Zirconia Toughened Alumina Particles Research Articles

Study on casting simulation and wear properties of honeycomb configuration ZTAp-Fe composite

The primary objective of this research is to develop a honeycomb configuration ZTAp-Fe composite, with varying concentrations of ZTAp (zirconia-toughened alumina particles) at 5 wt%, 10 wt%, and 15 wt%, to address wear-related issues in mining machinery components. A numerical simulation of the casting process to study the temperature field variation in composites and gravity casting was subsequently performed using 30SiMn steel liquid. A comprehensive examination of the composite's characteristics was conducted, employing XRD, SEM, EDS, three-body abrasive wear, and scratch testing. The study revealed a metallurgical bonding between the interface of 30SiMn steel and the iron matrix, characterized by a fusion zone with a width of approximately 182 μm. Furthermore, the honeycomb configuration of the preform was found to enhance heat transfer during the casting process. Both 30SiMn steel and the iron matrix exhibited a room temperature organization of α-Fe, and the micron granular precipitates in the iron matrix are (Fe, Cr)7C3. However, it was observed that when the ZTAp content reached 15 wt%, particle accumulation hindered heat transfer, which led to pore defects, resulting in poor mechanical bonding between ZTAp and the iron matrix. Compared to various three-body abrasive wear loads (50 N, 90 N, and 130 N), the wear properties initially improved with an increase in ZTAp content from 5 wt% to 15 wt% but then weakened. The presence of hard-phase ZTAp was found to play a significant role in blocking scratches, and composites with 10 wt% ZTAp content exhibited excellent wear properties.

Interface characteristics and wear resistance of Ni-B4C plated ZTA reinforced high chromium cast iron composite

A chemical composite plating of Ni-B4C was used to prepare the surface-modified zirconia toughened alumina (ZTA) ceramic particles. The ceramic preforms were prepared by the plated ZTA and sodium silicate solution binder, followed by casting infiltration to prepare the ZTA particles reinforced high chromium cast iron (HCCI) composites. The result reveals that a distinct interface layer forms at the ZTA/HCCI interface, which consists of phases of ZrB2, FeB, Fe2B, and NaSiO4. The interfacial wettability between ZTA and HCCI is improved by the diffusion and reaction of Ni and B4C. The wear test reveals that the Ni-B4C plated ZTA particles can effectively improve the wear resistance of the ZTA/HCCI composite, and the wear rate of the composite is decreased to 11.6% of HCCI.

Microstructure and mechanical properties of Cu–Fe-ZTA cermets prepared by vacuum hot pressing sintering

Cermets with Cu and Fe as matrix and zirconia toughened alumina (ZTA) as reinforcement phase were prepared by vacuum hot pressing sintering. Electroless Ni plating was carried out on ZTA particles to improve the interfacial bonding ability between ZTA and metal matrix. Cu-xFe-ZTA cermets (x = 20, 50, 80) were prepared by using different proportions of Cu powders and Fe powders as the binder in order to investigate the influence of binder types on the grinding performance of cermets. The phase composition, microstructure, mechanical properties and grinding properties of Cu–Fe-ZTA cermets were systematically studied. It revealed that the difference of cermet grinding performance lay in the bonding force between metal matrix and abrasive. The coating ability of abrasive is stronger with the increase of Cu content in the matrix. Because the matrix is soft and easy to grind, the cermet grinding wheel material has strong self-sharpening, and Cu–20Fe-ZTA grinding effect is the best. The friction coefficient of Cu–20Fe-ZTA cermets was 0.405, the grinding surface roughness was 7.972 μm, and the residual stress σx and σy were 180.5 and 89.6 MPa, respectively. As the Fe content decreased, the grinding mechanism changed from ploughing and cutting to friction.

Investigation on mechanical properties of ZTA+ Cr3C2 + Ni reinforced EN31 steel-based composite material: Micromechanical finite-element analysis

The present investigation deals with the development of EN31 steel-based metal matrix composite material under the ultrasonic vibration effect by providing 20 kHz frequency. In the process of the development of composite material, primary and secondary reinforcement has been taken as zirconia toughened alumina (ZTA) and Cr3C2 (chromium (II) carbide), respectively. The Ni has also been taken as dissolving reinforcement material and its weight percentage (wt.%) is kept constant at 2.5%. The variation in ZTA weight percentage was selected between 1.25% and 10%. Furthermore, the weight percentage of Cr3C2 has been kept constant (2.5 wt.%) throughout the development of different composite samples. The microstructural investigation indicated the fair distribution of reinforcement particles up to the 3.75 wt.% of ZTA, developed with the ultrasonic vibration effect. Furthermore, the addition of 2.5 wt.% of nickel in the EN31 steel has improved the wettability of ZTA and Cr3C2 particles. The best values of hardness (254.22 BHN) and tensile strength (892.15 MPa) were achieved with the composition of EN31/3.75 wt.% ZTA/2.5 wt.% Cr3C2/2.5 wt.% Ni composite material sample. Furthermore, the tensile strength and hardness of EN31 steel matrix material were improved by about 45.065% and 100.36% respectively. The addition of ZTA and Cr3C2 decreases the ductility of EN31 steel matrix material. The addition of 2.5wt.% Ni powder with ZTA+ Cr3C2 improved the ductility of EN31 steel. The results revealed that the mechanical properties (tensile strength, hardness, and ductility) of the developed composite material were further improved after performing the heat treatment process. Furthermore, an approach has been made to investigate the micro-mechanical deformation of EN31/3.75 wt.% ZTA/2.5 wt.% Cr3C2 metal matrix composite representative volume element (size: 225 × 225 × 225 nm) with finite-element analysis (FEA). The maximum stress (895.60 MPa) is generated at matrix–particle interfaces, which is the main reason for failure. The percentage difference between FEA and experimental results was less than 10%.

Research on the interface and properties of spherical ZTA particles reinforced Fe-Cr-B matrix composite

Spherical zirconia toughened alumina (ZTA) particles reinforced Fe–Cr–B matrix composite was prepared by the liquid phase sintering in the current study. The results demonstrated that at the sintering temperature of 1380 °C, a prominent interface layer was formed between the spherical ZTA particles and the Fe–Cr–B alloy, the thickness of which is about 50 μm. The combined effects of B element, Mn element and SiO2 promote the formation of the interface. Mn2SiO4, Fe2SiO4, MnFe2O4 and B2O3 were formed at the interface. The formation mechanism is described. Hardness and Young's modulus of SZ40 sample at the interface are 12.88 and 146.60 GPa, respectively, which play a crucial role in combining of ZTA particles and the matrix. The wear resistance of the composite prepared in the current study is excellent. The wear volume loss decreases gradually with the increase of spherical ZTA volume fraction. Under the same wear conditions, the volume loss of the SZ40sample is only 9.65% of that of the Cr16 sample and is 14.33% of that of the matrix sample. The spherical ZTA in the composite is higher than the Fe–Cr–B matrix, forming a “shadow effect” to protect the matrix. The Fe–Cr–B matrix has better toughness and can support the spherical ZTA particles during the wear process. Effective combination of the advantages of the two reduces the volume loss of the composite.

Effect of honeycomb structure parameters on the mechanical properties of ZTAp/HCCI composites

Zirconia toughened alumina particles (ZTAp)/high chromium cast iron (HCCI) matrix honeycomb composites were successfully prepared by a non-pressure infiltration casting process. This paper systematically investigates the effect of pore size (6 mm, 8 mm, 10 mm, 12 mm) on the compression resistance of honeycomb structure under the same wall thickness condition. Through the simulation software Ansys Workbench and compression performance test, it was found that the compression performance tends to increase gradually with the increase of the honeycomb pore size, and the optimal compression resistance is reached when the pore size is 12 mm. This optimum performance is attributed to the fact that the reinforcement mechanism of the composite depends not only on the load sharing of the reinforcing particles, but also on the strength of the matrix.

Surface metallization with Ni–Cu bimetal for ZTA by electroless plating

ABSTRACT The surface metallization of zirconia-toughened alumina (ZTA) particles with Ni–Cu bimetallic coatings is performed by electroless plating assisted with choline chloride–ethylene glycol (ChCl-EG) ionic liquid. The possible reactions and deposition sequences of the plating process have been analyzed based on the micro-morphologies of the Ni–Cu coated ZTA (ZTA@Ni–Cu) particles obtained at different reaction stages. The roles of ChCl-EG additive, reaction temperature, and ZTA concentration on the surface morphology, coating thickness, and element content of the ZTA@Ni–Cu particles are also investigated. Results show that uniform cauliflower-characteristic Ni–Cu coatings are formed on ZTA surfaces with 35 g·L−1 ChCl-EG at 65°C. The coating thickness is about 26.9 μm, and the element contents of Cu and Ni are 38.1 at% and 61.9 at%, respectively. Besides, a schematic illustration about the fabrication of ZTA@Ni–Cu particles is proposed to elaborate the formation process of Ni–Cu coatings and the function mechanism of ChCl-EG additive.

Effect of alloy powder on the properties of ZTA particles reinforced high chromium cast iron composites

Micrometer scale zirconia toughened alumina particles (ZTAp) reinforced high chromium cast iron (HCCI) matrix composites were prepared by the non-pressure infiltration casting process, which solved the poor compounding of micrometer scale ceramic particle preforms under seepage. The effects of the microstructure and the mechanical properties of ZTAp reinforced HCCI matrix composites by micro-powder contents in the preforms were systematically investigated. Alloy powder content of 65 wt.%, 55 wt.%, 45 wt.%, 35 wt.% and 25 wt.% was added to the composite material respectively. Phases of the composites was identified by optical microscope (OM), energy dispersive spectrometer (EDS) and x-ray diffraction (XRD). The best compressive properties of the composites were obtained when the content of alloy powder at 45 wt.%, which the strain reached 6.32% with a stress of 1229.63 ± 39.05 MPa. The fracture mechanism of the ZTAp reinforced HCCI composites mainly was brittle fracture and the ductile fracture was minor. This study shows that the addition of micrometer powder was contributed to improve the organization and properties of the ZTAp reinforced HCCI matrix composites. The reinforcement mechanism of composites not only depends on the load sharing of the reinforcing particles, the strength of the matrix was also critical.

Behaviors of ZTA (zirconia toughened alumina) reinforced iron composites under impact abrasive wear conditions

This paper reports our investigation of the behaviours of ZTA (zirconia toughened alumina) particle reinforced iron composite materials (ZTAp/Fe45) during impact abrasive wear tests. The samples were produced by vacuum sintering and tested on an MLD-10 Impact Wear Rig using Fe45 as comparative material. The results show that most ZTAp/Fe45 composites have higher impact wear resistance than Fe45 matrix material due to the impeding role of ZTA particles against the impact of SiO2 abrasives. The wear resistance of ZTAp/Fe45 composites firstly increases and then decreases with the increase of particle size of ZTA, achieving best performance when the ratio between average sizes of the ZTA particles and SiO2 abrasives approaches 0.5. The wear mechanisms of Fe45 matrix material are mainly micro ploughing, impact plastic deformation and fatigue induced flaking. The failure process and mechanism of the ZTA particles are that cracks nucleate and propagate preferentially along the phase boundaries between the alumina and zirconia, resulting in micro peeling-off in the double phase mixture zone and eventually the delamination of alumina grains.

Microstructure and mechanical properties of Fe-ZTA cermet prepared by vacuum hot-pressed sintering

The cermet based on metallic iron with zirconia toughened alumina (ZTA) as the reinforcing phase was prepared by vacuum hot-pressed sintering. The ZTA particles were subjected to electroless nickel plating to improve the interfacial bonding ability of ZTA and Fe matrix. In this paper, after electroless nickel plating, the effects of different particle sizes and different contents of ZTA particles on the grinding properties of Fe-based ZTA (Fe-ZTA) cermets were investigated. The results show that the ZTA particles are tightly bound to the Fe matrix. An interface layer is formed between the ZTA particles and the Fe matrix and it can improve the grinding ability of the Fe-ZTA cermet. By reducing the particle size and the content of ZTA particles, the friction coefficient between Fe-based ZTA cermet and the machined surface can be increased, and the surface roughness of the machined surface will reduce. When the ZTA particle size is F14 and the iron binder content is 40%, the friction coefficient between the Fe-ZTA cermet and the steel bar is 0.4981, the surface roughness of steel bar is 40.164 μm, the grinding ratio is 685.952.

Growth behavior of aluminum borate whiskers on zirconia toughened alumina (ZTA) particle surface

In this work, B4C-covered zirconia-toughened alumina (ZTA) particles are prepared and oxidised at 1050 °C for different times (0, 2, 4, and 8 h) in air. The X-ray diffraction and electron probe micro-analysis results show that the covering layer is mainly composed of oxide B2O3 intermetallics, residual B4C particles, and Al18B4O33 whiskers. The scanning electron microscopy results show that the growth of Al18B4O33 whiskers on the ZTA particles enhances with increasing heat preservation time; the optimum holding time is determined to be 8 h Al2O3 in the ZTA particles diffuse into the covering layer and combine with B2O3 to form Al18B4O33 whiskers; the Al18B4O33 whiskers grow via the liquid-solid mechanism.

Effects of preform aperture/hole wall ratio on the microstructure and properties of ZTAp/HCCI matrix honeycomb structure composites

Zirconia toughened alumina particles (ZTAp)/high chromium cast iron (HCCI) matrix honeycomb structure composites were successfully prepared by the non-pressure infiltration casting process. The transformations of ZTA ceramic particles and high chromium cast iron during the compound process were analyzed by using x-ray diffraction (XRD) and Electron probe microanalysis (EPMA). The maximum stress and average value of the maximum stress simulated by COMSOL Multiphysics software shows a trend of decreasing first and then increasing with decreasing preform aperture/hole wall ratios. The maximum stress and average value of the maximum stress are minimal among the six comparison groups and the stress range is 0.8 ∼ 1.8 GPa with preform aperture/wall ratio of 1.25. Owing to the change in the main impregnation resistances influenced by the hole wall value, the dispersion uniformity of ZTA ceramic particles in the composites becomes better with preform aperture/wall ratio of 1.43, 1.25 or 1.11. When the preform aperture/hole ratio is 1.25, the compressive strength of the samples reaches a maximum value of 1240 MPa. And the trend of the compressive mechanical properties is consistent with the results of the stress simulation. The wear volume loss of the composites reaches the smallest with preform aperture/hole wall ratio of 1.25, because the protective effect of ZTA ceramic particles and the supporting effect of high chromium cast iron achieve the best synergistic cooperation at this ratio.

Interfacial Bonding and Abrasive Wear Behavior of Iron Matrix Composite Reinforced by Ceramic Particles.

Using zirconia toughened alumina (ZTA) particles and Ni–Ti complex powders as raw materials, high-Cr cast iron reinforced by ZTA particles was prepared by an infiltration casting process. A continuous transition layer formed at the interface between ZTA particles and the Cr15 matrix, which proves that there is strong metallurgical interfacial bonding at the interface. The phases in the Ni–Ti layer of the ZTAP/Fe composite were preserved compared with the microstructure of sintered ZTA ceramic preform. The hardness of the Ni3Ti, TiO and AlNi2Ti phases in the interfacial transition layer was measured by the nano-indentation method, which is 12.5 GPa, 16.1 GPa and 9.2 GPa, respectively. The three-body wear resistance of the composite reached 12.6 times that of high-Cr cast iron.

Temperature and stress field analysis of solidification process in high chromium cast iron matrix composite reinforced by ZTA ceramic particles

As the melted iron and zirconia toughened alumina particles are non-invasive, it is always a critical problem to realize the infiltration between melted iron and ceramic particles. The solidification process of high chromium cast iron matrix composites reinforced by zirconia toughened alumina ceramic particles by infiltration casting is simulated using finite element analysis method in this paper. Two physical modules, heat transfer in solid and solid mechanics are used to describe the solidification phenomenon. The variation and distribution of stress field and temperature field during solidification are analyzed. By comparing the stress of different diameter/wall thickness ratio, the optimal diameter/wall thickness ratio for performance is found to be 1.5 to realize the infiltration process. Compared with the experimental results, it shows that the simulation results are in accordance with the experiments results, so the established model and simulation methods are correct, and can provide the foundation for the further research.

Fabrication and wear behavior of ZTA particles reinforced iron matrix composite produced by flow mixing and pressure compositing

A high chromium cast iron (HCCI) matrix composite reinforced with zirconia-toughened alumina (ZTA) particles was fabricated via rapid–flow mixing followed by high–pressure compositing (FM-PC) technique, which required neither particle coating nor the use of preforms. The microstructure, mechanical properties and impact-abrasion wear resistance of the composite were investigated. The integrity of the composite without obvious defects was demonstrated, a uniform distribution of ZTA particles in the HCCI matrix and a tight mechanically bonded interface between particles and matrix were obtained. The composite exhibited better wear performance than HCCI under different energies, and the relative wear resistance was 2.35 to 1.74 times when the impact energy varied from 1.5 to 4.5 J. The wear mechanisms of the composite were mainly furrow, cutting and fragmentation of reinforced particles under a low impact energy (1.5 J). Conversely, when the impact energy increased to a high value (4.5 J), fragmentation and shedding of the particles, spalling pits and embedding of abrasive particles dominated the wear process.

Wettability and interaction mechanism for Ni-modified ZTA particles reinforced iron matrix composites

The wetting behaviors of bare and Ni-modified zirconia toughened alumina (ZTA) with molten iron matrix have been explored by sessile drop technique and gathered to compare their wettability. Experimental results show that the wetting angles of molten 65Mn steel and high chromium cast iron (HCCI) matrix on bare ZTA substrates are 104.1° and 102.3°, respectively, whereas it is decreased to 83.6° and 88.2° on Ni-modified ZTA substrates. The wetting angle of HCCI matrix on Ni plate is just 1.5° in 1 min. At high casting temperature, element Ni originated from Ni coating can diffuse into molten Fe and keep constant basically. Small amount of element Ni can react with Al2O3 on ZTA/Fe interface to form Al2NiO4. A schematic illustration of the cast-infiltration process is put forward, which indicates that Ni-modified ZTA can be wetted with molten iron through Ni diffusion and reactive wetting. A ZTA/Al2NiO4/Fe interface layer is formed by mechanical bonding, interdiffusion and small amount of chemical reactions, to achieve composites with tight interfacial bonding strength. Besides, Ni-modified ZTA particles are prepared through electroless plating assisted with Ethaline additive and used as precursor to reinforce 65Mn steel matrix composite by nonpressure casting infiltration method.

Effect of ZTA volume fractions on the microstructure and properties of ZTAp/high manganese steel composites

The non-pressure casting infiltration technique was used to fabricate ZTA (zirconia toughened alumina) reinforced high manganese steel composites in order to study the influence of ZTA volume fractions on the microstructure and properties of it. The grain size of matrix in recombination region reduces from 154.4 μm to 63.2 μm when the volume fraction of ZTA particles increases from 0% to 32.8%. The Rockwell hardness and yield strength of the composites were found to be strongly dependent on the volume fraction of ZTA particles. The compressive strength of composites is closely related to the distribution of ceramic particles and the expansion of cracks around the particles. The interfacial layer of composites can absorb the stress from the ZTA ceramics and the metal matrix during the thermal expansion and contraction. The composites with 24.3 vol% ZTA showed the highest the impact abrasive wear and its wear loss is 2/3 times than that of high manganese.

Microstructure and properties of interfacial transition zone in ZTA particle–reinforced iron composites

The interfacial transition zone (ITZ) in the zirconia toughened alumina (ZTA) ceramic particles reinforced the high chromium cast iron composites was studied. The main phases are Na4SiO4 and 3Al3O2·2SiO2 in the ITZ were identified by XRD, TEM, and HRTEM. The hardness and the elastic modulus of the ITZ were examined by nanoindentation test are 7.11 GPa and 202.68 GPa, respectively. The results show that the Fe and Mn diffused from the ZTA particles and matrix into the ITZ. The interface bonding strength of ZTA/ITZ and ITZ/matrix is stronger than the middle region of the ITZ.

Wear Behaviour of Iron Matrix Composite Reinforced by ZTA Particles in Impact Abrasion

Zirconia toughened alumina (ZTA) particles reinforced high chromium cast iron composites (ZTA/Iron composites) were prepared by a two-step processing method, i.e. mixing particles by the molten metal and cohering by high pressure, which based on the squeeze casting process. The impact wear resistance under different impact energies were investigated using dynamically loaded abrasive wear tester at room temperature. For comparison, the wear tests of high chromium cast iron were also carried out under the same conditions. Worn surfaces of the samples were observed under scanning electron microscopy equipped with an energy dispersive detector. The results showed that the composites have better impact wear resistance than that of high Cr cast iron regardless of impact energy level, and the wear resistance of the two materials all decrease with the increase of the impact energy. The main wear mechanisms of the high Cr cast iron were micro-cutting and fatigue peeling, while the wear of composites occurred through micro-cutting of the matrix (lower impact energy) and breaking and shedding of the reinforced particles (higher impact energy).

Mixture of fuels approach for the solution combustion synthesis of Al 2O 3–ZrO 2 nanocomposite

A modified solution combustion approach was used for the first time in the preparation of nanosize zirconia toughened alumina (ZTA) composite. ZTA-1 with an average particle size of ∼37 nm was prepared using corresponding metal nitrates and urea. ZTA-2 with an average particle size of <10 nm was prepared by using mixture of fuels such as ammonium acetate, urea and glycine. The products formed were characterised by powder X-ray diffractometry, Transmission electron microscopy and BET surface area analysis. By using mixture of fuels, the energetics of the combustion reaction and eventually the properties of the combustion product have been changed. A series of combustion reactions were carried out to optimise the fuel ratio combinations required to obtain <10 nm ZTA particles. The microstructure of ZTA consisted of crystallites of Al 2O 3 and ZrO 2 both of which were nanocrystalline as evident from TEM.