Effect Of TiB2 Research Articles

Effect of TiB2 on the Microstructure and Mechanical Properties of TiB2/Al-5Cu Matrix Composites

Effect of TiB2 on the Microstructure and Mechanical Properties of TiB2/Al-5Cu Matrix Composites

Improving wear and corrosion resistance of HVAF sprayed 316L stainless steel coating by adding TiB2 ceramic particles and CeO2

316L stainless steel is used in a wide variety of corrosion-prone locations. However, its low hardness and poor tribological properties limit its application under heavy wear conditions. In this study, 316L Fe-based composite coatings co-doped with TB2 hard phases and rare-earth CeO2 exhibited excellent wear and corrosion resistance. Firstly, 316L-TiB2 cermet powder and (316L-TiB2)/CeO2 composite powder with high sphericity and density were prepared by high energy ball milling (HEBM), spraying drying granulation (SD), plasma spheroidization (PS) process. Then, 316L coatings, 316L-TiB2 and (316L-TiB2)/CeO2 cermet coatings were deposited by high velocity air fuel (HVAF) spraying. Finally, the effects of TiB2 and CeO2 additions on the microstructure, wear and corrosion behavior of the coatings were investigated. The results showed that TiB2 hard particles and CeO2 were uniformly distributed in the HVAF sprayed 316L-TiB2 and (316L-TiB2)/CeO2 coatings. The wear resistance of the coating prepared by 316L Fe-based composite powder with TiB2 and CeO2 is significantly improved. The hardness of the (316L-TiB2)/CeO2 composite coating was increased from 269 Hv0.3 to 826 Hv0.3 for the pure 316L coating, while the volumetric wear rate was only 3.6 % of that of the pure 316L coating (110 × 10−5 down to 4 × 10−5 mm3/N). Electrochemical tests show that the corrosion resistance of the coating decreases with the addition of TiB2 alone, but it can be improved by doping CeO2. The 316L Fe-based coating prepared by adding TiB2 and CeO2 can significantly improve the wear resistance of the coating, while the corrosion resistance decreases only slightly.

Effect of TiB2 on the microstructure and mechanical properties of TiAl alloy produced by laser direct energy deposition

A Ti-48Al-2Cr-2Nb alloy was prepared by laser directed energy deposition (DED). The microstructure of the DED-produced Ti-48Al-2Cr-2Nb alloy exhibited a coarse columnar structure along the building direction. Through a combination of experiment and numerical simulation, the temperature gradient and solidification rate of the single-track sample were calculated theoretically. The columnar to equiaxed transition (CET) behavior of molten pool solidification was quantitatively analyzed, and the microstructure transition diagram was established. The effect of TiB2 on the microstructure and mechanical properties of the TiAl alloy was investigated. The columnar changed to equiaxed grains in the vertical cross section by adding nanometer-sized TiB2 particles and the microstructure was significantly refined. The grain size was reduced from 48.5 μm to 4.9 μm. Some equiaxed γ grains were distributed around the banded TiB2. The compressive properties were improved from 628.4 MPa to 698.8 MPa by adding nanometer-sized TiB2 particles. Finally, the solidification behavior and the microstructure refinement mechanism caused by the addition of TiB2 particles were discussed.

Effect of TiB2 on the second Bi-rich phase in immiscible Al-Bi alloy

Immiscible alloys are easy to form segregation due to their liquid phase separation characteristics. Refractory solid particles have been proved can inhibit the segregation of the second phase in this type of alloy during solidification process by either promoting nucleation or preventing the coagulation of the second phase. However, it is not clear that whether the solid particle could provide a steric hindrance effect after serving as nucleation particles. In the present work, the refining mechanism of TiB2 solid particles on the second Bi-rich phase in Al92Bi8 alloy was disclosed in both the terms of heterogeneous nucleation and steric hindrance effect. The results showed that TiB2 particles have remarkable refining effect on the second Bi-rich phase in Al92Bi8 alloy. TiB2 particles first act as nucleation particles to promote nucleation of the liquid Bi-rich phase, then migrate to and self-assemble on the interface between the liquid Bi-rich phase and the Al matrix to reduce the system interfacial energy, furtherly providing steric hindrance effect to prevent the collision and coagulation of the liquid Bi-rich phase.

Microstructure and performance optimization of Al2O3/TiC/TiB2/h-BN@Al2O3 self-lubricating ceramic tool materials

Based on the classical Monte Carlo (MC) model and grain growth theory, the model of h-BN@Al2O3 coated solid lubricant was designed and introduced into the simulation system. The Al2O3/TiB2/h-BN@Al2O3 self-lubricating composite ceramic tool model was designed, and the microstructure evolution of tool materials during hot pressing sintering was simulated. The effects of TiB2 and h-BN@Al2O3 content on the microstructure of ceramic materials were studied, and finally the optimized composition parameters were obtained. The effects of sintering temperature and sintering pressure on the microstructure of tool materials were studied, and reasonable sintering parameters were obtained. The experimental results show that under the sintering temperature of 1650℃ and sintering pressure of 32Mpa, the ceramic material with 10%volTiB2 and 5%volh-BN@Al2O3 has the best mechanical properties, that is, the bending strength is 610MPa, the hardness is 17.9GPa, and the fracture toughness is 5.17 MPa·m1/2. SEM analysis shows that the grain growth of the material is uniform, the solid lubricant is well combined with the matrix, and the material has a good microstructure. Comparing the simulation results with the previous experimental results, it is found that the results are in good agreement, which indicates that the designed MC model reliably reflects the physical process of material grain growth, and has certain guiding significance for further research on the mechanism of grain growth.

Effect of TiB2 and BN Coatings on the Thermal and Stress-Strain State of the Surface Layer of Si3N4–TiC Ceramics Under the Action of Heat Flow

Effect of TiB2 and BN Coatings on the Thermal and Stress-Strain State of the Surface Layer of Si3N4–TiC Ceramics Under the Action of Heat Flow

Effect of TiB2 and BN coatings on stress state of Si3N4‒TiC ceramics surface layer under force loading

Изучены особенности влияния покрытий TiB2 и BN на деформацию и напряженное состояние поверхностного слоя Si3N4‒TiC-керамики под действием силового нагружения. Установлено, что покрытие BN более благоприятно влияет на напряженно‒деформированное состояние структурных элементов керамики, чем покрытие TiB2. Влияние покрытий TiB2 и BN на напряженное состояние границы между керамикой и покрытием не столь однозначно: в пользу каждого покрытия свидетельствуют по три коэффициента.

Effect of TiB2 and BN Coatings on Stress State of Si3N4–TiC Ceramics Surface Layer Under Force Loading

Effect of TiB2 and BN Coatings on Stress State of Si3N4–TiC Ceramics Surface Layer Under Force Loading

Effect of TiB2 on mechanical and corrosion properties of Al 7075/TiB2/Gr composite prepared by stir casting

The current study examined the microstructural, mechanical, and corrosion properties of a metal matrix composite based on an aluminium alloy (AA7075). Three types of stir-cast metal matrix composites were created by reinforcing varying amounts of titanium diboride (2, 4, and 6 wt%) in the base alloy aluminium AA7075 while keeping the graphite content constant at 5 wt%. The optical microstructural features show that the alloying additions of graphite and titanium diborides have been homogeneously mixed in the matrix phase with no agglomeration. The tendency of particle segregation along the inter-dendritic region increases as titanium diboride content increases. The hardness and tensile properties of composite materials increase as the weight percentage of titanium diboride increases. Although the increase in hardness is small,the increase in tensile properties is significant and significantly greater than the base aluminium alloy AA7075. The corrosion rate of three metal matrix composite variants was determined using the weight loss method in three different corrosive solutions: aqueous (water), acidic (HCl - Concentration 0.3 N), and basic (NaOH - Concentration 0.3 N). The overall corrosion rate of all composites is significantly lower in aqueous solutions compared to acidic and basic solutions. The composite containing 4% titanium diboride has the highest corrosion rate in both acidic and basic solutions.

Investigation of the hot deformation behavior and microstructure evolution of TiB2 +TiAl3/2024Al composite

In this study, the hybrid aluminum matrix composite reinforced with TiB2 and TiAl3 particles was fabricated by in situ synthesis. Hot compression tests were performed at a deformation temperature range of 300 − 450 ℃ and strain rates of 0.001 − 1 s−1 on a Gleeble-3500 system to investigate the hot deformation behavior of the fabricated composite. The experimental results show that the flow stress was sensitively dependent on the strain rate and temperature, and the peak stress level increased with the decrease of deformation temperature or the increase of strain rates. A sine-hyperbolic constitutive equation with the hot deformation activation energy of 244.844 kJ/mol was established to describe the flow stress of the composite. Further, the effects of TiB2 and TiAl3 particles on the flow stress levels of the composite under different hot deformation conditions were described by the developed strengthening model. It found that the predicting values of yield strength calculated by the established model agreed well with the experimental data, and the nano-sized TiB2 had a greater contribution to the stress level of the composite compared to the micro-sized TiAl3. Based on the microstructure characterization, dynamic recovery (DRV) was found to be the main flow softening mechanism during hot deformation and the evolution of dynamic recrystallization (DRX) was insufficient. Micro-sized TiAl3 particles and TiB2 particle clusters can promote DRX nucleation and growth of newly formed grains, meanwhile, separated nano-sized TiB2 particles had a pinning effect on the dislocation migration leading to substructure formation, which was in favor of the development of DRV.

Microstructure and mechanical properties of a novel (TiB2+TiC)/AlSi10Mg composite prepared by selective laser melting

The (TiB2+TiC)/AlSi10Mg composite powders with 1.5 wt% nano-TiB2 particles and 1.5 wt% nano-TiC particles were prepared by ball milling. Aluminum matrix composites (AMCs) reinforced by TiB2 and TiC were fabricated via SLM with optimal processing parameters. The (TiB2+TiC)/AlSi10Mg composites showed a very high ultimate tensile strength ∼552.4 MP and excellent ductility ∼12%, which is 40.3% and 166.7% higher than that of unreinforced AlSi10Mg, respectively. The effects of TiB2 and TiC nanoparticles on the SLM processability, microstructures, grain size, and crystallographic texture of (TiB2+TiC)/AlSi10Mg composite were systematically investigated to uncover its underlying strengthening mechanisms. The results showed that the addition of 1.5 wt% nano-TiB2 and nano-TiC particles can obtain fine-equiaxed grains, facilitate microstructural homogeneity, and consequently improved mechanical properties of AlSi10Mg alloy. With the addition of TiB2 and TiC nanoparticles, the coarse columnar grains are completely transformed into equiaxed grains and the average grain size decreases from 12.1 μm to 1.5 μm.

Effect of TiB2 on the self-crack-healing ability of SiC-Si coating at 1300 °C

TiB 2 -SiC-Si coating was prepared on the surface of C/C composites by slurry immersion pyrolysis combined with gas-phase silicon infiltration method. The influence of the addition of TiB 2 on the oxidation resistance of Si-SiC coating was studied. TiB 2 significantly increases the oxidation protection time of the SiC-Si coating at 1300 °C. The TiB 2 modified Si-SiC coating displayed a weight increase (0.03%) after oxidation at 1300 °C for 300 h, while the unmodified coating had a weight loss of 0.84% after oxidation at 1300 °C for 100 h. It is found through experiments that doping TiB 2 produces more molten glass phases when the ceramic coating is oxidized at 1300 °C, which effectively heals cracks and plays a good protective performance. • A TiB 2 -SiC-Si coating with self-crack-healing ability was fabricated. • Oxidation and thermal shock resistance of the coating were investigated. • The mass increase of the samples was 0.03% after oxidation at 1300 °C for 300 h. • The weight loss of the TiB 2 -SiC-Si coating is 0.82% after 30 thermal cycles. • TiB 2 can promote the healing of cracks in the coating.

Effects of nano-sized TiB2 particles and Al3Zr dispersoids on microstructure and mechanical properties of Al–Zn–Mg–Cu based materials

The effects of TiB2 and Zr on the microstructure, aging response and mechanical properties of hot-extruded Al–Zn–Mg–Cu based materials were investigated and compared by multi-scale microstructure characterization techniques. The results showed that proper addition of TiB2 particles could refine grain size during solidification, promote dynamic recrystallization during extrusion, and inhibit grain growth during solution treatment. Meanwhile, Zr addition had minor influence on the grain refinement during solidification, but could effectively suppress recrystallization and grain growth compared with the Zr-free alloy. Furthermore, the TiB2 addition could simultaneously enhance the aging kinetics and peak-aged hardness of the materials. Comparatively, Zr addition could also improve the peak-aged hardness with minor effect on the aging kinetics of the materials. Finally, the quench sensitivity, elastic modulus and tensile properties of the materials were compared and studied. Specifically, the relationship between the microstructure and mechanical properties, and the strengthening mechanisms were discussed in detail.

Effect of TiB2 and Al3Ti on the microstructure, mechanical properties and fracture behaviour of near eutectic Al-12.6Si alloy

Effect of TiB2 and Al3Ti on the microstructure, mechanical properties and fracture behaviour of near eutectic Al-12.6Si alloy

Effect of TiB2 addition on the microstructural, electrical, and mechanical behavior of Cu–TiB2 composites processed via spark plasma sintering

Abstract In this investigation, copper–TiB2 metal matrix composites were fabricated by spark plasma sintering. The effect of TiB2 (2.5, 5, 7.5, and 10 wt.%) additions on the microstructural, electrical, and mechanical properties of the composites was investigated. There was a remarkable reduction in processing time and temperature by this process as compared to conventional sintering. Scanning electron microscopy with energy dispersive X-ray spectroscopy elemental maps revealed a homogeneous distribution of TiB2 in the copper matrix. The hardness of the composites exhibited no consistent trend with the addition of TiB2. An improvement in tensile strength was observed at the expense of ductility. Electrical conductivity showed a decreasing trend. Morphology of the fracture surfaces was analyzed to predict the nature of failure under tensile load.

Microstructure and properties of hot pressed TiB2 and SiC reinforced B4C–based composites

B4C ceramics were strengthened by introducing the hard second–phase particles TiB2 and SiC, and the effects of TiB2 and SiC contents on the microstructure and properties of the composites were investigated. B4C–TiB2 binary composites with TiB2 contents of 10, 20, 30, and 40 vol% were prepared by hot pressing. The microstructure, mechanical properties, and electrical properties of the composites with different TiB2 contents were investigated and compared. The results showed that the B4C–30 vol%TiB2 composite obtained the best comprehensive properties, with a relative density, hardness, bending strength, fracture toughness, and conductivity of 97.9 %, 29.5 GPa, 590 MPa, 6.41 MPa m1/2, and 7.6 × 104 S/m. The compressive stress generated on B4C, crack deflection induced by TiB2, and conductive network formed by TiB2 are of great significance in the context of the properties of the B4C–TiB2 composites. In addition, B4C–TiB2–SiC ternary composites with SiC contents of 0, 10, and 20 vol% were also fabricated by hot pressing. The effect of SiC content on the microstructure and mechanical properties, and the effect of SiC on the antioxidant properties of the composites were investigated. The results showed that the B4C–30 vol%TiB2–10 vol%SiC composite had the best comprehensive properties, with a relative density, hardness, flexural strength, fracture toughness, and residual flexural strength (1600 ℃) of 98.8 %, 29.5 GPa, 621 MPa, 6.80 MPa m1/2, and 465 MPa. The inhibition of the growth of SiC to other grains, removal of oxide impurities, and repair of damage by SiC oxidation products play an important role in the performance of the B4C–TiB2–SiC composites.

Effect of TiB2 on the Phase Composition, Microstructure, and Tribological Properties of AlCoCrFeNi/TiB2 Composites

Effect of TiB2 on the Phase Composition, Microstructure, and Tribological Properties of AlCoCrFeNi/TiB2 Composites

The Effect of TiB2 on Electrochemical Performance of Udimet 700 Alloy in 1 M Hydrochloric Acid Solution and Its Corrosion Inhibition Using Some Organic Derivatives

The effect of adding 5 and 10% of TiB2 on the corrosion of Udimet 700 (U700) in 1 M HCl including altered concentrations of organic compounds was considered at 25°C by electrochemical methods: potentiodynamic polarization (PP), electrochemical impedance spectroscopy (EIS) and electrochemical frequency modulation (EFM) methods. Microstructure characterization of these alloys was studied by X-ray diffractometer. Tafel plots confirmed that the appearance of examined components had a slight effect on the polarization curves. The Nyquist plots demonstrated that the charge transfer resistance (Rct) increase for the examined compounds was much higher with compound II compared to compound I. Bode plot revealed that, the total impedance raised with increasing inhibitor concentration and the constant increment in the phase angle shift was clearly related to increasing of the inhibitor concentration adsorbed on alloy species. EFM results showed an agreement with PP and EIS.

In-situ X-ray radiography of primary Fe-rich intermetallic compound formation

The formation of primary Fe-rich intermetallic compound crystals and the effect of TiB2 and TiC inoculation during solidification of a hypereutectic Al-Fe alloy has been investigated. Both horizontal, near isothermal conditions and vertical, directional thermal gradient conditions were studied using laboratory and synchrotron X-ray radiography. TiB2 and TiC inoculation enhanced formation of Fe-rich intermetallics under all experimental conditions. Near isothermal solidification resulted in the highest intermetallic number density and average formation rate, whilst increasing the thermal gradient reduced both. A model for intermetallic crystal formation is proposed to explain the effect of thermal gradient and cooling rate on the intermetallic number density and average formation rate.

Electrospark Deposition of Fenicrbsic–Meb2 Coatings on Steel

The effect of TiB2 and CrB2 additions to the commercial self-fluxing FeNiCrBSiC eutectic alloy on the structurization of electrospark coatings was examined. The mass transfer kinetics in the electrospark deposition of FTB20 (FeNiCrBSiC + 20% TiB2) and FCB20 (FeNiCrBSiC + 20% CrB2) composite materials and commercial self-fluxing FeNiCrBSiC alloy coatings onto steel 45 using an Alier-52 unit was studied. When the energy parameters of electrospark deposition increased, the mass transfer coefficient became higher and the electrospark coatings thicker and rougher. To reinforce the steel surfaces of machine parts operating in sliding friction conditions, application of the FTB20 and FCB20 coatings using an Alier-52 unit (2 and 4 modes at 1– 2 min/cm2) is recommended. The electrospark deposition of FTB20 and FCB20 electrodes leads to a heterophase structure on steel, consisting of an iron–nickel matrix and fine inclusions of chromium and/or titanium borides. The boride sizes in the developed coatings reach about 1 μm, which is one order of magnitude smaller than in the electrode materials (20 μm). In the deposition of the FCB20 electrode on steel, numerous cracks generate in the modified layer and deteriorate the service properties. The addition of TiB2 and CrB2 to the self-fluxing alloy increases the wear resistance of the electrospark coatings by four to five times as compared to the coatings produced from the commercial self-fluxing FeNiCrBSiB alloy (PG-Zh14 grade).