TiB2 Research Articles

Influence of the composition of a boron-containing active medium in the form of a coating on the structure and properties of a diffusion layer on titanium parts

A comparative study of VT-1.0 titanium boriding, carboboronizing and borosiliconizing methods was carried out in order to increase wear resistance in aggressive environments at elevated temperatures. The microstructure of diffusion coatings was investigated, their thickness and microhardness were determined. Diffusion saturation of 10×10×25 mm VT-1.0 titanium samples was carried out from saturating coatings based on boron carbide. Process temperature of 950 °C, and saturation time of 1.5 h were used as saturation conditions. At the end of high-temperature exposure, samples were removed from the furnace and cooled in air to room temperature, cleaned from saturating coatings with wooden spatulas, and boiled in the soap and soda solution for 1 h. A continuous diffusion layer 80–100 μm thick forms on the titanium surface. The borosiliconized diffusion layer obtained by titanium saturation from the mixture of 45%B 4 C–5%Na 2 B 4 O 7 –22%Si–5%NaF–3%NaCl– 20%CrB 2 has a higher microhardness: 1520 HV 0.1 versus 1280 HV 0.1 for carboboride one and 1120 HV 0.1 for boride one. In this case, boride and carboboride coatings, obtained, respectively, by saturation from 45%B 4 C–5%Na 2 B 4 O 7 –5%NaF–25%Al 2 O 3 –20%CrB 2 and 70%B 4 C– 5%Na 2 B 4 O 7 –5%NaF–20%CrB 2 coatings have a pronounced zonal structure. The upper zone of these coatings having high microhardness also features high brittleness indicators, which makes it impossible to accurately measure microhardness distribution due to chipping and cracking at microhardness measurement points. The qualitative composition of coatings on titanium was studied by X-ray diffraction using the DRON-6 X-ray diffractometer in filtered CuK α radiation (λ = 1.5418 Å) in the angle range of 2θ = 20÷80°. The diffusion coating exhibits reflections of titanium carbide, chromium and titanium borides, and a certain amount of the Cr 2 Ti intermetallic compound. Boride phases of chromium and titanium refer to high boron phases with high specific boron content: TiB, CrB, Ti 2 B 5 , Ti 3 B 4 и Cr 2 B 3 .

Influence of titanium diboride and graphite on microstructure characteristics and mechanical behaviors of aluminium hybrid nanocomposites

The present work investigates the influence of graphite (Gr) on microstructure and mechanical behaviour of Al7075/TiB2/2wt%Gr hybrid nanocomposite. Aluminium matrix hybrid nanocomposites (AMNCs) were fabricated using electromagnetic stir casting technique. The hybrid nanocomposites were characterized by optical Microstructure (OM), X-ray Diffraction (XRD), Energy Dispersive X-ray Spectrum (EDAS) and Scanning Electron Microscope (SEM). The Al7075/TiB2/Gr hybrid nanocomposties was prepared with 2 wt% Gr nanoparticles addition and 2.5, 5, 7.5, 10 and 12.5 wt% of TiB2 nanoparticles. Results revealed that with the addition of reinforcement hardness of nanocomposties were increased by 145.42BHN to 173.48BHN. Significant improvements in tensile strength, compression strength and flexural strength of AMNCs were attained upto10 wt% TiB2 addition, further decrease in strength at 12.5 wt% TiB2 addition in Al7075 and Al7075 alloy. Considerable enhancement in mechanical properties shows homogenous distribution and agglomerated along the grain boundaries decreases the mechanical properties of the reinforced nanoparticles in the matrix.

The electrophoretic deposition of TiB2 nanoparticles produced by pulsed laser ablation: Case study on microstructural features and micromorphology properties.

In the last decade, laser Ablation technique (Nd:YAG) has been considered as a perfect method for producing nanostructures with high purity. In the present study, Titanium diboride nanoparticles (TiB2 NPs) have been deposited on Aluminum (Al) and their micromorphology and microstructural properties have been investigated. The synthesis of TiB2 NPs has been carried out by the Laser Ablation technique (Nd:YAG) which has not been reported so far. Moreover, the effects of laser energy on improving the synthesis of TiB2 NPs have been examined. In this regard, five samples of TiB2 NPs were prepared by Laser Ablation method in different values of laser fluency in the range of 0.4-1.2J/cm2 . The structural properties of prepared nanoparticles were detected by grazing incidence X-ray diffraction, transmission electron microscopy, and energy dispersive X-ray spectroscopy. The morphology of samples was also investigated by field effect scanning electron microscopy. The results demonstrate the formation of spherical nanoparticles in all samples. Based on the results of the GIXRD patterns, pulsed laser energy is an effective parameter for the size of ablated nanoparticles. As can be seen, increasing the energy of laser beam decreases the average size of nanoparticles from 79.41 to 4nm. As the next step, the as-prepared nanoparticles were deposited on Aluminum substrate with electrophoretic deposition technique at constant applied voltage (30 Volt) and constant deposition time (30 min). The X-ray diffraction pattern of TiB2 NPs deposited onto Al substrate confirmed the formation of the TiB2 thin films on all Al substrates. Also, the roughness and average particle size of deposited films were measured by atomic force microscopy images and MountainsMap® Premium software. Increasing the fluency of laser beam made the surface more irregular and the maximum value of fractal dimension and hence, the most irregular topography has been observed in the sample produced by maximum laser fluency. RESEARCH HIGHLIGHTS: Titanium diboride nanoparticles have been synthesized by the laser ablation technique. The effects of laser energy on improving the synthesis of TiB2 NPs have been investigated. The micromorphology of samples have been investigated by analyzing AFM and SEM images.

Investigation of Wear Behaviour and Mechanical Properties of Titanium Diboride Reinforced AMMC Composites

The aluminium metal matrix composites (AMMCs) are preferred in automotive and aerospace industries for higher strength, weight ratio, good corrosion resistance, and also better tribological properties. This study proposed that the AA7075 alloy methodology was enhanced by stir casting with titanium diboride (TiB2) particles at different percentages (5, 10, and 15 wt. %). The preheated titanium diboride powder is spread to the molten state AA7075 at 870°C to provide good weight resistance and delivery. The prepared composites are evaluated by wear analysis, tensile properties, hardness range, and microstructural behavior studies. Pin-on-disk and Rockwell hardness tester were used to analyze the wear behaviour and hardness level. The tensile strength and hardness have defined the strength of the proposed composite while the addition of TiB2 particles improves the hardness and tensile stress. The findings showed that adding TiB2 particles in the Al7075 matrix strengthened all properties compared to the Al7075 matrix. The scanning electron microscope and EDS were used to analyze the eroded surface and chemical composition of composites.

Research Status of Titanium Diboride High Temperature Ceramics

Titanium diboride has a series of excellent physical and chemical properties, high melting point and hardness, good thermal stability and oxidation resistance. As an excellent hard phase, titanium diboride is used in new materials such as composite materials and cermet. It has a wide prospect in the application of high-temperature ceramics. In this paper, the research status, performance structure, preparation method and application of titanium boride high-temperature ceramics are analyzed and summarized from the overall point of view, and the main problems faced by titanium boride at present are also discussed. Finally, the future research direction of titanium boride high temperature ceramics is discussed.

Spark plasma sintering assisted rapid growth of titanium boride layers on titanium: Microstructures and growth kinetics

To increase the surface hardness of titanium (Ti), the boride layers composed of TiB 2 and TiB, were prepared on the CP-Ti substrate by spark plasma sintering (SPS) technique with micro-TiB 2 powders as boride source. Effects of sintering temperature and holding time on the microstructure, thickness, growth kinetic and hardness of boride layers were investigated. Experimental results showed that the boride layers were composed of a continuous TiB 2 top-layer and a TiB nano-whisker sub-layer. The maximum thickness of boride layers of TiB 2 and TiB were 2.24 ± 0.49 μm and 15.63 ± 6.97 μm, respectively. The activation energy of boron atom for the SPS boride process was calculated to be 386.49 kJmol −1 for the TiB 2 layer and 343.57 kJmol −1 for the TiB layer, which indicates that the SPS can provide enough energy that required in the surface treatment. Boride layers can grow well at a vacuum level of 6 Pa in the SPS. The borided Ti is about six times the hardness of the pure Ti. Boron atoms in the TiB 2 powders were activated by the high temperature and plasma, then reacted with Ti to form TiB nano-whiskers. The holding time of the present method was significantly shorter than other boriding processes. This SPS process provides a new approach for boriding of Ti and its alloys. • Ti boride layer by SPS was composed of TiB 2 and TiB nano-whisker. • The growth of titanium boride layers was enhanced significantly by SPS. • Six times increased hardness of Ti was achieved with short holding time in SPS. • The growth kinetic of boride layers is a diffusion-controlled model.

Microstructure and properties of metal parts remanufactured by laser cladding TiC and TiB2 reinforced Fe-based coatings

Laser cladding process, an efficient surface remanufacturing method, has become a research hotspot in recent years. Herein, in situ titanium carbide (TiC) and titanium diboride (TiB2) reinforced composite coatings were fabricated on the surface of damaged carbon steel to improve the hardness and wear resistance of remanufactured parts. Effects of addition of 5B4C and 15Ti (in wt.%) powder on morphology, phase composition, microstructure, and mechanical properties of specimens were comprehensively investigated. Results revealed that milled groove could be effectively filled with composite coating, which formed good metallurgical bonding with the substrate. Furthermore, sequentially precipitated in situ synthesized phases including TiC, TiB2, Cr3C2, Fe2B, and Fe3C in composite coating could continuously increase nucleation sites and further refine grains. Moreover, uniformly distributed reinforcements effectively weakened the directivity of heat flow during solidification process and promoted columnar to equiaxed transition. Mechanical properties illustrate that micro-hardness of composite coating with 961.94 HV0.3 is 4.14 and 5.04 times, and corresponding volume loss is 7.8 and 2.8 less than those of 316 L coating and standard 45 steel, respectively. This study indicates that in situ formed ceramics reinforced composite coating can act as an ideal candidate for remanufacturing damaged parts, and further improve their wear resistance.

Synthesis and characterization of TiBx (1.2 ≤ x ≤ 2.8) thin films grown by DC magnetron co-sputtering from TiB2 and Ti targets

Titanium boride, TiBx, thin films were grown by direct current magnetron co-sputtering from a compound TiB2 target and a Ti target at an Ar pressure of 2.2 mTorr (0.3 Pa) and substrate temperature of 450 °C. While keeping the power of the TiB2 target constant at 250 W, and by varying the power on the Ti target, PTi, between 0 and 100 W, the B/Ti ratio in the film could be continuously and controllably varied from 1.2 to 2.8, with close-to-stoichiometric diboride films achieved for PTi = 50 W. This was done without altering the deposition pressure, which is otherwise the main modulator for the composition of magnetron sputtered TiBx diboride thin films. The film structure and properties of the as-deposited films were compared to those after vacuum-annealing for 2 h at 1100 °C. As-deposited films consisted of small (≲50 nm) randomly oriented TiB2 crystallites, interspersed in an amorphous, sometimes porous tissue phase. Upon annealing, some of the tissue phase crystallized, but the diboride average grain size did not change noticeably. The near-stoichiometric film had the lowest resistivity, 122 μΩcm, after annealing. Although this film had growth-induced porosity, an interconnected network of elongated crystallites provides a path for conduction. All films exhibited high hardness, in the 25–30 GPa range, where the highest value of ~32 GPa was obtained for the most Ti-rich film after annealing. This film had the highest density and was nano-crystalline, where dislocation propagation is interrupted by the off-stoichiometric grain boundaries.

Development of Ni-base metal matrix composites by powder metallurgy hot isostatic pressing for space applications

In this work, near-net-shape powder metallurgy hot isostatic pressing (NNS PM HIP) of Ni-base metal matrix composite (Ni-MMC) was developed to improve the hardness and wear properties of turbopumps mechanical seals. Silicon carbide (SiC) and titanium diboride (TiB2) fine powders were used as reinforcements with different ratios to improve the hardness and consequently the tribological properties of the developed Ni-MMC material. Powder characterisation was performed on the blended powders to check the homogeneity of the mixed powders. The hot isostatically pressed (HIPed) Ni-MMC microstructures were analysed using scanning electron microscope (SEM) and energy dispersive X-ray spectroscopy (EDS) techniques. The HIPed material showed a fully dense microstructure with a continuous network of ceramic reinforcement particles at the prior particle boundaries (PPBs). Furthermore, microhardness tests were performed on IN625, IN625-SiC and IN625-TiB2 to understand the impact of the reinforcement on the microhardness. It was demonstrated that the volume percentage of ceramic reinforcement in the IN625 matrix plays a crucial role in achieving higher hardness by increasing the fraction of hard phases appearing in the microstructure of the developed Ni-MMC material. The final part of the work focuses on the canister design and manufacture of a near-net-shape (NNS) mechanical gas seal using IN625 based MMC to demonstrate the feasibility of manufacturing mechanical seals through the NNS PM HIP technique. Overall, IN625 based MMCs resulted in a drastic improvement in tribological properties if compared to the base material. Furthermore, the employment of the PM HIP consolidation technique resulted in a fully dense and homogeneous microstructure, highlighting the potentials of PM HIP in the generation of novel composite materials.

Nanoparticulate reinforced composites and their application to additively manufactured TI6AL4V for use in the aerospace sector

Metal matrix composites possess good mechanical properties at high temperatures making them good candidates for components that operate in conditions of high temperatures where they have to withstand static creep and cyclic fatigue loads. The mechanical properties of Ti6Al4V including hardness, strength, modulus of elasticity, and wear resistance can be enhanced with nano particulates to obtain lighter and stronger materials that can function at elevated temperatures. This paper starts with a brief background on composite materials and then turns to analysis of carbon nanotubes, titanium carbide, silicon carbide, titanium boride, titanium diboride, and titanium nitride nano particulate materials as candidates for the reinforcement for Ti6Al4V to form composites for aerospace applications. Based on a comparison of their physical properties of melting point, coefficient of thermal expansion, density and mechanical properties of strength, Young's modulus and hardness all obtained from literature, the paper narrows down on multiwalled carbon nanotubes and titanium diboride as the preferred nano composites for this use. Presently, experimental work is under way to determine optimum process parameters for additively built carbon nanotube/Ti6Al4V composites that will be used to build three-dimensional specimens for testing to determine their mechanical properties. This is expected to clarify the value of incorporating the carbon nanotubes in the Ti6Al4V matrix with respect to selected mechanical properties. Future work is envisaged on additively build titanium diboride/Ti6Al4V composites to the same end and in order to determine which of the two nano particles is best in enhancing the mechanical properties of Ti6Al4V.

Investigating the effect of ceramic-reinforcements on aluminum matrix fabricated by pulsed electric current sintering

Titanium diboride and dinickel boride were used to reinforce the aluminum matrix via a Turbula mixer at 101 rpm. The admixed powders were consolidated by using the pulsed electric current sintering. The powders and sintered samples' microstructural analysis was determined by optical microscopy (OM) and scanning electron microscopy (SEM). Furthermore, the phase identification of the samples was evaluated with an X-ray diffractometer (XRD). The relative density of the sintered Al sample was observed to be 99.07%. The addition of ceramic reinforcements improved the relative density from 99.07% to 99.64%. The microhardness of sintered samples increased from 34.14 HV1 to 37.50 HV1 due to the ceramic reinforcements.

Модифицирование наноразмерными частицами нитрида кремния материалов на основе системы Ti – B – Fe, полученных методом СВС-экструзии

Compact ceramic SHS-electrode materials based on titanium diboride modified with silicon nitride nanoparticles have been obtained by SHS-extrusion. The phase composition, structure, and physicomechanical properties of the obtained materials have been studied. The results of scanning electron microscopy showed that, in the modified samples, grain refinement of the main phase of titanium diboride is observed, as well as a change in the phase composition of the material. With the introduction of 5 wt. % nanosized particles of silicon nitride, in addition to the main wear-resistant phase TiB2, the formation of phases is observed: TiN, Fe2B and TiSi2 located in the FeTi intermetallic matrix. The average grain sizes of TiB2 and TiN are 0.5 – 2 mm and 2 mm, respectively. With the addition of 10 wt. % Si3N4, the structure of the material consists of TiB2 and TiN phases uniformly distributed in the FeTi intermetallic matrix, and a small amount of Si and B solid solutions. The TiB2 grain size does not exceed 0.5 – 1 mm, and the TiN phase has an average grain size about 0.5 – 1.5 mm. It is shown that the obtained modified ceramic SHS-electrode materials have higher microhardness and hardness compared to the material without Si3N4 additives.

Wear resistance study on HVOF based SiC and TiB2 ceramic coating for AH36 steel for marine based thermal applications

ASTM AH36 steel has been a primary material used for marine-based construction and applications. It is also a primary material employed in boilers and thermal-based equipment. The material is known for versatility and reliability in marine environments. However, the steel has an inherent limitation for wear resistance when subjected to adverse conditions during operation by the marine ecology as well as abrasive materials when being in thermal operation. This has been a major reason for services and these problems can be mitigated by improving the hardness, chemical inertness and adhesion to the substrate. Silicon Carbide (SiC) and Titanium Diboride (TiB2) are noted for their hardness and ecologically inert behaviour. The steel surface has been coated with these ceramic materials to improve the wear resistance. The coating is provided by the High-Velocity Oxy-Fuel (HVOF) technique. A microstructural, mechanical and wear analysis is performed on SiC, TiB2 and Mixture of 80 %SiC-20 %TiB2 coated specimens to analyze the surface modifications. Based on the pin on disc test results it can be observed that the application of Silicon Carbide and Titanium Diboride coatings has shown an improvement in wear resistance by reducing a wear loss by 1/8th, 1/6th and 1/10th respectively against the uncoated specimen. This increase in wear resistance is attributed to the improvement in the hardness of the surface by formation of harder compounds and additional phases during HVOF process. This indicates that inert material-based surface modifications can be an ecofriendly and effective way to improve the wear resistance in marine steels.

Analysis of Spectroscopic, Morphological Characterization and Interaction of Dye Molecules for the Surface Modification of TiB2 Nanoparticles

Nanoparticles of titanium diboride (TiB2) coated with a conductive polymer and subjected to an oxidizing agent was carried out in this research. TiB2 nanoparticles coated with polypyrrole (PPy) were studied using XRD and TEM techniques. Nitrogen adsorption and desorption properties of nanoparticles are covered with modified polypyrrole to understand better the surface zone, structural features, and pore geometries of the nanoparticles. The water‐based hazardous anionic Congo red (CR) dye was removed using polypyrrole‐coated titanium diboride (PPy@TiB2) nanoparticles. Numerous cutting‐edge experimental techniques, including FTIR, FE‐SEM, EDXS, and element mapping analysis, were used to confirm the CR color’s adhesion to the PPy@TiB2 nanoadsorbent study. While conducting batch experiments, coated TiB2 nanoadsorbents with polypyrrole enhanced the adsorption behaviour. One of the factors evaluated in the adsorption tests was pH; another was contact time, and a third was dose. At pH = 4, 98.75% of Congo red dye was detached using 60 mg of PPy‐coated TiB2 nanoadsorbent. Several sorption‐desorption cycles were performed on this nanoadsorbent to determine its reusability. An excellent adsorption capacity for water treatment is reported in PPy‐coated TiB2 nanoadsorbent.

Optimization on Wear Rate of AA2219/Nanographite/TiB2/Si3N4 Hybrid Composites Using Taguchi Process

The various following reinforcements like nanographite, titanium diboride (TiB2), silicon nitride (Si3N4), and aluminum 2219 have all been investigated in this study. Current research suggests that TiB2 and graphite may be a suitable reinforcement for Al2219 alloy. The stir casting process was used to make reinforced composites on unreinforced Al2219. Compared to the unreinforced Al2219, the TiB2 and nanographite‐reinforced hybrid composites showed the exceptional wear resistance (30%) at 175°C. Matrix strengthening kinetics is improved at 175°C when TiB2 and nano‐Gr reinforcement particles are present. To obtain a p value less than 1% and an absolute relative error of less than 1%, an artificial neural network was employed.

Mechanisms of Molding, Phase Formation, and Structuring of Materials Based in Titanium Borides under the Conditions of Combustion Processes and High-Temperature Shear Deformation

Mechanisms of Molding, Phase Formation, and Structuring of Materials Based in Titanium Borides under the Conditions of Combustion Processes and High-Temperature Shear Deformation

Titanium Boride and Titanium Silicide Phase Formation by High Power Diode Laser Alloying of B4c and Sic Particles with Ti: Microstructure, Hardness and Wear Studies

Titanium Boride and Titanium Silicide Phase Formation by High Power Diode Laser Alloying of B4c and Sic Particles with Ti: Microstructure, Hardness and Wear Studies

Distribution of titanium diboride microparticles introduced into aluminum ingot by MHD-stirring of a crystallizing melt

Distribution of titanium diboride microparticles introduced into aluminum ingot by MHD-stirring of a crystallizing melt

Interaction of Titanium Diboride with Nickel and Ni–20% Cr Alloy (Nichrome)

Interaction of Titanium Diboride with Nickel and Ni–20% Cr Alloy (Nichrome)

Salt spray corrosion study on aluminium metal matrix composites (AMMCs) prepared by powder metallurgy route

Metal Matrix Composites (MMCs) production is one of the major role in the industries, the Powder Metallurgy method is suitable for production of MMCs at correct proportional rate. Aim of this experimental work is prepare the Aluminium Metal Matrix Composites (AMMCs) by powder metallurgy route. Aluminium alloy AA7085 is selected for this experimental work due to their extreme mechanical properties. Strengthening of this aluminium alloy is carried out by addition of Titanium Diboride (TiB2) with different weight percentage. AMMCs are prepared through powder metallurgy route and the process parameters of the P/M are optimized with the aid of Taguchi approach. Parameters are selected for this experimental work is milling time (3 hrs, 4 hrs and 5 hrs), compaction pressure (200 MPa, 250 MPa and 300 MPa) and sintering temperature (550 °C, 600 °C and 650 °C). Minimum corrosion rate is obtained as 0.00092 mm/year, milling time is highly influenced in the corrosion rate analysis.