, the LiFePO4 ||Li cells assembled PVDF-HFP/TiN-12 exhibit excellent specific capacity, rate performance, and capacity retention rate. Even the high specific capacity of 153 mAh g-1 can be obtained at the high temperature of 80°C. Meaningfully, a reliable modification strategy for the preparation of separators with high safety and electrochemical performance in LIBs is provided.

Effect of Magnesium Treatment on the Hot Ductility of Ti-Bearing Peritectic Steel

Surface cracking is a major defect in the production of continuous casting slabs of peritectic steel. The difference in crystal structure between δ phase (before peritectic transformation of steel) and γ phase (after peritectic transformation) results in volume contraction, which leads to uneven cooling of mold and thus forming slab shells with different thicknesses. Then, coupled with the concentration of local stress, surface cracking occurs on slabs. In this paper, the effect of magnesium treatment on the hot ductility of Ti-bearing peritectic steel was studied, and the characteristics of solidification structure and TiN particles were analyzed. Magnesium treatment for Ti-bearing peritectic steel could significantly improve the hot ductility of continuous casting slabs by refining the original austenite structure. After the magnesium treatment, the average grain size of the original austenite of peritectic steel decreased by about 18.7%, and the size of Mg-rich TiN particles decreased by about 41%. In addition, the minimum reduction of area at the third brittle zone after the magnesium treatment was higher than 60%, and the fracture appearance changed from intergranular fracture to ductile fracture after the treatment. The contents of Mg, Ti, O, and N in peritectic steel and the cooling conditions were adjusted reasonably to promote the formation of highly dispersed Mg-rich TiN particles with a sufficient number density and a proper size in the initial solidification stage of peritectic steel, so as to induce the high-temperature δ-ferrite nucleation. Based on the fine δ structure formed by peritectic transformation, through the use of structure heredity and the pinning effect of secondary-precipitated nano TiN particles on the austenite grain boundary, a fine and dense original austenite structure could be obtained to improve the hot ductility of peritectic steel. Industrial tests showed that through the magnesium treatment, the surface cracks of Ti-bearing peritectic steel were effectively restrained, and the corner cracks of slabs were basically eliminated.

Design of Hollow Nanosphere Structured Polypyrrole/Sn and SnO2 Nanoparticles by COP Approach for Enhanced Electron Transport Behavior

In this report, the Polypyrrole, PPy/Sn and PPy/SnO2 nanocomposites have been prepared through a facile chemical oxidation polymerization (COP) techniques. The resulting nanocomposites were characterized by Fourier transform-infrared spectroscopy (FT-IR), X-ray diffraction (XRD) and UV–Visible spectroscopy (UV–Vis). FTIR analysis confirms the presence of nano tin and SnO2 particles in the molecular structure. XRD patterns revealed that the sample is crystallite nature with tetragonal structure. The average crystallite size for the PPy/SnO2 and PPy/Sn nanocomposites are 27 and 56 nm. In addition to this, the surface morphologies and elemental compositions were investigated by field emission scanning electron microscopy (FESEM), high resolution transmission electron microscopy (HRTEM) and Energy-dispersive X-ray spectroscopy (EDX). We obtained the aggregate, hollow nanosphere for PPy/Sn nanocomposites. The results indicate that the hollow sphere of the nanocomposites effectively enhances the electrical conductivity.

The nickel based composite coating fabricated by pulse electroplating through graft between nano-TiN and graphene oxide

In the present study, inspired by the natural phenomenon of insects stuck by spider web, nano TiN particles were grafted onto graphene oxide (GO) with the help of polydopamine (PDA) by the reaction between amine in PDA and carboxyl in GO. The results of FTIR and XPS confirm that nano TiN particles are grafted onto GO successfully, which solves the dispersion problem of micro-content nano TiN particles in the fabrication of composite coatings by pulse electroplating. The introduction of nano TiN particles results in the grain refinement of the coating. Due to the synergistic effect of grain refinement and nano TiN particles, the hardness and wear resistance of the coating are enhanced successfully.

Grain refinement and localized amorphization of additively manufactured high-entropy alloy matrix composites reinforced by nano ceramic particles via selective-laser-melting/remelting

Abstract Nano TiN-particle reinforced CoCrFeMnNi high-entropy alloy (HEA) matrix composites were additively manufactured via selective laser melting (SLM) and that with a remelting laser-scan strategy (RLSS). The RLSS process promoted the reinforcement-dispersity and thus further refined the HEA matrix grains. The generated hybrid amorphous-crystalline microstructure was benefited by RLSS-SLM to enhance strength and regulate plasticity. The dispersion behaviors and effects of nano TiN-particles were expounded. The amorphous formation mechanism was also discussed.

Selective laser melting of CoCrFeNiMn high entropy alloy powder modified with nano-TiN particles for additive manufacturing and strength enhancement: Process, particle behavior and effects

Selective Laser Melting (SLM) was applied for Additive Manufacturing (AM) of CoCrFeNiMn high entropy alloy (HEA) and TiNp/CoCrFeNiMn composite, with the tailored laser parameters for as-printed bulk densification after the process optimization. The pre-alloyed HEA powder by gas-atomization was modified with nano-TiN ceramic particles on the powder surface layer and employed to fabricate HEA matrix composite with uniformly dispersed TiN reinforcements via SLM. The hierarchical microstructures with strong crystallographic textures were generated in the as-printed HEA parts. While in the TiNp/HEA composite, the remarkably refined and nearly equiaxial HEA matrix grains were produced due to the contribution of introduced TiN particles. The average ultimate tensile strength (σUTS) of as-printed composite achieved 1036 MPa with the average elongation to fracture (ef) as ~12%. By contrast, the average σUTS and ef of as-printed HEA were 601 MPa and ~30% respectively. The strengthening mechanism of the SLM-fabricated TiNp/HEA composite was further elucidated.

Study on a Ni-P-nano TiN composite coating for significantly improving the service life of copper alloy synchronizer rings

Ni-P-nano TiN composite coatings were successfully prepared and used on the TL084 copper alloy synchronizer ring by electroless plating. The bench test on copper alloy synchronizer rings with the optimal processing indicates a service life as high as 2 × 105 cycles with sufficient friction coefficient, far exceeding the engineering requirements. Scanning electron microscope (SEM), energy dispersive spectrometer (EDS) and X-ray diffractometer (XRD) were employed to characterize morphology, composition, structure and phase transformation behavior of the nano-composite coatings. Variations in hardness and wear resistance induced by the addition of various amounts of nano TiN particles were also investigated and correlated with microstructural characteristics. Compared with conventional pure Ni-P coatings, remarkable increases in hardness and wear resistance were observed in the nano-composite coatings, which can be ascribed to the nano TiN particles uniformly distributed in the Ni-P matrix. The introduction of TiN nanoparticles into the electroless Ni-P coating does not significantly affect the structure before and after the heat treatment, but can enhance the hardness.

Enhanced thermoelectric figure of merit of Co4Sb11.5Te0.5 via a two-pronged strategy combining grain refinement and nano-inclusions

In this study, a strategy combining grain refinement and nano-inclusion is presented to enhance the thermoelectric figure of merit (ZT) of Co4Sb11.5Te0.5. Homogeneously dispersed nano-TiN particles are introduced into the different grain-size skutterudite compounds Co4Sb11.5Te0.5 through ball milling and spark plasma sintering. The phase purity, microstructures, and thermoelectric properties of all the samples are characterized. The results prove that the sample consisted of the finest grain (∼220 nm) Co4Sb11.5Te0.5 and nano-TiN demonstrates a much lower thermal conductivity of 2.34 Wm−1 K−1 at room temperature and a highest ZT value of 1.07 at 800 K. Furthermore, annealing this sample at 500 °C for 50 h shows minor changes in structure and ZT value, indicating an excellent thermal stability.

Grain refining mechanism in pure aluminum with nanosized TiN/Ti composite refiner addition

A composite TiN/Ti grain refiner for aluminum and its alloys was prepared through a mixture of micro sized metal powder Ti and nanosized ceramic particles TiN by high energy ball milling. Refinement performance of the TiN/Ti refiner in pure aluminum has been examined in detail by OM, FSEM, EBSD, DSC and TEM methods. Experimental findings indicate that, after adding 0.5 wt% TiN/Ti, the solidification structure of pure aluminum can be refined and the preponderant grain size is reduced to 79.8 μm from more than 1000 μm. TiN/Ti significantly refines the aluminum grain size through not only that it makes undercooling be not measured and increase the nucleation temperature from 671 °C to 681 °C, but also the introduction of potent nuclei. Furthermore, nano TiN particles can act as the nucleus of heterogeneous nucleation of α(Al), the α(Al) grows along the {111} crystal plane from {200} surface of TiN, “Ti-rich transition region” surrounding TiN particles and the heat of reaction between Al and Ti enhances the wettability of TiN in the melt.

Sulphate Doped Polypyrrole Encapsulated Tin Composite for the Lithium Ion Battery Anode

Tin is considered as a promising candidate for the lithium ion anode which is synthesized by co-precipitation technique using stabilizing agents such as C-TAB. The conducting Sn-sulphate doped polypyrrole is synthesized by polymerization of pyrrole monomers in the nano tin particles dispersed in 0.1% PVP + water medium using ammonium per sulphates as a polymerizing as well as doping agent. The XRD, SEM and TEM analysis confirms the formation of polypyrrole coated on tin nano particles to form a composite. Pulverization effect of tin metal electrode is the highly significant challenge to solve while charge-discharge process, thus while lithium insertion and desertion process the polymer based conductive material like polypyrrole (conductive polymer) coated on tin nano particle holds the active material to avoid isolation from the conductive matrix, which act as a current collector. The coating thickness is being optimized by the various weight ratios of polymer to tin nano particles from 5 to 20%. The thickness of the coating is analyzed by SEM and TEM; the electrochemical behavior is investigated by EIS and charge-discharge studies. 80:20 ratio of tin-polypyrrole composite gives almost 100% capacity retention at the rate 400 mA g-1 and delivers initial specific discharge capacity of 878 mAh g-1 Figure 1

Study on Dispersion and Rheology of Particles in Water-Based Nano TiN Fluid

The water-based nanoTiN fluids were prepared by nanoTiN particles, dispersion medium and dispersant using a two-step method. The dispersion and rheology of nanoparticles in water-based fluid were studied under different preparation conditions. The dispersion and rheology of prepared nanoTiN fluids were evaluated and analyzed from the mass fraction of nanoparticles, mass fraction of dispersant and type of dispersion medium respectively by using the analysis of sedimentation stability and rheological properties. The results show that the above-mentioned factors all have different degree of influence on nanofluids’ dispersion and rheology. The viscosity of nanofluids increases with mass fraction of nanoparticles. A balance amount of mass fraction of dispersant will improve nanofluids’ dispersity and fluidity. The dispersion effect of deionized water is the best when the nanoparticles dispersed in different dispersion medium.

Surface modification of nano-TiN by using silane coupling agent

Abstract Titanium nitride (TiN) nano-particles were subjected to graft modification by silane coupling agent (KH-570) via a direct blending method. The hydroxyl groups on the surface of TiN nano-particles can interact with silanol groups [-Si-OCH3] of KH-570 forming an organic coating layer. The covalent bonds (Ti-O-Si) formation was testified by Fourier transform infrared spectra (FTIR) and X-ray photoelectron spectroscopy (XPS). Through transmission electron micrograph (TEM) observations, it was found that KH-570 could improve the dispersibility of nano-TiN particles in ethyl acetate. Thermo gravimetric analysis (TGA) and contact angle measurements indicated that KH-570 molecules were adsorbed or anchored on the surface of nano-TiN particle and the net efficiency of it was 22.76 %, which facilitated to hinder the aggregation of nano-TiN particles.

The surface modification of TiN nano-particles using macromolecular coupling agents, and their resulting dispersibility

Titanium nitride (TiN) nano-particles were modified by the grafting of a random copolymerization functionalized macromolecular coupling agent (F-MCA) via a direct blending method. The hydroxyl groups on the surface of the nano-TiN particles interact with the silanol groups [SiOCH3] of the F-MCA to form an organic coating layer. The formation of covalent bonds [TiOSi] was verified using Fourier transform infrared spectroscopy. An X-ray diffraction analysis suggests that the presence of the F-MCA inhibited the growth of the crystal plane but did not change the crystal structure of the TiN. Thermogravimetric analysis and contact angle measurement indicated that the F-MCA molecules were adsorbed or anchored to the surface of the nano-TiN particles, which hindered their aggregation. Pristine nano-TiN particles are poorly dispersed in ethyl acetate. Compared with the pristine TiN particles, the modified TiN particles show good dispersibility and form a stable colloidal dispersion in ethyl acetate. The surface hydrophobicity of the modified TiN increases, and the F-MCA molecules are anchored on the surface of the TiN particles. TiN particles modified by a F-MCA can be used in polymer blends, thermoplastic elastomers and polymer nanocomposites that have a better performance and longer life cycle.

The TiN Content Computer Prediction Based on ANN and AR Model

Artificial Neural Network (ANN) and autoregressive model (AR model) of nano TiN particles content in Ni-TiN composite coating was established by the method of time series analysis. In this paper, we want to seek for the TiN content computer prediction in Ni-TiN composite coatings by using ANN and AR model. The trend of the nano TiN particles content variation was forecasted with the AR model, and the prediction value and experimental test results were compared. The XRD patterns were investigated using X-ray Diffraction (XRD).The results show the number of the neuron in hidden layers is 10, and the optimal epoch is 3740. The ANN and AR model can forecast the nano TiN particles content in Ni-TiN composite coating. And the average deviation is about 5.2884%. The average grain size for Ni and TiN is approximately 52.85 and 39.13 nm, respectively.

On Surface Modification of Nano-TiN with Graft Copolymer LMPB-g-KH570

Nano-TiN were modified by the macromolecular coupling agent (LMPB-g-KH570), a graft copolymer of KH570 and LMPB in dimethylbenzene. The graft copolymer's molecular structure was confirmed by FTIR and NMR, and its average molecular weight was measured by VPO. The Mn value of LMPB-g-KH570 was calculated as 4025.058, meeting the requirement that optimum number-averaged molecular weight should be in the range of 3000–10000. The graft copolymer LMPB-g-KH570 was used for the surface modification of nano-TiN. The surface properties and thermal stability of modified nano-TiN were investigated by FTIR, TGA, TEM, contact angle, and surface free energy measurement. The results showed that the macromolecular coupling agent bonds covalently onto the surface of nano-TiN particles and forms an organic coating layer. TGA and contact angle measurement indicated that LMPB-g-KH570 molecules were absorbed or anchored on the surface of nano-TiN and its using efficiency is 67.35%, which facilitates to hinder the aggregation of nano-TiN. TEM results also revealed that modified nano-TiN possesses good dispersibility.

Prediction of Nano TiN Particles Content in the Ni-TiN Composite Coating Based on AR Model

Auto Regressive model (AR) of nanoTiN particles content in Ni-TiN composite coating was established by the method of Time Series Analysis. The trend of the nanoTiN particles content variation was forecasted with the AR model,and the prediction value and experimental test results were compared. The results show the model may forecast the nanoTiN particles content in Ni-TiN composite coating. And the average deviation is about 5.2884%. The average grain size for Ni and TiN is approximately 52.85 and 39.13 nm, respectively.

Study on the Preparation of TiN Nano-Particles in a Solidified Low Alloy Steel

By using vacuum melting, nitrogen protection and a high molten flow rate during pouring, many nano-TiN particles with the size of 20~100nm are formed during solidification of the alloy steel composed of C0.12- Si0.24 - Mo0.45 - Cr0.35 - V0.2 - Ti0.29 (wt.%). In addition, there are 0.9-1.4μm micron-sized particles separated by a space of 15~40μm. Precipitable TiN particles greatly refine the microstructure of the alloy steel. In this paper, the thermodynamic, kinetic mechanisms and related factors of TiN formation are analyzed.

Effect of nano-TiN particles on microstructure and mechanical properties of Si3N4-based nanoceramics

Effect of nano-TiN particles on the microstructure and mechanical properties of Si3N4 based cearmics were investigated. The nanocomposites were fabricated by hot pressing Si3N4 and TiN nanopowders. The main phases in nanocomposites were α-Si3N4, β-Si3N4, Si2N2O and TiN. Proper addition of TiN nanoparticles can significantly increase the flexural strength and the fracture toughness. The maximum values of the fracture toughness and the flexural strength were obtained when the content of TiN particles was 10 and 15 wt-% respectively. The hardness of the nanocomposite slightly decreased with the addition of nano-TiN particles. The main strengthening and toughening mechanisms are the crack tip bridging and the crack deflection by TiN particles.