TiN Particles Research Articles

Microstructures and properties of AlZnMgCu alloys refined by nano Al3Ti-TiB2-AlN-TiN/Al inoculant ribbons.

Nano Al3Ti-TiB2-AlN-TiN/Al inoculant ribbons containing a large number of evenly distributed nanoparticles, such as Al3Ti (sized about 300nm), TiB2 (sized about 100nm), AlN (sized about 150nm), and TiN (sized about 200nm), were prepared by vacuum rapid quenching furnace to refine AlZnMgCu alloys. The nano Al3Ti-TiB2-AlN-TiN/Al inoculant ribbons showed an excellent inoculant effect, which modified the dendrite crystals to equiaxed crystals and refined the grains from 122 ± 4µm to 36 ± 5µm by the addition of 0.3 wt% nano Al3Ti-TiB2-AlN-TiN/Al inoculant ribbons. In addition to nano Al3Ti and TiB2 particles, nano AlN and TiN particles also have a certain orientation relationship with α-Al, which suggests that these particles possess nucleation potency to α-Al. After inoculation with 0.3% nano Al3Ti-TiB2-AlN-TiN/Al inoculant ribbons, the ultimate tensile strength, yield strength, and average microhardness of the AlZnMgCu alloys increased from 246MPa, 79MPa, and 112 HV to 319MPa, 100MPa, and 136 HV, or by 29.7%, 26.6% and 21.4%, respectively.

Titanium nitride@nitrogen-doped carbon nanocage composites as high-performance cathodes for aqueous Zn-ion hybrid supercapacitors

Aqueous Zn-ion hybrid supercapacitors (AZHSCs) pertain to a new type of electrochemical energy storage device that has received considerable attention. They integrate the advantages of high-energy Zn-ion batteries and high-power supercapacitors to meet the demand for low-cost, long-term durability, and high safety. Nevertheless, the challenge caused by the finite ion adsorption/desorption capacity of carbon electrodes gravely limits their energy densities. This work describes titanium nitride@nitrogen-doped carbon nanocage (TiN@NCNC) composite cathodes for AZHSCs to achieve a greatly improved energy density, and the composites can be facilely synthesized based on the calcination of a mixture of tetrabutyl titanate and zeolitic imidazolate framework-8 in argon atmosphere. The resulting composites are featured by the ultra-fine TiN particles dispersed uniformly on the NCNC surfaces, enhancing the Zn2+ storage capabilities. Using TiN@NCNC cathodes, the AZHSCs can operate stably with a high energy density of 154 Wh kg−1 at a specific power of 270 W kg−1 and achieve a remarkable capacity retention of 88.9 % after 104 cycles at 5 A g−1. At an extreme specific power of 8.7 kW kg−1, the AZHSCs can retain an energy density of 97.2 Wh kg−1. With these results, we stress that the TiN@NCNC cathodes render high-performance AZHSCs and the facile one-pot method can easily be scaled up, which enables AZHSCs a new energy-storage component for managing intermitted renewable energy sources.

Microstructure and wear property of (TiN + NbC) double ceramic phase-reinforced in FeCrNiCoAl high-entropy alloy coating fabricated by laser cladding

This study delves into the influence of TiN and NbC ceramic particles on the phase structure, grain organization, microhardness, and wear resistance of FeCoNiCrAl High-Entropy Alloy (HEA) composite coatings produced through laser cladding. The integration of ceramic particles induced a dual BCC solid-solution phase structure (B2+BCC), with the formation of a TiNb phase upon the melting and interaction of TiN and NbC in the melt pool. The ceramic particles significantly modified the grain structure of the HEA coatings, disrupting the Columnar-to-Equiaxed Transition (CET) and favoring the emergence of equiaxed grains. The TiN particles induced a substantial refinement of grain size, albeit unevenly, while NbC had a milder effect. The combined presence of TiN and NbC particles resulted in a more uniform grain refinement, enhancing the mechanical properties of the coatings. Notably, the (TiN + NbC)/HEAs composite coating demonstrated superior mechanical performance under the synergistic effect of both ceramic particles. The average microhardness value increased by 55.80 % compared to 17-4Ph stainless steel, and the wear rate was reduced by 88.38 %, with the wear mechanism primarily involving abrasive and oxidative wear.

Ejection of molten tin in the presence of a hydrogen plasma

One of the significant obstacles left if the development of a fusion power plant is the development of Plasma Facing Components (PFCs) that can withstand the large heat and particle flux incident on the first wall and divertor region. As solid PFCs struggle with microstructure growth, sputtering and melting, liquid metals have been a popular potential replacement. Liquid metal's use as a PFC has been increasing due to its ability to self-repair damage as well as pump lost fuel and waste particles to create a low recycling edge. Currently, tin, lithium and lithium eutectics are the commonly considered liquid metals for use as a fusion PFC. It is therefore important to research the Plasma Material Interaction (PMI) between a hydrogen plasma and the liquid metal PFC candidates. This work, conducted at the Center for Plasma Material Interaction (CPMI), investigated how a molten tin surface reacts when exposed to a hydrogen plasma, building off observations by ASML of particles being ejected from a molten tin surface in the presence of a hydrogen plasma. With the ejection of tin affecting ASML's systems as well, since ejected tin can travel around their systems and cause contamination of equipment or wafers that can be destructive to the lithography process. So, for this work, molten tin was exposed to a hydrogen plasma, of varying electron densities and temperatures, and any ejected particles were collected on a witness plate to determine the particle sizes, angular distribution and mass flux. This work found the ejected tin particles range in size from 10′s ofnms to 10′s of microns and that the mass flux of tin from the molten surface is in the 10′s of mgm2*s, increasing with increased atomic hydrogen flux to the molten tin surface. Showing macroscopic amounts of molten tin are ejected in the presence of a hydrogen plasma, therefore showing tin may not be a suitable fusion PFC material.

Microstructure and Wear Resistance of In Situ Synthesized Ti(C, N) Ceramic-Reinforced Nickel-Based Coatings by Laser Cladding.

In recent years, laser cladding technology has been widely used in surface modification of titanium alloys. To improve the wear resistance of titanium alloys, ceramic-reinforced nickel-based composite coatings were prepared on a TC4 alloy substrateusing coaxial powder feeding laser cladding technology. Ti (C, N) ceramic was synthesized in situ by laser cladding by adding different contents (10%, 20%, 30%, and 40%) of TiN, pure Ti powder, graphite, and In625 powder. Thisestudy showed that small TiN particles were decomposed and directly formed the Ti (C, N) phase, while large TiN particles were not completely decomposed. The in situ synthetic TiCxN1-x phase was formed around the large TiN particles. With the increase in the proportion of powder addition, the wear volume of the coating shows a decreasing trend, and the wear resistance of the surface coating is improving. The friction coefficient of the sample with 40% TiN, pure Ti powder, and graphite powder is 0.829 times that of the substrate. The wear volume is 0.145 times that of the substrate. The reason for this is that with the increase in TiN, Ti, and graphite in the powder, there are more ceramic phases in the cladding layer, and the hard phases such as TiC, Ti(C, N) and Ti2Ni play the role in the structure of the "backbone", inhibit the damage caused by micro-cutting, and impede the movement of the tearing point of incision, so that the coating has a higher abrasion resistance.

Die steel design for additive manufacturing

A novel printable die steel was computationally designed and experiemtnally validated for selective laser melting (SLM), utilizing the advantages of the rapid solidification processes. During gas atomization, nanoscale TiN particles are intended to be insitu precipitated at 1790°C, nucleating δ-ferritic grains. Additionally, the chemical composition is adjusted to stabilize a complete δ-ferritic solidification via Scheil modeling to enhance the printability of the die steel. This work further introduces the concept of the matrix die steels aiming to dissolve solidification and primary carbides during solutionizing at a targeted temperature of 1100°C. Thus, the C-content is reduced to 1.4 mol.-% (0.3 wt.-%) compared to the benchmark H13 die steel with which contains 1.85 mol.-% (0.4 wt.-%). Even though a lower C-content is used, optimizing M2C driving force during tempering enables the die steel to achieve a peak hardness of 536 HV is achieved. Lastly, a superior thermal conductivity of 40 W m-1 K-1 is predicted at 450°C for the BCC matrix of the printable matrix die steel. The material design is based on thermo-chemical models interfaced with thermodynamic calculations as implemented in the Calculated Phase Diagram (CALPHAD) method.

Refinement of cast microstructure of A517 steel by addition of TiB2

AbstractThe effect of TiB2 addition on microstructure refinement of the as-cast and reheated A517 steel has been investigated. 0.1 wt.% TiB2 addition resulted in a reduction in equiaxed γ grain size from 990 ± 183 to 116 ± 35 μm and an increase in the volume fraction of equiaxed γ grain region from 5% to 67% in the as-cast A517 steel ingots. Microstructure analysis identified TiN particles rather than TiB2. This is attributed to the low thermodynamic stability of TiB2, leading to its decomposition into free Ti and B elements at an elevated temperature. Then, chemical reaction between the free Ti and residual nitrogen in the liquid resulted in the formation of TiN. Hence, it is considered that TiN acted as heterogeneous nucleation sites for the δ-ferrite. This initiated the refinement and columnar to equiaxed transition of δ-dendrites. As a result, the subsequently formed γ grains were correspondingly refined. Such microstructure refinement led to improvement of the yield strength and ultimate tensile strength of the as-cast A517 steel. However, the reheating of the as-cast A517 steel resulted in a marginal microstructure refinement in the samples with low TiB2 addition. This is attributed to the limited pinning effect of the coarse TiN particles formed during casting process. Consequently, the tensile properties of the reheated A517 steel remained unaffected by the TiB2 addition.

Volcanic Eruption in the Nanoworld: Efficient Oxygen Exchange at the Si/SnO2 Interface.

Here, a phenomenon of efficient oxygen exchange between a silicon surface and a thin layer of tin dioxide during chemical vapor deposition is presented, which leads to a unique Sn:SiO2 layer. Under thermodynamic conditions in the temperature range of 725-735°C, the formation of nanostructures with volcano-like shapes in "active" and "dormant" states are observed. Extensive characterization techniques, such as electron microscopy, X-ray diffraction, synchrotron radiation-based X-ray photoelectron, and X-ray absorption near-edge structure spectroscopy, are applied to study the formation. The mechanism is related to the oxygen retraction between tin(IV) oxide and silicon surface, leading to the thermodynamically unstable tin(II)oxide, which is immediately disproportionate to metallic Sn and SnO2 localized in the SiO2 matrix. The diffusion of metallic tin in the amorphous silicon oxide matrix leads to larger agglomerates of nanoparticles, which is similar to the formation of a magma chamber during the natural volcanic processes followed by magma eruption, which here is associated with the formation of depressions on the surface filled with metallic tin particles. This new effect contributes a new approach to the formation of functional composites but also inspires the development of unique Sn:SiO2 nanostructures for diverse application scenarios, such as thermal energy storage.

Submicrometer Particle Impact Dynamics and Chemistry.

Experimental studies of the collision phenomena of submicrometer particles is a developing field. This review examines the range of phenomena that can be observed with new experimental approaches. The primary focus is on single-particle impact studies enabled by charge detection mass spectrometry (CDMS) implemented using the Aerosol Impact Spectrometer (AIS) at the University of California, San Diego. The AIS combines electrospray ionization, aerodynamic lens techniques, CDMS, and an electrostatic linear accelerator to study the dynamics of particle impact over a wide range of incident velocities. The AIS has been used for single-particle impact experiments on positively charged particles of diverse composition, including polystyrene latex spheres, tin particles, and ice grains, over a wide range of impact velocities. Detection schemes based on induced charge measurements and time-of-flight mass spectrometry have enabled measurements of the impact inelasticity through the determination of the coefficient of restitution, measurements of the angular distributions of scattered submicrometer particles, and the chemical composition and dissociation of solute molecules in hypervelocity ice grain impacts.

Peculiarities in XPS spectra of Sn/SiO2 layers as an effect of surface charge

X-ray photoelectron spectroscopy based on synchrotron radiation was used to investigate the composition of the observed SnO2-x/Sn:SiO2-x thin layer grown by organometallic chemical vapour deposition on single-crystalline silicon wafer with additional argon ions etching treatment. Due to the formation of a thermodynamic anomaly during in situ layer growth, an efficient oxygen exchange between silicon and tin oxide phases occurs. The present study addresses the effect of localized surface charging and its influence on the obtained XPS core level spectra. We found that due to the high electrical conductivity of metallic tin and the direct coupling of tin particles to the silicon wafer, the XPS Sn 3d5/2 core level spectrum is not affected by the surface charge compared to the highly charged dielectric silicon oxide matrix, as observed for the XPS O 1 s and Si 2p core level spectra. Our results show that the core level spectra of Si 2p and O 1 s are shifted up to 3 eV due to the presence of uncompensated positive charge on the surface of the silica matrix. These results provide insight into the influence of surface charge effects on the analysis of conductor/insulator composite materials and contribute to the application of Sn-based materials in various application concepts related to energy and surface functionalization.

Enhanced wear resistance of Ni-Mo-TiN composite coating by synergistic effect of tough Ni-Mo matrix and hard TiN particles

To improve the wear resistance of the metallic components, Ni–Mo-TiN composite coating was prepared via pulsed electrodeposition. The microstructure, mechanical, and tribological characteristics were compared to those of Ni–Mo coating. The results revealed that the addition of TiN reduced internal stress within the Ni-Mo-TiN composite coating and mitigated the propensity for crack formation during both the coating preparation and friction testing. Grooves and pits are observed on the Ni-Mo coating, indicating a typical feature of fatigue wear. Owing to the synergistic effect of the tough Ni-Mo matrix and hard TiN particles, the Ni-Mo-TiN coating was characterized by micro-cutting and superior wear resistance. Based on the experimental results, the effects of TiN on the microstructure, mechanical properties, and wear resistance of the Ni-Mo coating were discussed.

Influence mechanism of solution temperature on microstructure evolution and tensile properties of Ti microalloyed high strength steel CGLC700

The influence mechanism of solution temperature on the strength and toughness of Ti microalloyed steel CGLC700 was studied. The microstructure changes of Ti microalloyed steel were observed by micro-electron microscopy, and the mechanical properties were evaluated by tensile test. The appropriate solution temperature can promote the solid solution of Ti atoms and the formation of small-sized TiN, TiC and other particles, hinder the movement of dislocations, and improve the tensile properties of steel. When the solution temperature is 1240 °C (2#), the grain size of steel is the lowest, the proportion of high angle grain boundary is the highest, and the tensile properties of steel are the best. Ti microalloyed steels increased tensile strength by 4.12%, yield strength by 2.85% and elongation by 28.4%. Too low or too high solid solution temperatures weaken the strengthening effect of the microalloying elements and led to a reduction in the tensile properties of the steel. This can be attributed to the low solid solution of Ti at low solid solution temperatures and the growth of second phase particles and inclusions at too high solid solution temperatures. This study provides a theoretical basis for optimizing the heat treatment process of Ti microalloyed steel.

Synthesis and Characterization of Titanium Nitride-Carbon Composites and Their Use in Lithium-Ion Batteries.

This work focuses on the synthesis of titanium nitride-carbon (TiN-carbon) composites by the thermal decomposition of a titanyl phthalocyanine (TiN(TD)) precursor into TiN. The synthesis of TiN was also performed using the sol-gel method (TiN(SG)) of an alkoxide/urea. The structure and morphology of the TiN-carbon and its precursors were characterized by XRD, FTIR, SEM, TEM, EDS, and XPS. The FTIR results confirmed the presence of the titanium phthalocyanine (TiOPC) complex, while the XRD data corroborated the decomposition of TiOPC into TiN. The resultant TiN exhibited a cubic structure with the FM3-M lattice, aligning with the crystal system of the synthesized TiN via the alkoxide route. The XPS results indicated that the particles synthesized from the thermal decomposition of TiOPC resulted in the formation of TiN-carbon composites. The TiN particles were present as clusters of small spherical particles within the carbon matrix, displaying a porous sponge-like morphology. The proposed thermal decomposition method resulted in the formation of metal nitride composites with high carbon content, which were used as anodes for Li-ion half cells. The TiN-carbon composite anode showed a good specific capacity after 100 cycles at a current density of 100 mAg-1.

Titanium nitride induced wide temperature range self-lubricating silicon nitride ceramics with low wear and stable low friction coefficient

Silicon nitride (Si3N4) with excellent mechanical properties and chemical stability, has been widely used in many fields. However, wear failure is often the cause of the short life of Si3N4 devices at high temperatures, thereby the wear resistance of Si3N4 ceramics still needs to be further improved. In this work, titanium nitride is used as a reinforcing phase to prepare wear-resistance Si3N4 ceramics in a wide temperature range by spark plasma sintering. The effect of TiN particles on densification process, phase transformation, mechanical properties, and tribological properties in wide temperature range from 25 to 800 °C were tested and analyzed. At room temperature, TiN particles hindered the propagation of microcracks, and the wear rate was reduced by an order of magnitude, reaching 3.69×10−6 mm3·N−1·m−1. At 800 °C, the completed TiO2 oxide film exhibited self-repairing and lubricating properties, which further reduced the wear rate to 9.35×10−7 mm3·N−1·m−1. Additionally, the friction coefficient of Si3N4 ceramics with 30 vol% TiN decreased considerably and remained stable in the wide temperature range of 25 ∼ 800 °C, with a range of 0.69 ∼ 0.85.

Investigation of the microstructural evolution and mechanical properties of bimodal TiN-reinforced 316L stainless steel composite fabricated by SLM

ABSTRACT Selective Laser Melting (SLM) preparation of TiN-reinforced 316L stainless steel effectively addresses the weaknesses of 316L stainless steel in terms of strength and hardness. While ensuring the flowability of the composite powder, this study employs dual-sized TiN particles to enhance 316L stainless steel. Experimental results indicate that micrometre-sized TiN particles are embedded in the matrix, and other TiN particles dissolve and re-form into cubic TiN particles with a diameter of around 200 nm. Samples produced at high laser energy density exhibit high density, consistently above 99%. The average grain size of the austenite is refined to 2.38 μm, and the tensile samples with a 90° interlayer rotation angle and island size of 60 × 10mm2 exhibit a maximum yield strength of 661 MPa, ultimate tensile strength of 950 MPa and elongation of 35.5%. Samples with lower laser energy density demonstrate the highest microhardness, reaching 365 HV. The corrosion resistance of samples with different scanning strategies is similar to pure 316L stainless steel, with the 67° interlayer rotation angle strategy showing the optimal corrosion resistance.

Investigation of negative permittivity in BaTiO3/TiN metacomposites at the radio frequency region

The intriguing and unexpected properties of metacomposites have attracted significant attention, especially in terms of tuning their negative permittivity. In this study, we fabricated percolative BaTiO3/TiN (BTN) metacomposites employing mesoporous BaTiO3 nanoparticles synthesized via a novel solvothermal method as the matrix, combined with varying concentrations of TiN as the filler. Dielectric properties investigated in the frequency range of 100 Hz to 100 kHz unveiled a transition in the permittivity, shifting from positive to negative as the TiN content increased (primarily noticeable at frequencies above 10 kHz). The initial permittivity shifting is associated with an enhanced interfacial polarization, commonly recognized as Maxwell-Wagner-Sillars effect observed below the percolation threshold. Further, Lorentz model is attributed to induce dielectric resonance in the BaTiO3 matrix triggered by the Ti4+ ions in Ti–O octahedral sites leading to negative permittivity in conjunction with increase in TiN particles above the percolation threshold. Interestingly, AC conductivity exhibited an increase with increasing frequency when TiN content was lower. However, intriguingly, this frequency-dependence in the conductivity of BTN metacomposites did not hold as TiN content increased. Moreover, the investigation of reactance revealed the inductive character derived from the conductive network, a conclusion further confirmed through equivalent circuit analysis. The findings presented in this study are poised to unlock new possibilities in the design and development of metacomposites, ultimately facilitating practical applications of epsilon-negative materials in electromagnetic devices.

Gamma radiation-induced alterations in nanocrystalline titanium nitride (TiN) particles: A structural perspective

The effect of gamma radiation on the structure of nanocrystalline TiN particles was studied. Initially, nanocrystalline TiN particles were exposed to gamma radiation at doses of 50 kGy, 200 kGy, 900 kGy and 3.5 MGy. The crystal structure of non-irradiated and irradiated samples with different doses of gamma rays was studied by X-ray diffraction method. As a result of the determination analysis of the X-ray diffraction spectra by the Rietvield method, the dependence of the lattice parameters on the radiation dose was established. The effect of gamma irradiation on the size of crystallites was determined by the Scherrer equation. The amorphization occurred in nanocrystalline TiN particles was calculated by the method of integration of diffraction peaks. It was determined that 2.5% amorphization occurred in the specified irradiation interval.

Optimization of the active element and reinforcement proportion for improving joint strength of brazed Si3N4/42CrMo

Micron-TiN particles and Ti powder were introduced into the AgCu powder filler to design a particle-reinforced composite filler. This TiN particle (TiNp) modified brazing material was adopted to reliably braze Si3N4 ceramics onto 42CrMo steel, and the ratio of active element Ti to TiNp reinforcement was optimized for joint strength improvement. The reaction layer’s thickness (TiN+Ti5Si3) adjacent to the ceramic decreased by introducing TiNp. Nevertheless, the reaction layer’s thickness (TiC) at the 42CrMo side did not vary too much. TiNp showed excellent wettability with Ag-Cu-Ti braze, and there was no obvious reaction at the interface. Cu-Ti intermetallic compounds were formed and randomly distributed in the brazing seam. When the TiNp content did not exceed 8 vol.%, the joints’ mechanical properties first sharply decreased and then remained basically unchanged when Ti increased. Raising the TiNp content to 10 vol.%, the joint strength showed the changing trends of first increasing and then dropping by increasing Ti content. The bending strength reached the maximum value of 396 MPa when 8 vol.% TiNp and 4 wt.% Ti were adopted.

In-situ synthesis of spatial heterostructure Ti composites by laser powder bed fusion to overcome the strength and plasticity trade-off

Recent research has focused on laser in-situ additive manufacturing of metal matrix composites with spatially controllable microstructures (phases). This study, inspired by the process of inserting mesh fibers into reinforced concrete, synthesizes TiN in situ using laser powder bed fusion and N2 gas. The laser-melted track, embedded with TiN particles, formed a spatially heterostructured Ti composite (SHTC) with a three-dimensional, artificially controlled architecture in a pure Ti matrix. The influences of process parameters on the mechanical properties of the spatially heterostructured Ti composite and the microstructural evolution of TiN/Ti were investigated emphatically. The results showed that the growth direction of the microstructure was changed by laser powder bed fusion additive manufacturing with alternating N2–Ar gas under suitable N2 concentration and melting track spacing. Among all spatially heterostructured Ti composites, the TiN–Ti heterolayer net-like structure achieved a high ultimate tensile strength of ∼1.0 GPa and elongation of 27 %, demonstrating a superior strength-ductility combination than intrinsic pure Ti and uniform TiN composites, as well as traditional layered structure Ti-based composites. During the tensile test, the deformation behavior was monitored in situ using digital image correlation, and the fracture mechanism was investigated. Hetero-deformation induced strengthening and toughening potentially explains the mechanism behind the strength enhancement of spatially heterostructured Ti composites. Furthermore, this work may stimulate research and development in additive manufacturing of spatial heterostructures with configurable structures, targeting synergistic regulation of strength and ductility in the integration of structure-material-function.

Enhancing mechanical properties of selective-laser-melting TiN/AISI 420 composites through Taguchi GRA and PCA multi-response optimization

The enhancement of mechanical properties in martensitic AISI 420 stainless steel is realized through the incorporation of TiN ceramic particles using the selective laser melting (SLM) method. This study introduces an innovative hybrid mixing method designed to uniformly disperse TiN within the AISI 420 matrix, ensuring the absence of agglomerations and contaminations in the feedstock for the SLM process. Employing a combined approach involving the Taguchi method, Grey Relational Analysis, and Principle Component Analysis, optimal processing parameters and TiN content are identified, encompassing a laser power of 350 W, laser speed of 370 mm/s, hatch distance of 0.07 mm, layer thickness of 0.05 mm, and one percent by weight of TiN particles. The optimized SLM sample showcases exceptional characteristics with a hardness of 743 ± 20 HV, tensile strength of 1822 ± 21 MPa, and a modulus of toughness of 99.7 ± 3.0 J/m3, surpassing existing results. Introducing TiN particles into the AISI 420 matrix with suitable SLM processing parameters induces significant microstructural alterations, reinforcing the matrix and elevating the mechanical properties. These results mark a substantial advancement in metal matrix composite materials by applying cutting-edge manufacturing techniques.