High Chromium Cast Iron Matrix Research Articles

Effect of B4C on wear behaviour of ZTA ceramic reinforced high chromium cast iron matrix composites

Zirconia Toughened Alumina (ZTA) ceramic reinforced high chromium cast iron (HCCI) matrix composites were prepared by vacuum pressure-free infiltration, and the effects of active additive B4C (10%, 12%) on the interface binding ability and three-body wear behaviours was study systematically. Result showed the wettability between HCCI and ZTA could be improved after the addition of B4C, which could result in a metallurgical combination by forming a transition layer. When the content of B4C additive was 10%, the Brinell hardness (HB) of ZTA/HCCI composite materials reached 645 N/mm2 in the as-infiltration state, and the wear resistance was more than three times of HCCI. After heat treatment, the hardness and wear resistance increased significantly, which could reach 676.1 N/mm2 and more than five times of HCCI, respectively.

Study on the microstructure and properties of iron-based composites locally reinforced by in-situ submicron TiC particles

This study discussed the strengthening mechanism of in-situ submicron TiC particles on high chromium cast iron matrix composites. By changing the Ti content, the microstructure evolution and performance change law of the composites are analyzed. The results show that the average particle size of the TiC particles will grow with the increase of the Ti content in the preforms. After the in-situ reaction, there will be a transition layer of 20–30 μm in the interfacial zone of the composite, and a high density of dislocations will appear at the same time. Furthermore, the presence of submicron TiC particles in the microstructure can significantly improve the strength and wear resistance of the composites. By contrast, only the Ti content in preforms is 50%, the microstructure and performance of the test steel (S2 steel) are the most ideal. The TiC particles in the composite area account for more than 70%, and the hardness is as high as 1236 HV, which is more than twice the hardness of the matrix. Under the same wear conditions, the mass loss and wear rate of S2 steel are the smallest, which are only 0.2 ± 0.1 mg and 3.08 × 10−6 ± 0.05 mm3/Nm, respectively.

Study on microstructure and abrasive wear properties of in-situ TiC reinforced high chromium cast iron matrix composite

In this paper, the TiC particle-reinforced high chromium cast iron matrix composite was prepared in situ by the method of injection infiltration, and the effect of adding different volume fractions of moderators on the size of the reinforcing particles, the volume fraction of the reinforcing particles and the abrasive wear of the composite was systematically studied. Performance impact. The research results show that the TiC particles obtained by the in situ method are uniformly distributed in the matrix of high chromium cast iron, and the interface between the particles and the matrix is clean. And as the volume fraction of the moderator increases, the size of the obtained TiC particles becomes smaller and more uniform, and the volume fraction of the reinforcing particles also gradually decreases with the increase of the volume fraction of the moderator. And the introduction of TiC has increased the hardness of the material by up to 69.036%. Abrasive wear experiments show that the introduction of the moderator makes the reinforcing particles smaller, which further improves the wear resistance of the composite material, and the composite material with 20% moderator content has the best wear resistance, compared to The wear resistance of the metal matrix material is increased by 1.8 times.

Effect of B4C on bending strength of ZTA ceramic reinforced high chromium cast iron matrix composites

ABSTRACT Zirconium dioxide-toughened aluminum oxide (ZTA) ceramic-reinforced high chromium cast iron (HCCI) matrix composites were prepared by vacuum pressure-free infiltration, and the effects of active additive boron carbide (B4C) (10%, 12%) on the interface binding ability was studied systematically. Results showed the wettability between HCCI and ZTA could be improved after the addition of B4C, which could result in a metallurgical combination by forming a transition layer. When the content of B4C additive was 10%, the Brinell hardness of ZTA/HCCI composites reached 645 N/mm2 in the as-infiltration state, and the bending strength was more than twice of HCCI. After heat treatment, the hardness and bending strength increased significantly, which reached 676.1 N/mm2 and more than three times of HCCI, respectively.

Nanoindentation and microstructure of interfacial layer in Ni-NiTi coated zirconia toughened alumina particles reinforced high chromium cast iron matrix composites

The Ni-NiTi coated zirconia toughened alumina particles (ZTAp@Ni-NiTi) are prepared by electroless Ni plating and NiTi electroplating in succession. And the ZTAp@Ni-NiTi reinforced high chromium cast iron matrix composites (ZTAp@Ni-NiTi/HCCI) with tight interfacial bonding are produced by nonpressure casting infiltration. X-Ray Diffraction results show that an interface layer, containing new phases of Ti2O3, TiO, Ni3Ti, NiTi2, NiTi and FeCrNi, is formed between the HCCI matrix and ZTA particles. The hardness and Young’s modulus of the interfacial layer in ZTAp@Ni-NiTi/HCCI are 5.691 GPa and 224.707 GPa, respectively. Compared to ZTA particles reinforced high chromium cast iron matrix composites, a high modulus of the interface layer can effectively ease the unevenness of plastic deformation in ZTA reinforcement and HCCI matrix, exhibiting an excellent comprehensive nanomechanical property.

Compression Performance and Abrasive Wear Resistance of CuNi‐Modified Zirconium Oxide‐Toughened Alumina Particles‐Reinforced Iron Matrix Composites

Compact and continuous Ni‐coated zirconium oxide‐toughened alumina (ZTA) particles (ZTAp@Ni) and CuNi‐coated ZTA particles (ZTAp@CuNi) are prepared by electroless deposition. The thicknesses of the Ni and CuNi coatings are 6.84 and 21.35−43.10 μm, respectively. The ZTAp@Ni‐ and ZTAp@CuNi‐reinforced high‐chromium cast iron (HCCI) composites are fabricated by nonpressure cast‐infiltration method. Results show that compact interfacial bonding is formed in S3′‐ZTAp@CuNi/HCCI without any casting defect. The addition of Ni element can effectively improve the amount of (Cr,Fe)7C3 and refine the grains in HCCI matrix, and Cu element can improve the strength and toughness of the matrix. The compression performance testing shows that the compressive strength and yield strength of S3′‐ZTAp@CuNi/HCCI are up to 1128.03 and 1049.40 MPa, respectively. In addition, three‐body abrasive testing demonstrates that the abrasive wear resistance of the S3′‐ZTAp@CuNi/HCCI is optimal. This can be attributed to the compact combination between ZTAp@CuNi and HCCI matrix, which benefits the load transfer and the protection of ZTA particles to avoid brittle fracture and debonding. So, the appropriate additions of Cu and Ni elements, that is, the thickness and content control of CuNi coatings on ZTA surfaces, are very crucial for the performance improvement of composites.

Interfacial characterization and erosive wear performance of zirconia toughened alumina ceramics particles reinforced high chromium white cast irons composites

To investigate the erosive wear-corrosion behavior of ZTAP ceramic reinforced high chromium cast iron matrix composites in two types of sand at various rotational speeds, the ZTAP/Fe composites were fabricated. The interface characteristics, erosion wear-corrosion and erosive wear mechanism have been investigated in a slurry condition at various erosion rotational speeds. The chemical composition of the matrix material was determined using a spark spectrometer. SEM, TEM, 3D laser scanning microscope and AFM were used to analyze the microstructure characteristics and worn surface morphology of the composites. Furthermore, the wear loss rate and relative erosive wear resistance of ZTAP/Fe composites and Cr15 standard specimen measurements were conducted. The results showed that the interface between the ZTAP ceramics and the Cr15 matrix exhibits a continuous transition layer without visible defects and close contacts. In the case of SiO2 and SiC abrasive sand, the wear rate of ZTAP/Fe composites and Cr15 standard specimens increases with erosion time. The wear rate of ZTAP/Fe against SiO2 sand is lower than that of against SiC sand. ZTAP/Fe composites was found to exhibit a better corrosion resistance property than that of Cr15 standard specimens.

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.

Effects of manganese on diffusion and wear behavior of ZTA particles reinforced iron matrix composites in vacuum

Different volume fraction ZTA particles reinforced high chromium cast iron (HCCI) matrix composites were fabricated by liquid phase sintering (LPS) in vacuum of −0.1 atmospheric pressure. The influence of manganese on the microstructure, phase constituents and mechanical properties of the ZTA particles reinforced HCCI composites was investigated by means of SEM, XRD, and nanoindentation tests. The results demonstrated that the interfacial layer with a thickness of 25–35 μm was formed between ZTA particles and HCCI matrix, combined the effects of manganese additions. The elements in the interfaces layer are mainly Mn, Si, Zr and Al with a small amount of Fe. New phases formed by MnO acting on the surface of ZTA particles and the interfaces were MnO2·Al2O3, Mn2SiO4 and MnFe2O4. However, in the interfaces layer near the matrix, MnO was reduced by C to form Mn and Mn3C and dissolved in HCCI matrix. The hardness and modulus of the interfacial layer were 20.25 GPa and 294.7 GPa, respectively. The wear mass losses of Cr20 sample is about 4.7 times higher than that of 40 vol% ZTA particles reinforced iron matrix composites.

Microstructure and wear properties of SiC woodceramics reinforced high-chromium cast iron

Wood ceramization is a promising preparation technology. Ceramics made from natural wood can retain the original structural characteristics and unique microstructure of the wood, and also offer acceptable mechanical properties and wear resistance. In this study, the ceramization process of natural poplar wood is optimized. Three-dimensional silicon carbide prepared by ceramization of wood is used to strengthen high-chromium cast iron, and three-dimensional silicon carbide reinforced high-chromium cast iron (3D-SiC/HCCI) composite materials are obtained. The results demonstrate that the treated wood retained acceptable network structure and uniform pore size after ceramization. Based on the size, the pores can be classified into smaller pores (approximately 8 μm), medium-sized pores (20–40 μm), and larger pores (100–300 μm). The 3D-SiC/HCCI composites, obtained by casting and infiltrating these pore channels, show continuous network-like interpenetrating structures in space. The wear resistance of the 3D-SiC/HCCI composite materials was investigated and compared with high-chromium cast iron. The results indicate that under the same friction condition, the wear resistance of the composites is significantly improved, and the abrasion loss is reduced from 3.8% to 0.32%. The three-dimensional silicon carbide in the composites produces a shadow effect during friction, which can provide acceptable support and protection for the high-chromium cast iron matrix.

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.

Preparation and Properties of High Chromium Cast Iron Matrix Composites Reinforced by Zirconium Corundum Particles

In this paper, the zirconia corundum ceramic particles reinforced high chromium cast iron matrix wear resistant composite material was produced by vacuum infiltration casting. The experimental results show that the nickel plating on the surface of the ceramic was beneficial to the infiltration of the molten metal. The interface of the composite was dense without defects and uniform particle distribution in the composite. Based on the dynamic analysis of the infiltration process, the mechanism of casting infiltration was expounded detailedly. The friction and wear experiments show that the wear resistance of the composites is 1.93 times of high chromium cast iron and the life was greatly improved. The morphology analysis results show that the wear resistance of the composites was low stress abrasive wear, so the wear mechanism was micro cutting of abrasive grains.

Modification of ZTA particles with Ni coating by electroless deposition

The modification of ZTA particles with Ni coating as reinforcement is systematically clarified to enhance the wearability of Ni-encapsulated ZTA (ZTA@Ni)-reinforced high-chromium cast iron (HCCI) matrix composites. Continuous and uniform metallic Ni coatings are formed on ZTA surface by electroless deposition with ChCl-EG ionic liquid as additive. The coating thickness can be controlled by regulating deposition times and the ZTA@Ni particles with 24.35 μm are chosen as reinforced phase in HCCI matrix composites. Results show that Ni atoms can be permeated into matrix during the casting process leading to the formation of diffusive nucleus to refine the particle size of carbides adjacent interface. A good combination between ZTA@Ni particles and HCCI matrix is observed in the composites. The dissolution and diffusion of metallic Ni can greatly reinforce the interfacial bonding strength to constitute a compact combination of the metallic phase and hard phase.

Numerical simulation of mold filling process for high chromium cast iron matrix composite reinforced by ZTA ceramic particles

The mold filling process of high chromium cast iron matrix composites reinforced by zirconia toughened alumina (ZTA) ceramic particles (referred as HCCI/ZTAP composites hereinafter) by infiltration casting were simulated using finite element analysis software in this paper. Volume of fluid (VOF) method and porous medium model were used to describe the flow phenomenon during infiltration process. Multiphase flow and heat transfer equations were solved by finite element method. The comparison between the experimental observations and simulation results indicates that the formulated model and method could provide a solution with acceptable accuracy, thus a promising tool to optimize the processing parameters. After trial calculations, the optimal parameters and pouring system were determined eventually. A complete casting without any defects was prepared at the pouring temperature of 1843K and pouring velocity of 0.2m/s by top filling in an enclosed gating system.

Three-body abrasive wear resistance of iron matrix composites reinforced with ceramic particles

Pure aluminum oxide (Al2O3), ZrO2 toughened Al2O3 (ZTA; 25–30% ZrO2), and ZTA (55–60% ZrO2) ceramic particles reinforced Cr25 matrix composites are successfully fabricated by the infiltration casting process. The volume fraction of ceramic particles in the composites is 47–55%. The interface structure between ceramic particles and the matrix was analyzed by digital probing microscopy and was found to be continuous mechanical bonding. The wear behavior of the composites was studied by a three-body abrasive wear tester. ZTA (55–60% ZrO2) reinforced Cr25 composite has excellent wear resistance which is approximately six times higher than that of the high chromium cast iron matrix. It is discovered that the wear mechanism of composites is micro-cutting and fatigue stripping. A correlation exists between the wear resistance of composites and the strength of ceramic particles.

Optimization of Abrasive Wear Behavior of High Chromium Cast Iron and Hadfield Steel

Abstract: Wear properties of two different crushers used for grinding raw materials of cement industry are compared us-ing pin on disk wear test. The wear test was carried out with different loads on a pin. Abrasive wear behavior of two crushers made of Hadfield steel and high chromium cast iron was evaluated by comparing weight loss, wear resistance, microhardness and friction coefficient. The results showed that abrasive wear of high chromium cast iron was lower than Hadfield steel because of the larger amount of carbides and higher work hardening in the steel at the higher applied loads. Increase in surface hardness of Hadfield steel was more noticeable compare to high chromium cast iron due to the work hardening and formation of the twining sites during the wear test. Owing to the presence of M 7 C 3 carbides in high chro-mium cast iron matrix, impact crushers exhibited higher friction coefficient. In addition, a wear loss equation was derived based on a real crushing condition. However, a new approach in optimization of the wear parameters was developed and wear behavior of the materials was predicted based on the maximum number of the effective factors. The optimization of the parameters by genetic algorithm showed that optimum wear loss for hammer and impact crushers under real condition is 5.2958 mg and 3.8449 mg, respectively. Results of the numerical simulation show that the genetic algorithm optimiza-tion is effective and very useful in designing the hammer and impact crushers. In addition, some recent patents on abra-sive wear behavior of the high chromium cast iron and Hadfield steel are discussed in details.

Optimization of Abrasive Wear Behavior of High Chromium Cast Iron and Hadfield Steel

Wear properties of two different crushers used for grinding raw materials of cement industry are compared using pin on disk wear test. The wear test was carried out with different loads on a pin. Abrasive wear behavior of two crushers made of Hadfield steel and high chromium cast iron was evaluated by comparing weight loss, wear resistance, microhardness and friction coefficient. The results showed that abrasive wear of high chromium cast iron was lower than Hadfield steel because of the larger amount of carbides and higher work hardening in the steel at the higher applied loads. Increase in surface hardness of Hadfield steel was more noticeable compare to high chromium cast iron due to the work hardening and formation of the twining sites during the wear test. Owing to the presence of M7C3 carbides in high chromium cast iron matrix, impact crushers exhibited higher friction coefficient. In addition, a wear loss equation was derived based on a real crushing condition. However, a new approach in optimization of the wear parameters was developed and wear behavior of the materials was predicted based on the maximum number of the effective factors. The optimization of the parameters by genetic algorithm showed that optimum wear loss for hammer and impact crushers under real condition is 5.2958 mg and 3.8449 mg, respectively. Results of the numerical simulation show that the genetic algorithm optimization is effective and very useful in designing the hammer and impact crushers. In addition, some recent patents on abrasive wear behavior of the high chromium cast iron and Hadfield steel are discussed in details. Keywords: Abrasive wear, genetic algorithm, Hadfield steel, hammer crusher, high chromium cast iron, impact crusher, optimization, wear resistance

Abrasive Wear Behavior of High Chromium Cast Iron and Hadfield Steel—A Comparison

Wear properties of two different crushers used for grinding raw materials of cement industry are compared using pin-on-disk wear test. The wear test was carried out with different loads on a pin. Abrasive wear behavior of two alloys was evaluated by comparing mass loss, wear resistance, microhardness and friction coefficient. The microstructure of the specimens was detected using optical microscope. The results showed that abrasive wear of high chromium cast iron is lower than that of Hadfield steel. Due to the presence of M7C3 carbides on the high chromium cast iron matrix, impact crushers exhibited higher friction coefficient.