TiC Addition Research Articles

Enhanced ablation resistance and mechanical behavior of spark plasma sintered ZrB2-SiC composites with TiC addition

Enhanced ablation resistance and mechanical behavior of spark plasma sintered ZrB2-SiC composites with TiC addition

Influence of TiC and Ni addition on densification and mechanical properties of microwave sintered ZrB2 based composites

The effects of TiC (10–30 vol%) and Ni (1–2 vol%) incorporation on densification, microstructural evolution and mechanical properties of microwave sintered ZrB2 matrix-based composites were investigated in the present study. The findings reveal that TiC addition significantly improves the densification of ZrB2 based composites, while the inclusion of Ni further improves densification of ZrB2–20 vol% TiC composite by reducing porosity and restricting the grain growth of both ZrB2 and TiC phases. Additionally, the highest Vickers hardness of 22.25 ± 1.33 GPa and compressive strength of 1556.2 ± 40.17 MPa were obtained for the ZrB2–20 vol% TiC composite due to lower porosity, lower grain size and higher TiC diffusion in the ZrB2 matrix. The fracture toughness enhanced with TiC and Ni addition and the maximum fracture toughness was observed as 6.66 ± 0.47 MPa.m0.5 along with the highest critical energy release rate of 95.16 ± 11.68 J/m2 for the ZrB2–20 vol% TiC-2 vol% Ni composite owing to the activation of toughening mechanisms like crack bridging, crack deflection and open pores as crack deflectors. Nanoindentation studies revealed significant improvements in elastic modulus and stiffness with the addition of TiC. The maximum elastic modulus and stiffness were observed as 482.91 ± 36.36 GPa and 237.24 ± 20.28 μN/nm for ZrB2–20 vol% TiC composite. The study highlights the potential of incorporating metallic additives with secondary reinforcements to enhance the mechanical properties and microstructures of ZrB2 matrix, making them potential materials for high-temperature applications such as control surfaces, nose caps and leading edges of supersonic aircrafts.

Multi-scale ceramic TiC solves the strength-plasticity equilibrium problem of high entropy alloy

High entropy alloys (HEAs) with single FCC structure exhibits unique structure and properties. However, lack of strength hinds the engineering application ability seriously. Therefore, it is urgent to propose effective methods and theories to enhance the strength while maintaining favorable plasticity. Introducing reinforced phases is one crucial research approach for improving the mechanical properties of HEAs. However, the resulting reduction in ductility has been neglected. In this work, we propose a novel multi-scale TiC coupling reinforced alloy which preserves the high plasticity while increasing the strength. The results demonstrate that TiC (μm) hinders the dislocations movement and improves strength through the second phase strengthening mechanism. Apart from acting as barriers to dislocation motion, the TiC (nm) also provides more dislocation sources in the distortion area at the junction with the matrix, which increasing the number of movable dislocations and enhancing the plastic strain capacity. Compared with the Al0.4 alloy, the tensile yield strength of the Al0.4-TiC (μm + nm) alloy is increased by 145 %, the ultimate tensile strength is up to 574 MPa, while maintaining a high plastic strain by 30.1 %. The addition of multi-scale ceramic phase TiC provides a novel approach to obtain high strength and high plasticity HEAs.

Influence of TiC particle size on microstructural evolution and fracture mechanism of TiC/Al-Cu composites

Using scanning electron microscopy (SEM), electron backscatter diffraction (EBSD), and molecular dynamics simulations, this work investigated the microstructure, texture evolution, strengthening mechanisms, and fracture progression of TiC/Al-Cu composites with various particle sizes following hot extrusion and heat treatment. TiC particles significantly refine grain sizes, shifting the dominant coincidence site lattice (CSL) boundaries from Σ5 to Σ3. The addition of TiC particles alters the preferred grain orientation from (111)/ED to (001)/ED, and modifies the type and intensity of the texture. The primary strengthening mechanisms attributed to TiC include grain boundary strengthening, dislocation strengthening, Orowan strengthening, and load transfer strengthening. However, the strong tendency of smaller TiC particles to agglomerate substantially diminishes these strengthening effects; thus, under a TiC addition of 0.5 wt%, larger TiC particles exhibit better mechanical properties. Fractographic analysis and molecular dynamics simulations revealed that microcracks originate from dissociation at the interfaces between the TiC agglomerates and the Al matrix. The subsequent propagation, expansion, and interconnection of multiple crack initiation sites lead to the formation of macroscopic cracks that result in material failure.

Microstructural Stability of IN625 Reinforced by the Addition of TiC Produced by Laser Powder Bed Fusion after Prolonged Thermal Exposure.

This paper deals with the development and characterization of an Inconel 625 (IN625) reinforced with 2 wt.% of sub-micrometrical TiC particles produced by the laser powder bed fusion (LPBF) process. IN625 and IN625 2 wt.% TiC microstructural evolution was evaluated in the as-built, solution-annealed (2 h at 1150 °C), and prolonged heat-treated (2 h at 1150 °C + 100 h at 1000 °C) conditions. The IN625 and IN625 + TiC samples were successfully produced with low residual porosity (<0.15%). In the as-built conditions, both materials developed mainly columnar grains elongated to the building direction with melt pools, fine dendric structures, and small fractions of recrystallized grains. Some TiC segregations were observed in the composite, preferentially located at the melt pool boundaries. The heat treatments led to a different microstructural evolution between the base alloy and the composite. After solution annealing, the IN625 alloy was subjected to full recrystallization with a drastic reduction in hardness. Afterward, the prolonged thermal exposures for 100 h at 1000 °C provoked the formation of carbides, increasing the hardness. On the contrary, the composite retained the as-built microstructure with columnar grains in the solution-annealed and prolonged heat-treated conditions, revealing a limited formation and growth of carbides, thus resulting in a reduced hardness variation. The addition of TiC inside the IN625 enhanced the microstructural stability of the composite, preventing the recrystallization and the growth of phases occurring under prolonged thermal exposures. The current study therefore reported the effect of TiC particles on the microstructural stabilization of LPBFed IN625, with a peculiar focus on the prolonged thermal exposure at 1000 °C.

Microstructure and improved hydrogen generation performance via hydrolysis of Mg–Ca alloys with TiC and Ni addition

Mg-xCa (x = 3, 7, 11, 14, wt.%) binary hypoeutectic alloys are successfully synthesized via solidification in the present work. The microstructure, phase compositions and hydrogen generation characteristics of as-cast Mg–Ca alloys and ball milled Mg–Ca composites with TiC and Ni addition have been investigated in this work for a new hydrogen supply source application. A lamellar structure with alternately distributed Mg and Mg2Ca is formed in the eutectic regions of as-cast Mg–Ca binary alloys. It is found that as-cast Mg–Ca binary alloys show extremely sluggish hydrolysis kinetics and low hydrogen yield in both tap water and simulated seawater. Mg2Ca phase preferentially reacts with water during hydrolysis process in simulated seawater. Many cracks arise with hydrolysis reaction, meanwhile, the cracks further assist in the hydrolysis of the internal matrix via assisting water solution transfer. After ball milling with TiC and Ni of Mg–Ca binary alloys, the hydrolysis performance is substantially modified. Mg–14Ca-3wt.%TiC-5wt.%Ni composite generates 836.6 mL g−1 of hydrogen within initial 95 min. The conversion rate of Mg–14Ca-3wt.%TiC-5wt.%Ni composite in simulated seawater is as high as 99.4%, indicating a thorough hydrolysis of Mg and Mg2Ca phases with the catalysis of TiC and Ni. This work shows that microstructure refinement, catalysis, Mg(OH)2 exfoliation and water solution transfer account for the complete hydrolysis.

Achieving high strength and ductility in Inconel 718: tailoring grain structure through micron-sized carbide additives in PBF-LB/M additive manufacturing

ABSTRACT Few attempts have been made so far to develop modifiers for in situ use in Inconel 718 PBF-LB/M fabrication. Reports show an increase in tensile strength compared to unmodified counterparts. However, significant ductility reduction is observed, outweighing the mere tensile strength improvements when considering practical applications. In this study, micron-sized powder modifiers (NbC, TiC, and B4C) were added in proportions of 0.6 wt.% (NbC and TiC) and 0.2 wt.% (B4C) to Inconel 718 powder for PBF-LB/M processing. These modifiers allowed for grain structure control during heat treatment, including hot isostatic pressing. The addition of NbC resulted in a finer grain structure, while the addition of TiC preserved the as-built grain structure after heat treatment. Carbide precipitates led to uniform GND distribution and promoted uniform stress distribution. We show that the trade-off between strength and ductility in carbide-modified IN718 can be overcome by careful PBF-LB/M processing and heat treatment.

Laves phase control and tensile properties optimization of DED-arc repaired 718Plus components through the addition of TiC and Cr2C3

Directed energy deposition-arc (DED-arc) additive manufacturing technology was used to repair the damaged 718Plus components. This work shows that TiC/Cr2C3 addition to 718Plus alloy is an effective way to suppress the formation of the unfavorable Laves phase. TiC additions to 718Plus alloy can alleviate the elemental segregation, refine the dendritic structure and promote the formation of blocky TiC-NbC core-shell carbides and NbC carbides, while Cr2C3 additions enable the precipitation of rod-like NbC carbides. During the deposition process, the TiC/Cr2C3 additions were dissolved into the molten pool and decomposed into Ti, Cr, and C. The introduction of additional carbon in the melt drastically consumed the Nb available for Laves phase. The tensile tests show that TiC addition to 718Plus alloy contributed to an increased tensile strength of about 120 MPa due to the reduced amount of Laves phase and the reinforced effect of carbides. The fracture behaviour of carbides was explained in detail. The critical shear stress for blocky carbides to crack is higher than that required for rod-like ones, suggesting that TiC additions were desirable for better ductility compared with Cr2C3 additions.

Microstructure and mechanical properties of TiC reinforced NbC-Ni4VC4Mo2C cermets

Abstract The class of NbC-Ni cermets has emerged as a promising environmentally friendly alternative to WC-Co cemented carbide tools, although some inherent properties i.e. room temperature hardness and flexural strength, of NbC-Ni cermets may require further enhancements. To enhance the properties of NbC-Ni cermets, diverse methodologies were applied, including grain inhibition and the strengthening of the cermet through the use of reinforcements. This study systematically examined the impact of TiC additions, specifically at 10% and 20%, on both the microstructure and mechanical properties of NbC-12Ni-4VC-4Mo2C cermets. NbC-12Ni cermets were fabricated via vacuum liquid phase sintering (LPS) at 1400 °C and 1450 °C. Enhancements by incorporating 4% VC and 4% Mo2C, followed by TiC at 10% and 20% concentrations to the NbC-Ni-4VC4Mo2C cermet were made. XRD and SEM results confirm the formation of (Nb, X, Y) C solid solution cubic FCC carbides. Significant grain refinement was evident in the cermet samples, subjected to grain inhibition. The observed grain sizes ranged from a maximum of 6.84 μm (in NbC12Ni) to a minimum of 2.154 μm (in the sample containing 20% TiC) at 1450 °C. The incorporation of 20TiC at 1450 °C led to a remarkable 26.5% enhancement in average hardness compared to NbC-Ni cermet, and a 4.2% improvement over the 4VC4Mo2C cermet. At 1450 °C, 20TiC reinforcement led to an average fracture toughness of 9.331 MPa√m, representing a 4.56% improvement over the 4VC4Mo2C cermet. However, there was a marginal reduction in toughness compared to the NbC-Ni cermet. Moreover, the addition of TiC led to a decrease in the flexural strength of the cermets, with a maximum flexural strength of 939 N mm−2 recorded for NbC-Ni-4VC4Mo2C, representing an 11.6% increase compared to the NbC-Ni cermet.

Augmenting microstructure and tribological performance of wire arc additive manufactured PH13-8Mo stainless steel via TiC/TiB2 nano-particles incorporation

This study aimed to investigate the effect of TiC and TiB2 nano-inoculants addition on the microstructure and tribological behavior of PH13-8Mo stainless steel processed through wire arc additive manufacturing (WAAM). The incorporation of TiC/TiB2 inoculants demonstrated notable efficiency in mitigating the anisotropic wear and scratch response and enhancing wear resistance observed in the as-printed state. This improvement was ascribed to the refinement of the grain structure, disruption of the columnar structure, and increased content of the retained austenite. Notably, TiB2 inoculation exhibited superior grain refinement and achieved the highest hardness. However, the TiC-inoculated condition demonstrated the best wear resistance, attributed to its excellent combination of hardness and fracture resistance, and a higher contribution of strain-induced martensite transformation during wear testing. Additionally, the implementation of post-printing solutionizing and aging treatment was found to improve the scratch and wear resistance of the alloy, attributed to the formation of nano-sized β-NiAl precipitates. The main wear mechanism observed involved oxidation wear, adhesive wear, and three-body abrasive wear. The findings of this study highlight the significant potential of incorporating ceramic-based nano-particles for improving the wear resistance of WAAM PH13-8Mo components, particularly in demanding applications like injection molding dies where superior abrasion resistance is paramount.

EFFECT OF TiC ADDITION ON MICROSTRUCTURE AND PROPERTIES OF LASER CLADDING AlCoCrFeNi2.1 COATINGS ON H13 STEEL

[Formula: see text][Formula: see text][Formula: see text][Formula: see text]xwt.%TiC ([Formula: see text], 6, 9) coatings were prepared on H13 steel by laser cladding (LC) technology. It was characterized by a friction and wear test machine, optical microscope (OM), X-ray diffractometer (XRD), hardness tester, etc. The effects of different TiC contents on the microstructure and properties of [Formula: see text] coatings were analyzed. The results show that the coating microstructure without TiC addition is dominated by coarse columnar crystals and dendrites. After the addition of TiC, the coated massive crystals and equiaxed crystals become finer. XRD analysis reveals that the phase structure of the coating has FCC, B2 solid solution phase and TiC-reinforced phase. TiC phase can significantly improve the hardness of the coating. The microstructure reveals that fine TiC particles are widely distributed among the dendrites of the FCC matrix. The hardness and friction wear experiments revealed that the average hardness of the coatings with TiC has increased significantly compared to that of the substrate. The hardness of the [Formula: see text] with 9%TiC coating increased by 184.6% compared to that of the substrate. The friction coefficient was the smallest at 0.748. The lowest self-corrosion current was [Formula: see text][Formula: see text][Formula: see text]. The [Formula: see text] with 9%TiC coating had the best corrosion resistance.

Microstructure and mechanical property improvement of concurrent wire-powder feeding laser melting deposition Ti-6Al-4V via TiC addition

Wire-feed laser metal deposition (LMD-W) offers a high deposition rate and low cost, making it an effective solution for reducing costs and enhancing efficiency in manufacturing large-scale titanium aerospace components. Currently, the material used for LMD-W is typically a single alloy wire, which limits the flexibility and functionality of manufacturing composite materials. This work employed a novel concurrent wire-powder feeding laser metal deposition (LMD-WP) process to manufacture TiC/Ti-6Al-4V composite. In the LMD-WP method, Ti-6Al-4V wire was fed laterally, while TiC particles were delivered coaxially. Only 1.0 wt% TiC particles were added to prevent excessive TiC, which could cause stress concentration and increase crack sensitivity. The microstructure and mechanical properties of Ti-6Al-4V alloy and TiC/Ti-6Al-4V composite were investigated. The results indicate that with coaxial TiC particle addition, the α-Ti in TiC/Ti-6Al-4V is noticeably refined. Additionally, in situ TiC acts as heterogeneous nucleation sites, restricting α-Ti growth and reducing its aspect ratio. Furthermore, TiC particles weakened the α-Ti texture in the (0001) and (11–20) directions. Moreover, adding TiC particles significantly enhanced tensile strength, with the yield strength reaching 950 MPa and the ultimate tensile strength reaching 1048 MPa. Compared to Ti-6Al-4V alloy fabricated by LMD-W, this represents an increase of 11.25% and 10.72%, respectively. The improvement in tensile properties is principally ascribed to grain boundary strengthening, Orowan strengthening and dislocation density strengthening. This work introduces an innovative approach and abundant data for the additive manufacturing of TiC/Ti-6Al-4V composite with high efficiency and low cost.

Microstructure and tribological properties of laser cladded TiC reinforced WC-10Co4Cr coatings at 500 °C

WC-10Co4Cr-xTiC coatings were fabricated on H13 steel by laser cladding to improve their wear resistance. The effects of TiC mass fraction on the friction-wear properties at 500 °C were investigated using a high-temperature wear tester, and the wear mechanism was discussed in detail. The results show that the WC-10Co4Cr-xTiC coatings are composed of WC, W2C, Co3W3C, Cr7C3, and TiC phases, and the porosity is reduced by the addition of TiC. The average coefficients of friction of WC-10Co4Cr-xTiC coatings are increased with the TiC mass fraction; while the wear rates are opposite, showing that the addition of TiC plays a key role in wear resistance. Moreover, the wear mechanism of WC-10Co4Cr-xTiC coatings is primary abrasive wear, slight adhesive wear, and oxidative wear.

Microstructural characteristics and wear-resistant mechanisms of WC-TiC-co coatings with varying TiC contents

In this work, the microstructural characteristics and tribological properties of HVOF-sprayed WC-TiC-Co coatings with varying amounts of TiC addition were studied, along with a comparison with those of the traditional WC-Co coating. The incorporated TiC exhibited a diverse presence in the coatings, including (Ti,W)C solid solution particles and interfacial layers, residual TiC particles, as well as Ti-monolayer that induced planar defects within WC grains. The high stability of (Ti,W)C layers at the WC/Co interfaces effectively suppressed the formation of W2C in the WC-TiC-Co coatings. Notably, the coating with 10 wt% TiC demonstrated superior wear resistance owing to the hardening effects of (Ti,W)C particles and interfacial layers. This effectively mitigated the wear mechanisms such as plastic deformation, extrusion, and micro-cutting of the Co binder, which would otherwise lead to the pull-out of WC particles and accelerate the wear process. These findings provide valuable insights into the microstructure design and performance optimization of WC-based coatings.

Microstructure and tribological behaviors of laser cladded CuAlMnTi–xTiC composite coatings at elevated temperature

CuAlMnTi-xTiC composite coatings were prepared on Ti6Al4V alloy by laser cladding to enhance its tribological properties. The effects of TiC mass fraction on the friction–wear properties of CuAlMnTi–xTiC composite coatings at high–temperature were investigated using an ball–on–disc tester. The results show that the grains of CuAlMnTi–xTiC composite coatings are refined by the addition of TiC, and the metallurgical bonding is formed between the coating and the substrate. The hardness of CuAlMnTi–15%TiC composite coating is higher 1.98 times than that of CuAlMnTi coating, in which the TiC as wear–resistant framework prevents micro–cutting to enhance wear resistance. The average coefficients of friction of CuAlMnTi–0%TiC, –5%TiC, –10%TiC and –15% TiC composite coatings in the stable wear period are 0.465, 0.491, 0.514, and 0.587, respectively, and the corresponding wear rates are 116.8, 111.3, 107.8, and 95.4 μm3•N–1•mm–1, respectively, showing that the wear rate is decreased with the increase of TiC mass fraction. The wear mechanism is transferred from adhesive wear to abrasive wear and slight oxidation wear by the addition of TiC, which is attributed to the improvement of hardness by the refined grain strengthening effect of TiC.

The strengthening mechanism of mechanical and tribological properties of TiC-reinforced 316L matrix composites fabricated by selective laser melting

Selective laser melting (SLM) has been proved to be a promising additive manufacturing technique to fabricate high-performance metal matrix composites (MMCs) with unique microstructures. In this study, TiC-reinforced 316 L MMCs were successfully prepared by SLM. The effects of TiC addition on the microstructure evolution, mechanical properties and tribological behavior were systematically investigated to study the strengthening mechanism. The TiC/316 L MMCs fabricated by SLM exhibited a high relative density of over 99.6% and were close to full density. The TiC particles are effectively bonded with the 316 L matrix, serving as a means of dispersion strengthening. In addition, the grains were significantly refined, and the dislocation density was greatly enhanced with the addition of TiC particles, which reinforce the strength of the material. Tensile tests show that the tensile strength of TiC/316 L MMCs increased by 49.9% from 707 to 1060 MPa and yield strength increased by 44.2% from 543 to 783 MPa with 4 wt% TiC. Besides, the tribological behavior of TiC/316 L MMCs was much superior to the pure 316 L. The findings provide a new perspective on ceramic particles reinforced stainless steel MMCs with tailored microstructure and excellence performance.

Effects of WC/TiC addition on the thermodynamic behavior of TiB2-based cermet during sintering process

The heat absorption, weight change and exhaust behavior of TiB2-based cermet powder mixtures with additions of WC, TiC and WC-TiC were analyzed by a simultaneous thermal analyzer coupled with a mass spectrometer (TG/DSC-QMS). Thermodilatometry was used to investigate the densification behavior due to sintering process of cermets. During the sintering process, the order of degassing is: water vapor, CO2 released by the reduction of adsorbed oxygen in the raw material powder, CO and CO2 released by the reduction of surface oxides of Co and Ni powder, WC powder, TiB2 and TiC powder. The addition of WC, TiC and WC-TiC accelerated the reduction of oxides on the surface of Co and Ni powders, and decreased the temperature point of liquid phase formation in TiB2-based cermet. WC and TiC dissolved in liquid CoNi binder and then precipitated on the undissolved TiB2 particles to form a typical core-rim structure during the sintering. This study is expected to lay a solid foundation for the development of high-performance TiB2-based cermets based on TiB2-CoNi, TiB2-WC-CoNi, TiB2-TiC-CoNi and TiB2-WC-TiC-CoNi cermets in the future.

Effects of TiC addition on the interface stability, microstructure, and mechanical properties of IN718 fabricated by laser direct metal deposition: A combined experimental, DFT and MD study

In this study, we reveal the impact of the addition of TiC in the IN718 superalloys at both atomic and micron scales through density functional theory (DFT), molecular dynamics (MD), and experimental analysis. From the micro scales, the addition of TiC can effectively mitigate the segregation behavior of Nb and Mo atoms, promote heterogeneous nucleation, reduce grain size, and thus improve mechanical properties. From the atomic scales, the effect of alloying elements (Fe, Cr, Mo, Nb, Co) on the stability of the TiC/γ-Ni interface was investigated through first principles. Co-doping interface was more stable than other interfaces by MD calculations, followed by Cr and Fe-doping models. The heat of segregation results inferred that TiC can effectively mitigate the segregation behavior of Nb and Mo atoms in the TiC/γ-Ni interface, it is mutually verified with the experimental results. Furthermore, the interface energy values theoretically illustrated that TiC particles could promote the heterogeneous nucleation of γ-Ni, this behavior of TiC particles was verified by experiment results. This investigation results provide reference information in the study of ceramic particle reinforced alloys at atomic and micron scales.

Role of TiC and WC Addition on the Mechanism and Kinetics of Isothermal Oxidation and High-Temperature Stability of ZrB2–SiC Composites

Role of TiC and WC Addition on the Mechanism and Kinetics of Isothermal Oxidation and High-Temperature Stability of ZrB2–SiC Composites

Microstructure and properties of Ni-based VC and TiVC2 composite coatings fabricated in situ by laser direct deposition

Ni-based VC and TiVC2 composite coatings were prepared on the surface of worn brake discs by laser direct deposition, and the influence mechanism of trace TiC addition on the microstructure and performance of the coating was investigated. The microstructure of the coatings was analyzed by XRD, SEM, EDS, and TEM, which revealed the evolution mechanism of the microstructure during the laser deposition process. The friction wear performance was tested on friction wear equipment. The results showed that VC0.88 was formed by the in-situ reaction of C and V under the action of the laser, which presents dendritic morphology. After the addition of TiC particles, TiVC2 was further synthesized along the TiC particles in addition to dispersed VC0.88 in the coating. It can be seen that the addition of trace TiC particles inhibited the formation of VC0.88 dendrites and enhanced the plastic toughness of the coating. HRTEM calibration proved the existence of TiVC2 and Ni, and there was no obvious orientation relationship between the interface. The friction coefficients of Ni-based VC and Ni-based TiVC2 coatings with Al2O3 balls were 0.59 and 0.51 at room temperature, respectively. After 1.5 h of high-temperature wear at 300 °C and 600 °C, the distribution of wear marks shows a groove and high-temperature fatigue appearance. The TiC-doped coating has better wear properties than the base material and the original coating is expected to meet the requirements for brake discs.