In situ TiBX/TiXNiY/TiC reinforced Ni60 composites by laser cladding and its effect on the tribological properties

Ni-based composite coatings reinforced by TiB_X/Ti_XNi_Y/TiC with different Ti6Al4V contents were precipitated on a 35CrMoV substrate via laser cladding. The phase composition, elemental distribution, and precipitated phases of the coatings were characterised using X-ray diffraction, energy dispersive X-ray spectroscopy, scanning electron microscopy, and transmission electron microscopy. The mechanical and tribological properties of the cladding layer were also characterised. The results showed that the coating contained TiB₂, TiC, TiB, Ni₃Ti, and NiTi₂ phases with uniform elemental distribution and grain refinement. A schematic of the growth model and precipitation sequence of the reinforced phases was generated. The microstructure, elemental segregation, hardness, and friction behaviour of the cladding layer were significantly influenced by the addition of Ti6Al4V. The optimal microstructure and best mechanical properties were obtained by the addition of 4 wt% Ti6Al4V, with that coating possessing a hardness, average friction coefficient, and wear volume of 770.8 HV₁, 0.180 and 6132 um³, respectively.     

Influence of α-Si3N4 coarse powder on densification,microstructure, mechanical properties,and thermal behavior of silicon nitride ceramics

Silicon nitride (Si₃N₄) ceramics, with different ratios of fine and coarse α-Si₃N₄ powders, were prepared by spark plasma sintering (SPS) and heat treatment. Further, the influence of coarse α-Si₃N₄ powder on densification, microstructure, mechanical properties, and thermal behavior of Si₃N₄ ceramics was systematically investigated. Compared with fine particles, coarse particles exhibit a slower phase transition rate and remain intact until the end of SPS. The remaining large-sized grains of coarse α-Si₃N₄ induce extensive growth of neighboring β-Si₃N₄ grains and promote the development of large elongated grains. Noteworthy, an appropriate number of large elongated grains distributed among fine-grained matrix forms bimodal microstructural distribution, which is conducive to superior flexural strength. Herein, Si₃N₄ ceramics with flexural strength of 861.34 MPa and thermal conductivity of 65.76 W m⁻¹ K⁻¹ were obtained after the addition of 40 wt% coarse α-Si₃N₄ powder.     

Improving the properties of remanufactured wear parts of shield tunneling machines by novel Fe-based composite coatings

With the aim of remanufacturing high-value wear parts of shield tunneling machines, novel Fe-based composite coatings were prepared by collaborative modification with nano-TiC and nano-CeO₂ particles. This work aims to improve the wear properties of Fe-based alloy coatings by regulating the morphology and dispersion of TiC through the addition of different contents of nano-TiC and nano-CeO₂. First, the coatings with different contents of nano-TiC (from 5 wt% to 15 wt%) and nano-CeO₂ (from 1 wt% to 2 wt%) were prepared by laser cladding. Subsequently, the microstructure, phase composition, microhardness, and wear properties of the coatings were examined. Furthermore, the wear morphology and the influence mechanism of nano-particles on the wear resistance of the coatings were investigated. It was found that the addition of nano-TiC eliminates the macro-defects of Fe55 alloy coating. Meanwhile, the morphology and dispersion of TiC particles in coatings were affected by the content of nano-TiC and nano-CeO₂. Specifically, the addition of 1 wt% nano-CeO₂ facilitates to the formation of near-spherical tiny TiC particles with low agglomeration in the coating. Therefore, the Fe55 + 10 wt% nano-TiC+1 wt% nano-CeO₂ coating exhibits the best wear property among all the prepared Fe-based coatings. This paper provides theoretical guidance for the preparation of the modified Fe-based coating with excellent wear resistance.     

Preparation and investigation of pulse co-deposited duplex nanoparticles reinforced Ni-Mo coatings under different electrodeposition parameters

In this work, Ni–Mo–SiC–TiN nanocomposite coatings were deposited on aluminium alloy by pulse electrodeposition with various electrodeposition parameters. The influences of the pulse frequency and duty cycle on the phase structure, morphology, mechanical and corrosion performance of the coatings were systematically investigated. The results showed that with increasing pulse frequency and decreasing duty cycle, the content of embedded duplex nanoparticles increased, and the grains refined gradually. The nanocomposite coating that was prepared at 20% duty cycle and 1000 Hz pulse frequency exhibited compact, uniform, and fine microstructures with the maximum incorporation of nanoparticles (6.81 wt% TiN and 1.72 wt% SiC). The wear rate and average friction coefficient then declined to 4.812 × 10^?4 mm³/N·m and 0.13, respectively, with a maximum microhardness of 519 HV. Simultaneously, the corrosion current density was reduced to 3.11 μA/cm², and a maximum impedance of 34888 Ω cm² was exhibited. The uniformly distributed duplex nanoparticles acted as a hindrance, which consequently supported the enhancement of corrosion and wear resistance. By investigating the variation of the pulse diffusion layer with electrical parameters, it was discovered that when the crystallite size is equivalent to or smaller than the diffusion layer thickness, it would be easier to cross the diffusion layer to incorporate in the coating. Additionally, the effects of various duty cycles and pulse frequencies on the nucleation process of the grains were discussed.     

Microstructure and mechanical properties of plasma sprayed TiC/Ti5Si3/Ti3SiC2 composite coatings with Al additions

The mass production of MAX phase coatings such as Ti₃SiC₂ and Ti₃AlC₂ using the plasma spraying method is highly challenging due to its ultra-high temperature and short reaction time. In this study, agglomerate powders of 3Ti/SiC/C/xAl with various Al contents (x = 0–1.5) were prepared to form TiC/Ti₅Si₃/Ti₃SiC₂ composite coatings using the plasma spraying technique. The effect of the Al addition on the microstructures and mechanical performances of the as-sprayed coatings was investigated. The addition of Al decreased the TiC content of the coatings while increasing their Ti₃SiC₂ content significantly. The addition of even small amounts of Al improved the MAX phase fraction of the coatings from 8.95 wt% (x = 0) to 34.05 wt% (x = 0.2) and 41.60 wt% (x = 0.5). Excess Al did not affect the Ti₃SiC₂ content of the coatings. The composite coatings showed a lamellar structure with pores and microcracks. With the addition of Al, the microhardness of the coatings increased slightly, while the fracture toughness improved significantly. The composite coatings with Al showed better wear resistance than those without Al. The wear mechanism of the coatings was a combination of adhesive wear, abrasive wear, and oxidative wear.     

Microstructures and mechanical properties of TiB2 composite ceramics with co-addition of Ti and TiC fabricated by SPS

TiB₂ composite ceramics containing different amounts of Ti and TiC were fabricated via spark plasma sintering (SPS), and effects of their addition contents on the microstructure and mechanical properties were discussed. The newly formed phases of TiB with a cubic lattice structure in the composite ceramics were observed. At a relatively low temperature of 1510 °C, pressure of 50 MPa, and holding time of 5 min, the TiB₂ composite ceramic with 30 wt% TiC and 10 wt% Ti additions acquired an excellent strength of 727 MPa and a high toughness of 7.62 MPa m^1/2. The improvement in strength and toughness was attributed to the mixed fracture mode, second phase strengthening, and increased energy consumption for crack propagation caused by the newly formed phases and fine TiC particles. In addition, the significant effects of the Ti and TiC addition contents on the densification temperature and mechanical properties of the composite ceramics were determined using analysis of variance (ANOVA).     

Effect of Si content on the microstructure and properties of Ti–Si–C composite coatings prepared by reactive plasma spraying

In this study, Ti–Si–C composite coatings were synthesized via plasma spraying of agglomerated powders prepared by a spray drying/precursor pyrolysis technology using Ti, Si, and sucrose powders. The influence of Si content, ranging from 0 wt% to 24 wt%, on the microstructure, mechanical properties, and oxidation resistance of the composite coatings was investigated. Results show that the phase composition of the Ti–Si–C composite coatings changes with the increasing Si content. The coatings without Si addition consist of TiC and Ti₃O; the coatings with 6–18 wt% Si are composed of TiC, Ti₅Si₃, and Ti₃O; the coatings with Si content of 24 wt% form only TiC and Ti₅Si₃ phases. As the Si content increases, the hardness of the Ti–Si–C composite coatings increases first and then decreases, depending on the intrinsic hardness of the ceramic phases, the brittleness of Ti₅Si₃, and the defects such as pores and cracks. The Ti–Si–C composite coatings have high wear resistance due to the in-situ synthesized high-hardness TiC and Ti₅Si₃. Owing to the high brittleness of Ti₅Si₃, the increasing Si content leads to higher wear volume loss at room temperature, which can be partially improved in high-temperature wear tests. The oxidation resistance of Ti–Si–C composite coatings increases with the increase of Si content, and the higher the oxidation temperature, the more obvious the influence of the Si addition on oxidation resistance.     

Effect of TiN content on properties of NiFe2O4-based ceramic inert anode for aluminum electrolysis

NiFe₂O₄-based ceramic inert anodes for aluminum electrolysis doped with various TiN nanoparticles were prepared by a two-step cold-pressing sintering process to investigate how TiN affected the sintering behavior and properties of the composites. The differential scanning calorimetry-thermogravimetry (DSC-TG), X-ray diffraction (XRD), and microstructure analysis results indicated that the Ti and N were evenly distributed in the NiFe₂O₄ matrix to form a solid solution. The maximum linear shrinkage and linear shrinkage rate were enhanced with the increase of TiN nanoparticles contents, and the sintering activation energy of initial stage was lowered from 382.63 to 279.58 kJ mol⁻¹ with the TiN nanoparticles additive range from 0 to 9 wt%. When the content of TiN nanoparticles was 7 wt%, the relative density, bending strength, and elastic modulus reached their maximum values of 97.24%, 73.88 MPa, and 3.77 GPa, respectively, whereas the minimum static corrosion rate of NiFe₂O₄-based ceramic of 0.00114 g cm⁻² h⁻¹ was obtained, mainly attributed to the relatively dense and stable microstructure. The electrical conductivity of NiFe₂O₄-based ceramics presented a clear ascending trend with increasing TiN nanoparticles content and elevated temperature, attributed to the increased concentration and migration rate of carrier.     

Tribological behavior of composites fabricated by reactive SPS sintering in Ti-Si-C system

In this study, wear and friction behavior of two based-composites from the Ti-Si-C system, (40 wt% TiC; 28 wt% Ti₅Si₃; 17 wt% Ti₃SiC₂) and (18 wt% TiC; 26 wt% Ti₅Si₃; 41 wt% Ti₃SiC₂) reinforced by 15 wt% of large size SiC (100-150 µm) particles were investigated. The four-phase composites exhibited approximatively the same friction coefficient (µ ~ 0.9) under high loads (10 N and 7 N). The composite with high Ti₃SiC₂ showed higher wear rate values by one order of magnitude. However, under 1 N, the composite with high TiC content showed a higher running-in period and a lower steady state µ value (0.37 after 1000 m sliding distance). Scanning electron microscopy, Energy Dispersive X-Ray and Raman spectroscopy analysis of the worn surfaces of the two composites revealed that oxidation was the dominant wear mechanism. The oxidation process and the removal kinetics of the oxides during sliding controlled the tribological behavior of the composites. The influence of processing variables on microstructures development and wear mechanisms of the composites is discussed.     

Feasibility study of adding buffer layers for the laser deposition of high-ceramic content (TiB + TiC)–Ti coatings using B4C/Ti powders

Wear-resistant coatings have been widely used to improve the tribological properties of titanium-based parts, structures, and tools, such as engine blades, tanker trucks, heat exchangers, and drilling bits, in the aerospace industries, chemical industries, offshore engineering, and oil and gas engineering. In the view of the applications in the fabrication of wear-resistant coatings on titanium substrates, the laser deposition of ceramic reinforced titanium coatings is widely investigated. Reported investigations show that the (TiB + TiC) reinforced titanium matrix composite coatings with high ceramic content can significantly increase the hardness and wear resistance. However, due to the low compatibility between ceramics and titanium, a high ceramic content always leads to a relatively low bonding quality and the generation of cracks and defects. To fabricate the high ceramic content (TiB + TiC)–Ti coatings, this study investigates the feasibility of adding buffer layers for the first time. The phase compositions, microstructures, element compositions, and mechanical properties of the different layers have been analyzed by XRD, SEM, EDS, and instruments to measure hardness and wear resistance. The deposited gradient coatings are free of fabrication defects with good metallic adhesion with titanium substrates. In the center of the top coating layers, the extremely high-volume content of ceramic reinforcements (including the major component of TiB and TiC and the minor component of TiB₂, B₂₅C, and unreacted B₄C) leads to high microhardness and excellent wear resistance. These results suggest that adding buffer layers is a feasible method to fabricate high-ceramic content coatings on titanium-based structures and tools.     

Influence of Y2O3 on the microstructure and tribological properties of Ti-based wear-resistant laser-clad layers on TC4 alloy

Multi-track Ti-based wear-resistant composite coatings were fabricated on TC4 alloy surfaces using laser-clad TC4 + Ni45 + Co–WC mixed powders with different Y₂O₃ contents (0, 1, and 3 wt%). The microstructure, microhardness, and tribological properties of the coatings were characterised using X-ray diffraction, scanning electron microscopy, energy dispersive spectrometry, electron probe X-ray micro analyser, microhardness tester, and friction and wear testing apparatus. The results showed that the number of cracks on the coating surfaces gradually decreased with the addition of Y₂O₃ and that residual Co–WC powders existed in the coating subsurfaces. The phase composition of the coatings with different Y₂O₃ contents remained unchanged and was mainly composed of reinforcing phases of TiC, TiB₂, Ti₂Ni, and matrix α-Ti. With the addition of Y₂O₃, the coating microstructure was remarkably refined, the direction characteristic of the TiC dendrites obviously weakened, and the nucleation rate significantly increased. When the added Y₂O₃ was 3 wt%, a large amount of TiB₂–TiC-dependent growth composite phases precipitated in the coating. The two-dimensional lattice misfit between (0001)_TiB2 and (111)_TiC was 0.912%, which indicated that TiB₂ and TiC formed a coherent interface. When the amount of Y₂O₃ was increased, the microhardness of the coatings gradually decreased, and the wear volume of the coatings first increased and then decreased. Under the effect of the TiB₂–TiC composite phases, the wear resistance of the 3 wt% Y₂O₃ coating was optimal. The 3 wt% Y₂O₃ coating friction coefficient was the lowest, and the wear mechanism was abrasive wear.     

Characterisation of in-situ reactive plasma-sprayed nano-(Ti,V)N composite ceramic coatings with various V concentrations

The effect of V concentration on the microstructure and phase composition of nano-(Ti, V)N composite ceramic coatings prepared by in-situ reactive plasma spraying of mechanically mixed Ti–V powders were investigated using X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, X-ray energy dispersive spectroscopy, and transmission electron microscopy. The microhardness, toughness, wear resistance, and strengthening mechanism of the prepared nano-(Ti, V)N coatings were measured and analysed. The results showed that the nano-(Ti, V)N coating comprised a large proportion of nano-(Ti, V)N grains, which was the solid solution of TiN and VN. All the V atoms completely entered the TiN lattice and the solubility limit of V in TiN is approximately 25 wt%. The grains of the (Ti, V)N (25 wt% V) coating had a face-centred cubic structure and a large quantity of twins; they were primarily equiaxed grains morphology with a few columnar grains. From comparing the experimental statistics, the (Ti, V)N (25 wt% V) coating displayed the highest microhardness (1952 ± 78.5 Hv) and the most even dispersion but a slightly lower toughness compared with the (Ti, V)N (35 wt% V) coating. The (Ti, V)N (25 wt% V) coating with a dense microstructure obtained a high microhardness due to dislocation strengthening, fine grain strengthening, and solid solution strengthening (from the solid solution of VN in TiN). Furthermore, a lower friction coefficient and wear volume loss indicated that the (Ti, V)N (25 wt% V) coating had superior tribological properties and great potential as a wear resistant coating.     

Tribological behavior studies of chemically bonded phosphate ceramic coatings reinforced with modified multi-walled carbon nanotubes (MWCNTs)

To improve the wear resistance of the chemically bonded phosphate ceramic coatings, MWCNTs are selected as the reinforcement after the modification. The high temperature wear experiment is carried out to investigate the wear behavior of the coatings with different temperatures. The results suggest that, when the temperature is below 500℃, MWCNTs can decrease friction coefficient, and the lowest friction coefficient is about 0.28, but MWCNTs lose the lubricant function at 500℃ and the friction coefficient keeps at the level of ~ 0.68. In addition, the wear resistance of coatings is improved with the introduction of MWCNTs at 100℃ and 300℃ (the wear rate is below 15X10^-3mm³/Nm), but keeps similar level at 500℃ (the wear rate is ~ 22 × 10⁻³mm³/Nm). Besides, the wear mechanism of the coatings reinforced by MWCNTs is also investigated based on the wear behavior and microstructural characterizations. MWCNTs improve the fracture toughness by preventing the crack generation and forming the bridge when crack occurs, which leads to smooth wear tracks and good wear resistance of coatings. The coatings with MWCNTs achieve poor wear resistance at 500℃ because MWCNTs lose their strength and resistance to fatigue by oxidizing.     

Wear behavior of Fe3Al-TiN-TiB2 HVOF coatings: A comparative study between in situ and ex situ powder processing routes

In the present study, the tribological properties of High Velocity Oxy-Fuel (HVOF) coatings prepared from Fe₃Al-based composite powders were investigated. The iron aluminide matrix of the composite powders was reinforced with TiN and TiB₂ particles made using two different processing routes: a) an in situ method where fine ceramic particles were formed in the matrix by the reaction between Ti and BN, and b) an ex situ method where preformed coarse TiN and TiB₂ particles were added to the matrix. The tribomechanical performance of the coatings was assessed using indentations and pin-on-disc wear tests. Compared to ex situ samples, the Fe₃Al-based coatings strengthened with in situ ceramic particles exhibit higher microhardness and wear resistance regardless of the sliding velocity. The presence of voids, cracks and scratches/grooves in the wear track of the in situ coatings and the coating material transferred to the corresponding counterpart suggest that coatings with fine reinforcing particles fail predominantly via delamination and adhesive wear mechanisms. In the case of the ex situ coatings, the presence of a significant amount of hard ceramic particles within the wear track indicates that abrasive wear plays a dominant role in the degradation mechanism. Oxidation wear also contributed to material removal at high sliding velocity since transfer materials inside the wear track contain a high oxygen content compared to the unworn region regardless of the coating type.     

Effect of TiC addition on the microstructure and properties of Ni3Ta–TaC reinforced Ni-based wear-resistant coating

The present study focuses on the surface wear-resistant strengthening technology of the tunnel boring machine disc cutter ring. Ni₃Ta–TaC reinforced Ni-based wear-resistant coatings were synthesized in-situ on the surface of 5Cr5MoSiV steel by laser cladding with pure Ni spherical powder, pure Ta spherical powder and Ni coated graphite. To inhibit coating cracking, TiC powder was added to promote the in-situ formation of TaC. The effect of adding TiC on the microstructure and properties of Ni-based wear-resistant coating has been investigated by experiments and first-principles calculation. The results show that Ni₃Ta and TaC particles are synthesized in-situ in the coating, and small TaC particles are aggregated around TiC. The orientation relationship of TaC (100)//TiC (100) is confirmed by EBSD and TEM. The properties of interface of TaC (100) and TiC (100) are calculated by the first-principles, showing that the C–Ti and Ta–C interface has high adhesion and good stability. The wear resistance of the two coatings is 4 times higher than that of the substrate. The addition of TiC can effectively inhibit the formation of the lath-shaped Ni₃Ta intermetallic compound and cracks, resulting in excellent wear resistance and toughness.     

Microstructure and properties of Ni-WC gradient composite coating prepared by laser cladding

In this study, an Ni-based gradient composite coating reinforced with WC was prepared on a Q345R steel substrate by laser cladding. The Ni-WC composite coating was designed as a multilayer structure with gradient composition. The coating started with a layer of C276 alloy with 10 wt% WC on the substrate, and the subsequent layers were composed of Ni60 alloy with different WC contents (10, 30, and 50 wt% WC). The overall morphology, phase composition, and microstructure of the coatings were investigated. The microhardness and the wear properties of each layer of the coatings were also evaluated. The results showed that the gradient composition design was beneficial for reducing the cracking tendency. The coating was composed of an Ni-based matrix, WC, and multiple carbides and borides hard phases. With increasing WC content in the layers, the hard phases exhibited regional distribution characteristics. The WC reinforcement particles underwent different types of dissolution during the cladding process. From the surface to the substrate, the average microhardness of the coating was 1053.5 HV_0.2, 963.4 HV_0.2, 859.0 HV_0.2, 441.7 HV_0.2, and 260.5 HV_0.2. The wear tests revealed that the coefficient of friction and the wear loss values of the four layers were all lower than those of the substrate, demonstrating enhanced wear resistance.     

Optimization of microstructure and properties of composite coatings by laser cladding on titanium alloy

Recently, the current technological progress in developing laser cladding technology has brought new approaches in surface modification of titanium alloys. Herein, composite coatings were fabricated by the laser cladding process on Ti811 alloys using a coaxial powder feeding method. A comprehensive study was performed on the laser energy density (L_ed) and CeO₂ content on the structure distribution, microhardness and tribological properties of the coatings. In addition, the growth mechanism of the TiC–TiB₂ structure was studied based on the Bramfitt two-dimensional lattice mismatch theory. The results indicated that the phase composition of the coating mainly contained TiC, TiB₂, Ti₂Ni, and α-Ti. The optimized coating contributed to uniform microstructure distribution and fine grain size when L_ed was 45 J/mm² and the CeO₂ content was 2 wt%, playing an important role in the best forming quality and properties. Besides, the high matching degree of an interface between TiC (111) and TiB₂ (0001) contributed to the TiC–TiB₂ composite structure, which positively influenced the grain size and distribution of TiC. The microhardness and wear resistance of the 2Ce coating was dramatically enhanced due to the fine grain strengthening and dispersion strengthening effects of CeO₂, contributing directly to generate a high average hardness of 811.67 HV_0.5 with a lower friction coefficient.     

Pressureless sintering of SiC ceramics with improved specific stiffness

The effects of B₄C content on the specific stiffness and mechanical and thermal properties of pressureless-sintered SiC ceramics were investigated. SiC ceramics containing 2.5 wt% C and 0.7–20 wt% B₄C as sintering aids could be sintered to ≥ 99.4% of the theoretical density at 2150 °C for 1 h in Ar. The specific stiffness of SiC ceramics increased from 136.1 × 10⁶ to 144.4 × 10⁶ m²‧s⁻² when the B₄C content was increased from 0.7 to 20 wt%. The flexural strength and fracture toughness of the SiC ceramics were maximal with the incorporation of 10 wt% B₄C (558 MPa and 3.69 MPa‧m^1/2, respectively), while the thermal conductivity decreased from ∼154 to ∼83 W‧m⁻¹‧K⁻¹ when the B₄C content was increased from 0.7 to 30 wt%. The flexural strength and thermal conductivity of the developed SiC ceramic containing 20 wt% B₄C were ∼346 MPa and ∼105 W‧m⁻¹‧K⁻¹, respectively.     

Microstructural,mechanical and marine water tribological properties of plasma-sprayed graphene nanoplatelets reinforced Al2O3- 40 wt% TiO2 coating

Graphene nanoplatelets (GNPs) as reinforcement in the ceramic matrix is rising continuously due to their outstanding mechanical and lubricative properties. Herein, different compositions of GNPs (0.5–2 wt%) reinforced alumina-titania coatings were prepared using atmospheric plasma spraying. The relative density of AT coating increased from 83% to 94% with just (1.5 wt%) addition of GNP. Consequently, mechanical properties i.e. hardness and elastic modulus were improved by ~77% and ~69% respectively. Fracture toughness also increased from 2.65 ± 0.95 MPa.m^1/2 to 5.85 ± 1.07 MPa.m^1/2. Furthermore, the seawater wear test, using a ball-on-disc tribometer revealed that the wear rate of AT coating decreased from ~11 × 10^?14 m³/Nm to ~4 × 10^?14 m³/Nm, whereas the coefficient of friction reduced from 0.33 ± 0.05–0.16 ± 0.03. The mechanisms involved to improve these properties, viz. GNP sandwiching, crack bridging, crack arrest, etc. GNP’s multi-layers facilitated long-term lubricity and enhanced the wear resistance properties of the coatings.     

Erosion Behavior of Gelcast Fused Silica Ceramic Composites

In this paper, the characteristics of solid particle erosion on fused silica ceramics are investigated. Gelcasting, a near net shape forming process, is adopted for the fabrication of ceramics. Three types of ceramics with a combination of pure fused silica, fused silica+5 wt% silicon nitride (Si₃N₄)?+?1 wt% boron nitride (BN) and fused silica+5 wt% silicon nitride (Si₃N₄) +1 wt% alumina (Al₂O₃) are prepared at a constant 52 vol% solid loading, 10 wt% monomer content and 10:1 monomer ratio. Different impingement angles (30^o, 45^o, 60^o and 90^o) and three impact velocities (86 m/s, 101 m/s and 148 m/s) were chosen to examine the behavior of erosion on gelcasted ceramics using SiO₂ particles as erodent. The maximum rate of erosion is obtained at normal impingement angle (90^o), which shows the brittle nature of ceramics. The impact velocity and angle of impingement have an appreciable effect on erosion rate. Resistance to erosive wear is found to have improved with the inclusion of reinforcements in the fused silica ceramics. The erosion rates of different ceramics are compared. Ceramic composite with a combination fused silica+5 wt% Si₃N₄+ 1 wt% BN shows the highest resistance to wear. The surface roughness and morphology of the eroded surfaces have also been studied.