TiC Metal Matrix Research Articles

New Approach for Manufacturing Ti–6Al–4V+40%TiC Metal-Matrix Composites by 3D Printing Using Conic Electron Beam and Cored Wire. Pt. 2: Layered MMC/Alloy Materials, Their Main Characteristics, and Possible Application as Ballistic Resistant Materials

Bilayer samples comprised of hard metal-matrix composite top layer and ductile 10 mm Ti–6Al–4V plate are produced with 3D printing by conical electron-beam method using specially prepared core (powder) wire that allows forming hard top layer of metal-matrix (Ti–6Al–4V) composite (MMC) reinforced by means of fine TiC particles with thickness up to 4 mm. Ballistic tests performed with 7.62×51 AP ammunition show a good ballistic resistance of this protective structure, i.e., it is not perforated. Only minor penetration and partial fracture are occurred exclusively in the surface MMC layer. Either no traces of plastic deformation are found at the boundary with the base layer or inside it that indicates that the MMC layer absorbs the entire impact energy of the projectile. Based on studies of the fine structure and texture of the interface between the layers, a reasonable assumption is made that wavy geometry of MMC layer provides additional deflection and scattering of stress waves generated during impact. Comparing the results of ballistic tests of various metallic materials, it is concluded that the 3D-printed bilayer material consisting of the upper Ti–6Al–4V + 40% TiC layer and the base Ti–6Al–4V layer has an undeniable advantage in ballistic performance when it is tested with cartridges of this type.

New Approach for Manufacturing Ti–6Al–4V+40%TiC Metal-Matrix Composites by 3D Printing Using Conic Electron Beam and Cored Wire. Pt. 1: Main Features of the Process, Microstructure Formation and Basic Characteristics of 3D Printed Material

In this paper, a new approach for additive manufacturing metal-matrix composites based on Ti–6Al–4V titanium alloy reinforced with titanium carbide particles, as well as layered structures consisted of such composite and Ti–6Al–4V alloy layers is considered. The approach is based on 3D printing with a conical electron beam using a special cored wire, whose composition corresponds to metal-matrix composite. The issues of production such a wire, the features of the 3D printing process, when using it, as well as the features of formation of the microstructure and phase composition of the printed composite material are described. The issues of titanium-carbide particles’ wetting with Ti–6Al–4V melt during process of 3D printing, as well as possible thermogravitational effects (floating or drowning) for solid TiC particles within the melt are considered in detail with additional experiments. The influence of individual components of the wire composition on the formation of the microstructure and its uniformity over the cross section of the printed layer is shown. The possibility of controlling the formation of homogeneous structural state and obtaining sufficiently high values of the hardness (of above 600 HV) of the metal-matrix composite layer printed on the Ti–6Al–4V baseplate is shown.

Processability of thin-powdered Inconel X750 and TiC metal matrix composite by laser-directed energy deposition

The processability of pure Inconel X750 and Inconel X750 mixed with 15 vol. % of titanium carbide particulate through laser-directed energy deposition (l-DED) was evaluated. The powders used had a particle size in a range unusual to l-DED processing (0.18–24.05 μm); this case study presents difficulties in processing thin quadri-modal powder and describes possible measures to mitigate them, while also reporting, likely for the first time, on the l-DED processing of Inconel X750 and such related metal matrix composite (MMC). The choice in reinforcement particle size and composition aimed for a reduction in material density and insertion of additional reinforcement mechanisms. Both powders used were analyzed in an FT4 rheometer and compared to reference Inconel 625 powder. l-DED was made viable, but results show that the powders tested here represent a lower limit for the rheological properties accepted by usual l-DED systems. A methodology to quantify the stability of a given processing condition is presented and validated, also indicating that low powder flows are recommended when processing powders of this sort. Inconel X750 demonstrated sensibility to oxidation during processing as depletion of Al and Ti was detected in the deposits. Neither the MMC nor the pure material cracked or showed excessive porosity.

Studies of kerf width and surface roughness using the response surface methodology in AA 4032–TiC composites

A substantially developed machining process, namely wire electrical discharge machining (WEDM), is used to machine complex shapes with high accuracy. This existent work investigates the optimization of the process parameters of wire electrical discharge machining, such as pulse on time ( Ton), peak current ( I), and gap voltage ( V), to analyze the output performance, such as kerf width and surface roughness, of AA 4032–TiC metal matrix composite using response surface methodology. The metal matrix composite was developed by handling the stir casting system. Response surface methodology is implemented through the Box–Behnken design to reduce experiments and design a mathematical model for the responses. The Box–Behnken design was conducted at a confident level of 99.5%, and a mathematical model was established for the responses, especially kerf width and surface roughness. Analysis of variance table was demarcated to check the cogency of the established model and determine the significant process. Surface roughness attains a maximum value at a high peak current value because high thermal energy was released, leading to poor surface finish. A validation test was directed between the predicted value and the actual value; however, the deviation is insignificant. Moreover, a confirmation test was handled for predicted and experimental values, and a minimal error was 2.3% and 2.12% for kerf width and surface roughness, respectively. Furthermore, the size of the crater, globules, microvoids, and microcracks were increased by amplifying the pulse on time.

Manufacturing Fe–TiC metal matrix composite by Electron Beam Powder Bed Fusion from pre-alloyed gas atomized powder

Fe–TiC metal matrix composite (MMC) material is fabricated by EB-PBF (Electron Beam Powder Bed Fusion) additive manufacturing technique. Herewith, gas atomized model alloy powder containing in-situ formed reinforcement phase is utilized. Powder properties (i.e., particle size distribution, morphology, flowability, tap, and apparent density) are discussed in relation to composite powder applicability for EB-PBF. As a result, samples with over 99% density were fabricated. Cross-section samples investigated via SEM (scanning electron microscopy) and EBSD (electron back-scattered diffraction analysis) reveal homogeneously distributed submicron TiC reinforcements of two morphologies – blocky TiC precipitates and fine needle-shaped ones. Fabricated composite demonstrates enhanced tensile strength of 537 MPa, while preserving the sufficient level of ductility (35.0%), which correlates with the low hardness of 153.9 HV10. Additionally, heat treatment of as-built samples is investigated by implementing differential scanning calorimetry (DSC), dilatometry analysis, and austenitization-water-quenching techniques. Applied heat treatment induces a significant grain refinement, which increases the hardness of treated samples up to 246.3 HV10 by water quenching, while TiC precipitates undergo minor changes in morphology and size. Fabricated MMC material demonstrates the successful application of the gas atomized powder with an in-situ formed carbide reinforcement phase for additive manufacturing.

Manufacturing Fe–TiC Composite Powder via Inert Gas Atomization by Forming Reinforcement Phase In Situ

Fe–TiC metal matrix composite powder is manufactured applying vacuum inert gas atomization technique. The TiC reinforcement phase forms in situ within spraying of the Fe‐based molten metal preliminary alloyed with 1 wt% [C] and 4 wt% [Ti]. Alloying strategy, homogenization time, and spraying temperature are varied for three conducted atomization experiments in this study. Medium particle size (d50) lies in a range of 41–55 μm for obtained spherical powders. Scanning electron microscopy (SEM) analysis and Energy‐dispersive X‐ray spectroscopy (EDX) mapping of powder cross‐section samples reveal well‐dispersed submicron TiC precipitates of two different morphologies—primary‐blocky and eutectic‐plate‐shape carbides. The amount of precipitates and their morphology depend on the particle size. Namely, coarser powder particles tend to have more primary carbides that are presumably formed already in liquid droplets. Meanwhile, TiC precipitation in finer particles up to ≈25 μm is completely suppressed due to an extremely high cooling rate. Difficulties of the Fe–Ti–C melt atomization (e.g., formation of a semiliquid slag layer, loss of TiC forming elements, the presence of large precipitates in a powder) are discussed considering the thermodynamic analysis of this system and Fe–TiC remelting experiments conducted on a hot stage microscope.

Microstructural Characterization of TiC-White Cast-Iron Composites Fabricated by In Situ Technique.

High-chromium white cast-iron specimens locally reinforced with TiC–metal matrix composites were successfully produced via an in situ technique based on combustion synthesis. Powder mixtures of Ti, Al, and graphite were prepared and compressed to fabricate green powder compacts that were inserted into the mold cavity before the casting. The heat of the molten iron causes the ignition of the combustion reaction of the reactant powders, resulting in the formation of the TiC by self-propagating high-temperature synthesis. The microstructure of the resultant composites and the bonding interfaces was characterized by scanning electron microscopy and energy dispersive spectroscopy (SEM/EDS), X-ray diffraction (XRD), and transmission electron microscopy (TEM). The microstructural results showed a good adhesion of the composite, suggesting an effective infiltration of the metal into the inserted compact, yet a non-homogeneous distribution of the TiC in the martensite matrix was observed. Based on the results, the in situ synthesis appears to be a great potential technique for industrial applications.

Mechanical and tribology properties of Al-4.5%Cu-5%TiC metal matrix composites for light-weight structures

Aluminum alloy based metal matrix composites has an important role in the field of automobile, aerospace, military and structural applications due to their enhanced mechanical and tribological properties as compared to base aluminum alloys. To enhance the mechanical and tribological properties suitable reinforcement has to be added to the aluminum alloy to fabricate the composites. Present investigation deals with mechanical and wear properties enhancement of Al-4.5%Cu alloy reinforced with 5%TiC in-situ metal matrix composite (MMC) through friction stir processing (FSP) techniques suitable for automobile and aerospace applications. The fabricated composites (Al-4.5%Cu/5%TiC) were hot rolled to remove defects such as porosity and voids. Experiments were conducted using pin-on-disc apparatus against abrasive paper by varying the applied load, sliding distance. The experimental results revealed that the weight loss and co-efficient of friction increases with increase in applied load and sliding distance. The MMC material, Al-4.5%Cu/5%TiC exhibited enhanced ultimate strength and hardness as compared to Al-4.5%Cu alloy. The contribution of TiC as reinforcement is clearly observed with an increase in hardness of the composite as compared with the matrix material. Scanning electron microscopy (SEM) and XRD analysis was done to study the microstructure of the fabricated materials.

Processing, Sintering and Performance of WC-Co-Near-Nano TiC Metal Matrix Composites

Processing, Sintering and Performance of WC-Co-Near-Nano TiC Metal Matrix Composites

Investigations on microstructure, mechanical, and tribological behaviour of AA 7075–x wt.% TiC composites for aerospace applications

This research work was dedicated to prepare AA 7075/(0, 2.5, 5 and 7.5wt.%) TiC metal matrix composites through stir casting route. The manufactured composites were effectively characterized using various techniques such as X-ray diffraction, and advanced electron microscopes. The mechanical properties by the flexural strength and hardness results had performed and investigated elaborately. Further, the tribological properties in terms of the wear resistance and the coefficient of friction was also done and demonstrated clearly. The dispersion of TiC ceramic particles and its embedding over the ductile Al 7075 matrix was successfully obtained which exhibited excellent mechanical and surface behaviour with the function of TiC particles when compared to monolithic Al 7075 alloy. These results were due to the particulate strengthening of hard TiC ceramic particle over the soft ductile phase. In addition, X-ray diffraction results ensured the manufacturing of Al 7075-xwt.% TiC metal matrix composites successfully and no other inter-metallic phases were observed.

Selective Laser Melting process optimization of Ti–Mo–TiC metal matrix composites

Selective Laser Melting (SLM) was used to process a powder mixture of CP Ti, 6.5 wt% Mo and 3.5 wt% Mo2C. The process parameters were optimized to obtain full-density, crack free parts. After the in situ decomposition of Mo2C in favor of the formation of TiC, the material consisted of a homogeneous dispersion of submicrometer sized TiC platelets in a β-(Ti,Mo) matrix exhibiting a high hardness up to 550 HV and compressive yield stress of 1164 ± 37 MPa. The microstructure and mechanical properties could be tailored by variation of the process parameters within the high-density processing window, as well as through post-process heat treatments.

Effect of hardness and CNC milling roughness behaviour of A6061 aluminium alloy reinforced with TiC metal matrix composite

Effect of hardness and CNC milling roughness behaviour of A6061 aluminium alloy reinforced with TiC metal matrix composite

Modeling the dry sliding wear behavior of Cu-4wt%Ni-TiC composites using response surface methodology

The present paper intends to optimize certain process parameters on the wear and friction properties of Cu-4 wt% Ni- x wt% TiC (x = 0, 2 and 4 wt%) metal matrix composites by using response surface methodology (RSM). The dry sliding wear test was conducted using a pin-on-disc with different process parameters of applied load, weight percentage of TiC particles and sliding distance as process variables. Analysis of variance was applied to check the adequacy of the developed model. Mathematical models were developed to investigate the influence of process parameters on the responses at 95% confidence level. Developed surface and contour plots depicted the effect of main parameters and its interactions on the responses.

Influence of TiC addition on the surface roughness during turning of AA 7075 alloy processed through stir-casting

This research work had focused on manufacturing AA 7075/(0, 2.5, 5 and 7.5 wt%) TiC metal matrix composites through stir casting route. The manufactured composites had effectively characterized using the optical microscope. It had observed from the optical microstructures that the uniform distribution of TiC ceramic particles and its embedding over the ductile AA 7075 matrix had successfully obtained which exhibited excellent mechanical (218 HRC for 7.5 wt% TiC composite) and machining behavior with the function of TiC particles when compared to monolithic AA 7075 alloy. There had a grain refinement in the composites due to TiC particles addition. The machinability of experiments had conducted by varying the cutting speed, the feed rate, the depth of cut and the tool nose radius. The surface roughness had measured and the results had indicated that AA 7075–7.5 wt% TiC ex-situ composites had exhibited a lower value of surface roughness which had expected to high-strength in the matrix that produced immediate shearing action when compared to other samples. Further, the tool nose radius had played a major role in the surface roughness in which higher value of tool nose radius (0.8 mm) sample had shown improved surface finish.

Investigation Of Surface Roughness In Turning of In-situ Al6061-TiC Metal Matrix Composite By Taguchi And Prediction Of Response by ANN

In the present study turning experiments, are carried out on in-situ, developed Al6061-10 Wt % TiC metal matrix composite rod for to find out the optimal combination of process parameters for to achieve optimal surface roughness. The experimental design is planned by using L27 orthogonal array, and the results are analysed by using Taguchi’s lower the best signal to noise ratio. The analysis of signal to noise ratios shows that the optimal surface roughness value is obtained at higher cutting speeds and lower feed rate and depth of cut. ANOVA is performed to know the percentage contribution of cutting speed, feed rate and depth of cut. ANOVA results shows that among the three process parameters cutting speed has the most influence on surface roughness. An artificial neural network model is developed to predict the surface roughness. The network is trained by supplying input and output values. The predicted surface roughness values from ANN model are closely near to the experimental results.

Modeling of wear process parameters of in-situ RZ5-10wt%TiC Composite using artificial neural network

In this paper modeling of wear process parameters of in-situ RZ5-10wt%TiC metal matrix composite investigated. The RZ5-10wt%TiC composite has fabricated by argon assisted self-propagating high-temperature method. It is used in automotive, aerospace application to protect parts against wear. The pin on disc machine has used for the wear test. It has performed by varying input as the applied load and sliding distance. The coefficient of friction and weight loss considered as the output of the test. The results showed improvement in wear resistance of the RZ5-10 wt% TiC composite compares to the unreinforced alloy. Further, modelling of wear resistance of RZ5-10 wt% TiC composites were done using the back propagation neural network with Broyden–Fletcher–Goldfarb–Shanno(BFGS)algorithm. The ANN model trained using experimental data. After the completion of training process test data were used to check the system accuracy. It found success in the prediction of wear process parameters of RZ5-10wt%TiC composite. The results have shown that the values of wear process parameters obtained from ANN are very close to the experimental values. Also, it is useful compare to time-consuming experimental processes.

Multiobjective optimization of in situ process parameters in preparation of Al-4.5%Cu–TiC MMC using a grey relation based teaching–learning-based optimization algorithm

In modern in situ composite fabrication processes, the selection of optimal process parameters is greatly important for the preparation of best quality metal matrix composite. For achieving high-quality composite, an efficient optimization technique is essential. The present study explores the potential of a new robust algorithm named teaching–learning-based optimization algorithm for in situ process parameter optimization problems in fabrication of Al-4.5%Cu–TiC metal matrix composite fabricated by stir casting technique. Optimization process is carried out for optimizing the in situ processing parameters i.e. pouring temperature, stirring speed, reaction time for achieving better mechanical properties, i.e. better microhardness, toughness, and ultimate tensile strength. Taguchi’s L25 orthogonal array design of experiment was used for performing the experiments. Grey relational analysis is used for the conversion of the multiobjective function into a single objective function, which is being used as the objective function in the teaching–learning-based optimization algorithm. Confirmation test results show that the developed teaching–learning-based optimization model is a very efficient and robust approach for engineering materials process parameter optimization problems.

Online assessment of TiC decomposition in laser cladding of metal matrix composite coating

Decomposition of ceramic particles in metal matrix composite coatings developed by laser cladding process is one of the major problems that deteriorate the mechanical properties of coating. Further, a large number of process parameters involved in laser cladding makes the process optimization difficult. Therefore, a study was undertaken to assess the condition of TiC particles in the molten pool by monitoring the thermal history using an IR pyrometer. It was observed that with the increase of molten pool lifetime, a reaction layer is created between TiC particles and metal matrix which improves their bonding. However, with further increase in the molten pool lifetime TiC particles were found to decompose completely forming dendritic structure in the metal matrix through heterogeneous nucleation and subsequent crystallization during the solidification process. This results in a change of the solidification shelf slope which can be used as an effective signature to assess the TiC particle condition in molten pool online without performing any destructive test. The modified structure of metal matrix exhibited brittle nature which increased the wear rate due to fracture and spalling of coating during the wear test.

Experimental Analysis on Three Body Abrasive Wear Behaviour of Stir Cast Al LM 25/TiC Metal Matrix Composite

In this paper, the abrasive wear behavior of Al LM 25/10 wt% TiC metal matrix composite has been studied experimentally. The composite specimens were fabricated using stir casting technique. Microstructural evaluation revealed uniform distribution of reinforcement particles throughout the matrix. Abrasive wear experiments were designed for different values of load, speed and time through response surface methodology and were performed using three body abrasion tester. Surface plots for wear rate against all combinations of parameters revealed that wear rate increased with increasing load and time, but decreased with increasing speed. The generated regression equation established proper relation between parameters and wear rate, confirming the accuracy of the developed model. The results of optimization of process parameters revealed that a minimum wear rate of 0.00104 mm3/Nm was obtained at 27 N, 139 rpm and 3 min. Scanning electron microscope analysis results substantiated that wear rate was comparatively more at higher loads.

Microstructure and mechanical behaviour of in situ fabricated AA6061–TiC metal matrix composites

AA6061–TiC composites were developed by in situ reaction of molten AA6061 alloy with potassium hexafluorotitanate salt and pure graphite at a temperature of 900°C. The in situ composites were subjected to hot forging at 500°C and uniform strain rate of 0.0115mms−1 with degree of deformation of 65%. Both cast and forged in situ composites were subjected to grain size analysis and scanning electron microscopy studies to study the dispersion of TiC particles. Mechanical properties like Brinell hardness and tensile properties were evaluated to measure the effect of TiC particles on the AA6061 matrix. Microstructure of forged composites revealed uniform dispersion of TiC particles without forming any lumps at any particular regions. Brinell hardness and tensile strength of cast and forged in situ composites increased with increasing TiC particle content. The improved mechanical properties were attributed to good dispersion of TiC particles, grain refinement of the matrix and dislocation strengthening. Every fracture developed in cast ones was due to inter-dendritic cracking while in the case of forged ones it had mixed mode of fracture with dominating ductile nature.