Eutectic TiC Research Articles

Effect of Nb addition on microstructure and mechanical properties of TiC/Ti-7.8Cr composites

The morphology of TiC is not difficult to control when the titanium matrix composites with high TiC content are prepared by the melting-casting method. TiC tends to grow into dendrites, increasing the brittleness of the Ti matrix composites. In this study, in-situ TiC-reinforced titanium matrix composites with varying Nb content were prepared by adding Nb. The effects of adding Nb on the microstructure evolution and mechanical properties of the composites were studied. The results show that with the increase of Nb content, the grain size of the composites decreased gradually from 276 μm to 122.8 μm, the primary TiC content decreased, and the eutectic TiC content increased. On the other hand, the orientation relationship between TiC (111)//β-Ti (110) and TiC [10 1‾]//β-Ti [1‾ 11] was studied by HTEM. The two-dimensional mismatch of TiC (111)//β-Ti (110) is only 9.06 %, which means that TiC can be used as a nucleation particle of β-Ti. Furthermore, there was a gradual increase in the Rockwell hardness of the composites as the Nb content was incrementally raised from 0 wt% to 1.5 wt%, with the highest recorded value being 47.4 HRC. Notably, when the Nb addition reached 1.0 wt%, the composite achieved its maximum tensile strength of 1352.9 MPa, signifying a 69 % enhancement compared to the absence of Nb. This is due to the combined effect of fine grain strengthening, solution strengthening, and second-phase strengthening in the composites. It introduces a novel approach to regulate the in-situ formation of TiC morphology during the preparation of titanium matrix composites through melting and casting.

Thermal analysis and microstructure evolution of TiC/Ti6Al4V functionally graded material by direct energy deposition

Metal/ceramic functionally graded materials (FGMs) have attracted significant attention due to their ability to combine the unique mechanical properties of metals with the high-temperature resistance of ceramics while mitigating the thermal stresses arising from the differences in their thermal expansion coefficients. In this study, the directed energy deposition (DED) technology is applied to manufacturing TiC/Ti6Al4V FGMs with TiC contenting up to 50 wt%. However, the variations in composition gradients and the complex thermal cycling processes lead to difficulties in the microstructure evolution and control. Therefore, a combined approach involving finite element (FE) simulations and experiments was employed to investigate the mechanisms underlying microstructural transformations under various gradient thermal cycles. The results showed that the morphology of TiC in the FGM from top to bottom is as follows: coarse dendritic TiC + unmelted TiC, granular primary TiC + underdeveloped dendritic TiC, chain-like eutectic TiC + granular eutectic TiC. Meanwhile, both α-Ti and β-Ti exhibited equiaxed transformation, with their sizes decreasing continuously with the gradient. This is due to the strong orientation relationship between TiC particles and the titanium matrix, allowing α-Ti and β-Ti to form non-uniform nucleation within the TiC phase. In addition, the chain-like eutectic TiC and dendritic primary TiC showed a certain degree of fragmentation and granulation after undergoing thermal cycling. The microstructural evolution mechanism in different gradient regions during the DED process under the coupling effect of thermal cycling and ceramic composition was clarified by combining the FE simulation results. The specimen at the bottom of FGMs exhibits strong and ductile (tensile strength: 1296 MPa, elongation: 7.17 %), which are mainly attributed to the Hall Petch strength and solid solution strengthening. The brittle phase of dendritic TiC and unmelted TiC under high gradients leads to decreased tensile properties.

Microstructure and properties of (diamond + TiC) reinforced Ti6Al4V titanium matrix composites manufactured by directed energy deposition

In this study, (diamond + TiC) reinforced Ti6Al4V titanium matrix composites (DT-TMCs) were fabricated using the directed energy deposition (DED) technique to enhance multiple properties of the Ti6Al4V alloy. The phase composition, microstructure, microhardness, wear resistance, and thermal conductivity of the composites were investigated. The findings demonstrate that the DT-TMCs consist of diamond, in-situ formed TiC (including eutectic TiC and primary TiC), α-Ti and β-Ti. The formation of in-situ TiC is attributed to the partial dissolution of the diamond into the Ti6Al4V matrix during the DED process. The superior hardness of in-situ TiC, compared to that of Ti6Al4V alloy, plays a pivotal role in enhancing the overall hardness of the DT-TMCs. Owing to the high hardness and excellent thermal conductivity of diamond, the wear resistance and thermal conductivity of the DT-TMCs are superior to those of the unmodified Ti6Al4V alloy. With the diamond volume fraction increasing from 0% to 15%, the microhardness of the DT-TMCs raises from 333.99 HV0.2 to 438.15 HV0.2, the wear rate decreases from 207.514 × 10−5 mm³·N−1·m−1 to 2.256 × 10−5 mm³·N−1·m−1, and the thermal conductivity increases from 6.686 W·m−1·K−1 to 13.613 W·m−1·K−1. Additionally, the in-situ TiC exhibits superior thermal conductivity compared to the Ti6Al4V alloy, which also contributes to the improved thermal conductivity of the DT-TMCs.

Study on the precipitation mechanisms of TiC particles in steel matrix composites fabricated by eutectic solidification

The precipitation mechanisms of TiC eutectic particles in steel matrix composites prepared by eutectic solidification are studied through thermodynamic calculations and experimental analyses. The results indicate that the eutectic TiC particles begin to precipitate when the concentrations of Ti and C in the residual molten steel reach a eutectic point during the solidification process. The mass fractions of Ti and C in SMCs play significant roles in the precipitation time, particle characteristics and precipitation mechanism characteristics of TiC eutectic particles. When the mass fractions of Ti and C in SMC are low, TiC particles precipitate in the form of divorced eutectic solidification, showing strip, block and irregular shapes that are mainly distributed on the grain boundaries. When the mass fractions of Ti and C are high, TiC particles precipitate in the form of eutectic solidification, showing flake and dendritic shapes that are distributed on the grain boundaries and also in the grains. There are orientation relationships between the eutectic particles and the matrix.

Effect of carbon addition on the microstructure and mechanical behavior of near equiatomic NiTi alloy wire

According to the phase diagram, 0.03 wt% (C0.03) and 0.05 wt% (C0.05) carbon were added to Ni50.2Ti49.8 alloy, and the alloy wires with a diameter of 1.2 mm were prepared by vacuum induction melting and drawing. The results show that during melting and solidification, C combines with Ti in C0.03 and C0.05 to form eutectic TiC and primary TiC, respectively. Compared with the NiTi alloy wire without C, the tensile fatigue life (22866 cycles under 700 MPa tensile stress) and tensile strength (1536 MPa) of the alloy were increased by 39 % and 22 % respectively when 0.03 wt% C was added. With the further increase of C content to 0.05 wt%, the two properties began to deteriorate. This is mainly related to the changes of matrix phase composition, second phase morphology and internal microstructure caused by the addition of different amounts of C. The research results show that on the premise of following the requirements for C content (C ≤ 0.04 wt%) in the international standard ASTM F2063-18 for medical NiTi alloy composition, adding a certain amount of C (such as 0.03 wt%) to NiTi alloy is beneficial to improving the tensile strength and tensile fatigue life of wire.

Microstructure Evolution and Enhanced Hot Workability of TiC/Ti-6Al-4V Composites Fabricated by Melt Hydrogenation.

Improving the hot workability and reducing the processing cost are critical steps to expanding the application of TiC/Ti-6Al-4V composites. This study employed melt hydrogenation to fabricate TiC/Ti-6Al-4V composites under a mixed atmosphere of hydrogen and argon. Experimental results indicated that hydrogen had an obvious influence on the growth and morphology of eutectic TiC particles, and the size of eutectic TiC and primary β grains was significantly increased. As a result, large-sized eutectic TiC was distributed along the grain boundaries of primary β grains. Hot compression results showed that the peak flowing stress of composites was reduced by hydrogen, which resulted in an improvement of hot workability, especially in the (α + β) phase region, and the best results were obtained at 900 °C/0.01 s-1, at which the peak stress decreased from 241 ± 9 to 190 ± 8 MPa (a decrease of 21.2%). Inspection of the microstructure after hot compression showed that hydrogen improved the proportion of DRX grains from ~62.7% to ~83.2%, and hydrogen also decreased the density of dislocations, which were attributed to hydrogen accelerating atomic diffusion. Enhanced hot workability resulted from hydrogen atoms decreasing the atomic bonding force of the titanium matrix, hydrogen reducing the β/(α + β) transition temperature, the higher proportion of DRX, and the higher mobility of dislocations. It is expected that the findings of this study may support the development of a simple and efficient method to reduce the processing cost of TiC/Ti-6Al-4V composites.

TiCp reinforced Ti6Al4V of follow-up synchronous electromagnetic induction-laser hybrid directed energy deposition: Microstructure evolution and mechanical properties

In this work, the follow-up synchronous electromagnetic induction-laser hybrid directed energy deposition (FEMI-DED) was proposed to prepare 10 wt% TiC p reinforced Ti6Al4V. Compared with DED, microstructure and mechanical properties of TiC p reinforced Ti6Al4V were improved by the Joule heat and Lorentz force of the electromagnetic field in FEMI-DED. Moreover, the effectiveness of surface induction heating in front and back of the molten pool was elucidated. The results show that in DED and FEMI-DED, primary TiC and eutectic TiC were both reinforced phase, and the primary TiC had the semi-coherent interface with α-Ti. In the DED, the primary TiC were coarse dendrite. The tensile strength and elongation were 893 ± 4.1 MPa and 0.70 ± 0.04 %, and the premature cracking of dendritic TiC was found by fracture analysis. But in the FEMI-DED, the quantity of refined dendritic primary TiC was decreased by ~26.2 %, and lots of granular TiC with the size of ~1.45 µm appeared. This is because the Joule heat reduced temperature gradient and increased growth rate, then the nucleation of granular TiC was promoted. Meanwhile, the Lorentz force increased dendrite fragmentation. By load-bearing strengthening of granular TiC, the tensile strength increased to 960 ± 11.5 MPa with the elongation of 0.73 ± 0.04 %.

Enhanced mechanical properties of in situ synthesized TiC/Ti composites by pulsed laser directed energy deposition

Titanium matrix composites (TMCs) have attracted extensive attention of researchers due to their excellent properties. However, the strength and ductility of TMCs hardly co-exist and show a trade-off between each other. To overcome the problem, in this study, with feeding the commerically pure titanium (CP–Ti) powder decorated by nano carbon, TiC reinforced Ti matrix composites were synthesized in situ by Pulsed Laser Directed Energy Deposition (PLDED). As the C content increases, the size, content and morphology of the TiC particles gradually change and the irregular block α phase transform to lath α phase in the matrix. As for Ti+0.6 wt% C, due to the strengthening effect of dispersed eutectic TiC and the evolution of morphology of α phase in the matrix, the ultimate tensile strength of TiC/Ti composites (940 MPa) is ∼84.3% and ∼108.9% higher than that of the PLDED and forged CP-Ti respectively, while retaining excellent elongation to failure (18.9%), which effectively solves the problem of strong-plastic contradiction existing in the preparation of TMCs. And at this carbon content, the friction and wear properties of the composites are effectively improved, the friction coefficient (0.26) is 55% lower than that of CP-Ti (0.58) obtained under the same process. This work shows a great potential way to significantly improve the mechanical properties of titanium alloys.

Preparation of Dual‐Scale TiC‐Precipitated Bainitic Wear‐Resistant Steel by Solid Solution and Forging Deformation

Preparation of Dual‐Scale TiC‐Precipitated Bainitic Wear‐Resistant Steel by Solid Solution and Forging Deformation

Investigation of the microstructure evolution of TiC/Ti-6Al-4V composite manufactured by laser melting deposition

This study investigated the microstructure evolution of the TiC/Ti-6Al-4V matrix composite produced using a 1073 nm continuous wave (CW), IPG Ytterbium fibre laser. The influence of thermal gradient, overlap, and re-melting of the previous layers on the microstructure of TiC/Ti6Al4V matrix composite samples was analyzed using the scanning electron microscope (SEM). The microstructure showed that the TiC/Ti-6Al-4V composite samples are composed of undissolved TiC, in-situ TiC (eutectic TiC and primary TiC), α Ti and β Ti. While martensite microstructure was observed on the Ti-6Al-4V alloy samples. It was observed that the single-track and single-layer composite samples are consists of blocky TiC, granular eutectic TiC, chain-shaped eutectic TiC and dendritic primary TiC phases. While the cube composite sample shows granular primary TiC and dendritic primary TiC. Dendritic primary TiC is observed in all composite samples.

Graded microstructure and properties of TiCp/Ti6Al4V composites manufactured by laser melting deposition

In this paper, 50 vol% TiCp/Ti6Al4V composites without pores, cracks or poor fusion were fabricated by laser melting deposition (LMD) technology using 500 W laser power (lower power, LP) and 1000 W laser power (higher power, HP). The microstructure of different deposited layers was analyzed and the corresponding microhardness was measured. The results show that the composites are composed of undissolved TiC, in-situ TiC (eutectic TiC and primary TiC), α Ti and β Ti. It is interesting that the microstructure from the bottom layer to the top layer presents a graded distribution when all layers have the same composition. The eutectic TiC is mainly formed in lower layers while the primary TiC is mainly in upper layers. With increasing layer number, the size and number of the primary TiC grains increase and the primary TiC grows gradually from granules into dendrites, however, the number of the undissolved TiC particles decreases along the depositing direction. The simulation results show that the peak temperature of deposited layer increases while the cooling rate decreases with increasing layer number. Different thermal history affects the diffusion of carbon and the evolution of TiC, and then affects the microstructure distribution of the composites. This graded microstructure leads to the graded distribution of microhardness. The microhardness of the LP composite rises from 432.5 HV to 488.1 HV, while the HP composite rises from 435.5 HV to 604.3 HV from the bottom layer to the top layer, respectively.

Microstructural evolution, mechanical and tribological properties of TiC/Ti6Al4V composites with unique microstructure prepared by SLM

Based on the advantage of rapidly fabricating parts with complex geometric shapes, selective laser melting (SLM), an additive manufacturing technology, is utilized to process 3 wt.% TiC/Ti6Al4V composites. A TiC-reinforced Ti6Al4V composite with directionally grown unique microstructures is prepared by SLM. The effect of the laser power and scanning speed on the relative density, constitutional phases, and microstructure features is investigated systematically. The microstructure evolution mechanism is clarified. Moreover, the influence of the unique microstructure on the mechanical and tribological properties is investigated. The results indicate that the relative density of the SLM-processed TiC/Ti6Al4V composite can reach 98.7%. Because of the special processing technology used in SLM, unique nanoscale lamellar and needle-like eutectic TiC reinforcement phases, which have never been observed in TiC/Ti6Al4V composites prepared by other flexible laser additive manufacturing technologies, are formed. Furthermore, the composites are dominated by extremely small grains. The nanoscale eutectic TiC and refined grains significantly enhance the hardness and tensile strength of the composites. The microhardness and ultimate tensile strength reach 487 HV and 1565 MPa, respectively. More importantly, the nanoscale reinforcement promotes the migration of C and the formation of a dense solid lubricant film during friction, leading to excellent tribological properties at different applied loads. As the applied load increases from 5 N to 15 N, due to the enhancement of the effect of the nanoscale reinforcement, the tribological properties of the SLM-processed TiC/Ti6Al4V composites are further improved. At an applied load of 15 N, the friction coefficient and wear rate reach 0.303 and 1.221 mm 3 /m∙N, respectively. • TiC/Ti6Al4V composites with unique nanoscale eutectic TiC reinforcement are prepared by SLM for the first time. • The microstructure formation condition and corresponding evolution mechanism under different parameters are clarified. • The SLM-processed Ti6Al4V/TiC composite shows excellent mechanical and tribological properties. • Mechanical and tribological properties reinforcement mechanism of the SLM-processed Ti6Al4V/TiC composite is established.

Effect of C addition on microstructure and mechanical properties of Nb–Si–Ti based alloys

To improve the mechanical properties of Nb–Si alloy, the influence of C addition on microstructural evolution and mechanical properties of Nb–16Si–24Ti based alloys is studied. Results show that with the C content increase, the microstructure of Nb–16Si–24Ti- x C transforms from hypoeutectic structure to nearly eutectic structure, and the phase constitutions transform from Nbss + (Nb, Ti) 3 Si to Nbss + γ-(Nb, Ti) 5 Si 3 . The microstructure transforms into fully eutectic structure and TiC phase is precipitated by addition of 4 at.% C. The element C is mainly dissolved in the Nbss phase, and the nanoindentation hardness of Nbss phase obviously increases with the increasing of C content, which is attributed to the solid solution strengthening by C addition. The fracture toughness increases from 6.3 MPa m 1/2 to 14.9 MPa m 1/2 , as the C content increases from 0 at.% to 3 at.%, since with the C content increase, the c/a ratio decreases, the Nbss phase content increases, and the Nbss phase becomes more continuous. The addition of 4 at.% C induces the formation of TiC phase in the matrix, and thus decreases the fracture toughness.

Microstructure and dry sliding wear behavior of as-cast TiCp/Ti-1100-0.5Nb titanium matrix composite at elevated temperatures

The microstructure and dry sliding wear performance of as-cast TiCp/Ti-1100-0.5Nb composite at 25 °C, 500 °C and 600 °C were systematically investigated. Results show that the solidification matrix microstructure is the typical Widmanstatten structure. The eutectic TiC particles are uniformly distributed in the matrix in the form of feathery, long rod and strip-like shapes. Meanwhile, the interface between TiC and titanium matrix is clear and without any reaction. The wear rate of TiCp/Ti-1100-0.5Nb at 600 °C and 500 °C is reduced by 95.8% and 79.9%, respectively, compared with that of the value of 51.8×10−6 mm3·mm−1 at 25 °C. The friction coefficient of the steady-state period at 25 °C, 500 °C, 600 °C is 0.48, 0.8, 1.2, respectively, and the variation extent of the friction coefficient at elevated temperatures is greater than at 25 °C. The wear mechanism is changed from the mixture of adhesive wear and abrasive wear to mild oxidation wear with rising temperature. It can also be concluded that the composite possesses excellent high temperature wear resistance. The high-wear resistance of the composite is attributed to the Fe2O3 and TiO2. The presence of Fe2O3 and TiO2 reduces the wear rate, increases the friction coefficient, and also improves the range-ability of the friction coefficient.

Coarse TiC particles reinforced H13 steel matrix composites produced by laser cladding

Coarse TiC particles (more than 50 μm) reinforced H13 steel composites produced by laser cladding with various ceramic volume fraction were investigated. The effects of the ceramic volume fraction on the microstructure and hardness of the produced TiC/H13 composite were obtained. The results indicated that preheating conbined with slowing laser beam scanning speed were relatively useful for crack suppression and formation of composites with high TiC volume fraction. The microstructure of the TiC/H13 composite consisted of various TiC particles, including coarse TiC, initial fine TiC, primary TiC, lamellar-type eutectic TiC, austenite and martensite. By increasing the concentration of TiC in the composite, the volume fraction of residual austensute and the carbon content of martensite as well as the composite hardness had a significant increase. Nanoindentation hardness results showed that the hardness of the initial TiC particle was the highest, followed by the primary TiC, among the various shaped TiC within the deposit. The highest average hardness of the TiC/H13 composite was 1365 HV, which was more than twice as much as the H13 substrate hardness.

In Situ TiC‐Reinforced Steel Matrix: Heterogeneous Nucleation and Formation Mechanism of Divorced Eutectic TiC

Divorced eutectic TiC (TiCE) influences the mechanical properties of TiC‐reinforced wear‐resistant steels. However, there is a lack of information with respect to the heterogeneous nucleation, growth, and formation mechanism of divorced TiCE. To this end, the morphology, orientation, and origin of the divorced TiCE in TiC‐reinforced wear‐resistant steel are thoroughly examined. Combined with the calculated planar disregistry between primary TiC (TiCP) and divorced TiCE and their actual orientation relationship examined using the electron backscatter diffraction (EBSD) technique, it is indicated that TiCP serves as the preferred heterogeneous site for divorced TiCE during solidification. The precipitation mechanism for the divorced TiCE on the TiCP is put forward and accounts for why the direction of [100] is the preferential growth direction.

Evolution of microstructures and divorced eutectic TiC formed during solidification of the wear-resistant steel

The effect of cooling rate on the microstructure and TiC precipitation of TiC-reinforced wear-resistant steel was investigated by different casting techniques. Thermodynamic and solute segregation modeling was performed to determine the evolution of TiC fraction in wear-resistant steel after rapid solidification. The evolution of TiC fraction due to solute segregation within the framework of Clyne–Kurz (C-K) model was examined. The model prediction is consistent with the experimental results.

Effect of TiC particle size on the microstructure and tensile properties of TiCp/Ti6Al4V composites fabricated by laser melting deposition

TiC particle (TiCp) reinforced Ti6Al4V (TiCp/Ti6Al4V) titanium matrix composites with coated powders (TiC: <10 μm) and small-sized (TiC: 25–45 μm), medium-sized (TiC: 45–75 μm) and large-sized (TiC: 75–100 μm) mixed powders were produced by laser melting deposition (LMD). The influence of TiC particle size on the microstructure and tensile properties of composites was researched. The granular and chain shaped eutectic in-situ TiC phases distributed homogeneously in the composites with coated powders. Besides the eutectic TiC phases, the unmelted TiC particles existed in composites with mixed powders. The number of granular eutectic TiC phases reduced when the TiC particles size increased. The formation mechanism of the microstructure of composites was discussed in depth. The tensile properties of composites with small-sized and medium-sized mixed powders were similar, which were better than those of composites with large-sized mixed powders but were worse than those of composites with coated powders. Compared with that of composites with large-sized mixed powders, the tensile strength (1231.3 MPa) and elongation (2.12%) of composites with coated powders were improved by nearly 4.6% and 259.3%, respectively. This was attributed to the existence of more granular eutectic TiC phases that were difficult to crack, the homogeneous distribution of eutectic TiC phases and the strong bonding of the interfaces between eutectic TiC phases and matrix. The premature damage of the larger unmelted TiC particles during the LMD process or at the initial stage of plastic deformation and the decohesion of the interface between larger TiC particle and matrix deteriorated the tensile properties of the composites fabricated with large-sized mixed powders. The fracture mechanism of composites with coated powders was controlled by eutectic TiC phases cracking followed by ductile damage of matrix. However, the fracture mechanism of composites with mixed powders was controlled by unmelted TiC particles cracking followed by eutectic TiC phases cracking and then by ductile damage of matrix.

Microstructure and tensile properties of TiCp/Ti6Al4V titanium matrix composites manufactured by laser melting deposition

Laser melting deposition (LMD) technique was used to manufacture TiC particle (TiCp) reinforced Ti6Al4V (TiCp/Ti6Al4V) titanium matrix composites with TiC volume fraction ranging from 5% to 30%. The microstructure and tensile properties of as-deposited and heat-treated TiCp/Ti6Al4V composites were studied. Microstructure and tensile properties of TiCp/Ti6Al4V varied as the TiC volume fraction changing. The (i) microstructural evolution of TiCp/Ti6Al4V under different TiC volume fraction and (ii) the effect of heat treatment on modifying microstructure and properties of the composites were researched. Moreover, the strengthening mechanism and fracture mechanism of the composites were discussed. The results showed that composites were composed of α Ti, β Ti, and TiC. The undissolved TiC particles were observed in all the composites. The strip-like eutectic TiC phases were observed in the composites when the volume fraction of TiC was 5%, while many dendritic primary TiC phases existed in the composites when the volume fraction of TiC exceeded 10%. When the heat treatment was held at 950°C for 10h, the basketweave microstructure and partly dissolved off strip-like eutectic TiC phases existed in the composites with 5 vol.% TiC. The strength of the TiCp/Ti6Al4V with 5% TiC volume fraction was improved by nearly 12.3% compared with that of the Ti6Al4V matrix alloys. Compared with that of the as-deposited composites, the ultimate tensile strength of TiCp/Ti6Al4V composites heat-treated at 950°C decreased only from 1225.5MPa to 1202.2MPa. However, the elongation of heat-treated composites increased from 1.31% to 3.95%, which was attributed to the presence of both basketweave microstructure and dissolved off strip-like eutectic TiC. The fracture mechanism of TiCp/Ti6Al4V composites was quasi-cleavage fracture.

Microstructure and mechanical properties of functionally graded TiCp/Ti6Al4V composite fabricated by laser melting deposition

Crack-free functionally graded TiC particle (TiCp) reinforced Ti6Al4V (TiCp/Ti6Al4V) composite was manufactured by laser melting deposition (LMD) technology with TiC volume fraction changing gradually from 0% to 50%. This research focuses on the relationship between the microstructure and mechanical properties (microhardness and tensile properties) of TiCp/Ti6Al4V composites under different TiC volume fractions. Besides the unmelted TiC particles, the granular and chain shaped eutectic TiC phases are observed in the composite with 5vol% TiC due to the melting and dissolution of TiC particles into matrix. The granular and dendritic primary TiC phases are obtained in the composite with 10vol% TiC, while the chain shaped eutectic TiC phases can scarcely be seen. The main reinforcement phases are primary TiC phases when the TiC volume fraction exceeds 15%. (i) The quantity of unmelted TiC particles, (ii) the quantity and size of primary TiC phases and (iii) the porosity of composite increase gradually when the TiC volume fraction increases. The interfaces exhibit good bonding between consecutive layers. The microhardness of the functionally graded TiCp/Ti6Al4V composite increases gradually with TiC volume fraction increasing. It is attributed to the C element in solid solution and the appearance of eutectic and primary TiC phases. The microhardness at the top layer with 50vol% TiC is improved by nearly 94% compared with that at the Ti6Al4V side. The tensile strength of TiCp/Ti6Al4V composite with 5vol% TiC is enhanced by nearly 12.3% compared with that of the Ti6Al4V matrix alloy. However, both the tensile strength and elongation of composite decrease gradually when the TiC volume fraction exceeds 5%. The reason is that the quantity of brittle unmelted TiC particles and the quantity and size of dendritic TiC phases increase with TiC volume fraction increasing. The fracture mechanism of the TiCp/Ti6Al4V composite is quasi-cleavage fracture.