Ceramic Particle Reinforced Metal Matrix Research Articles

Microstructure evolution and mechanical properties of TiB2/18Ni300 composite material produced by laser additive manufacturing

As a reinforcing phase, TiB2 exhibits exceptional wettability and stability when mixed with steel matrices, making it an ideal reinforcement for steel matrix composites. In this paper, we add TiB2 for additive manufacturing of 18Ni300 steel for weight reduction and reinforcement. TiB2 reinforced 18Ni300 matrix composites were prepared by laser cladding. SEM, EDS, and XRD were used to observe the joints' interface and fracture characteristics and analyse the substance composition. Tissue analysis was then performed using EBSD and TEM. According to the TEM and XRD results, there is a martensite structure within the cell, and the cell boundary is an austenite structure. After adding TiB2, a reinforcing phase ((Mo, Fe)3B2) is distributed at the boundary of the cell structure. The high hardness of boride increases the microhardness of the composite material. The yield strength, modulus, and elongation of the samples prepared with 18Ni300 powder are lower than that of forged 18Ni300, but the tensile strength reaches 1134 MPa. The addition of TiB2 increases the composite material's yield strength and elastic modulus significantly. This strengthening technique, which employs the addition of ceramic particles to martensitic steel, is currently not widely used. This experiment provides a theoretical basis and process reference for preparing high-stiffness and lightweight ceramic particle reinforced metal matrix composites.

Effect of the in-situ formed CuO additive on the fracture behaviour and failure mechanism of Ag-SnO2 composites

Oxide additives can significantly improve the mechanical properties of ceramic particle-reinforced metal matrix composites. In this study, the fracture behaviour and failure mechanism of the Ag-SnO2 composites without and with in-situ formed CuO additive are investigated using in-situ scanning electron microscope (SEM) and numerical simulation. The results show that the CuO additive significantly enhances the fracture toughness of the Ag-SnO2 composite. The initiation and propagation of secondary cracks near the primary crack tip are effectively inhibited, and large dimples are formed around SnO2 particles. The improvement in the mechanical properties is attributed to the stress concentration relief in the Ag matrix and enhanced interfacial strength. Interface debonding at the sharp corners of the SnO2 particles initiates the formation of cracks in the Ag-SnO2 composite without CuO. The initiated cracks propagate through the high-stress concentration region at an angle of 45° to the loading direction, resulting in a matrix fracture. For the Ag-SnO2 composite with CuO nanoparticles, the propagation rate of the primary cracks reduces significantly, and microcracks are primarily induced near clustered SnO2 particles. Moreover, the damage initiation shifts from the SnO2/Ag interface to the Ag metal matrix with reduced SnO2 particle aggregation in the Ag-SnO2(CuO) composite.

Effect of strength and toughness of ceramic particles on impact abrasive wear resistance of iron matrix composites

The wear resistance of ceramic particle reinforced metal matrix composites is closely related to the properties of ceramic particles. In this study, three kinds of ceramic particle (with 30 % volume fraction) reinforced iron matrix composites (Al2O3/Fe45, ZTA(Zirconia toughened alumina ceramic particles)/Fe45 and ZrO2/Fe45) were prepared by powder metallurgy method. The mechanical properties, impact abrasive wear resistance and impact abrasive wear mechanism of the composites were studied, and the phase transformation of ceramic particles in the composites was analyzed. The results show that the elastic modulus and hardness of ZTA/Fe45 composite are between Al2O3/Fe45 and ZrO2/Fe45, which are 248.5 GPa and 13.3 GPa, respectively. The ZTA/Fe45 composites exhibit a better impact wear resistance than the other two composites. The impact abrasive wear resistance of the three kinds of composites is positively correlated with the product value of fracture toughness and hardness (H·KIC) of ceramic particles. The wear mechanism of the Fe45 matrix of the composite is micro-furrow and plastic deformation. The brittle fracture and spalling of Al2O3 ceramic particles occur after impact abrasive wear, forming spalling pits and accelerating the wear of Al2O3/Fe45 composites. ZrO2 ceramic particles lead to easy removal from the Fe45 matrix due to lower hardness after impact abrasive wear. ZTA ceramic particles protruded from the surface of the Fe45 matrix after impact abrasive wear. On the surface of ZTA particle, the irregular protuberant steps morphology are formed by SiO2 abrasive impact and tangential wear. The ZTA and ZrO2 ceramic particles in the worn surfaces of the composites undergo t-ZrO2 to m-ZrO2 phase transformation during the impact wear, and the t→m phase transformation content is related to the impact energy. The amount of phase transition increases with the increase of impact energy, When the impact energy is higher than 2J, the amount of phase transition tends to be stable. Under the same impact energy, the amount of t→m phase transition in ZrO2 particles is much lower than that in ZTA. The t→m phase transformation increases the toughness of ZTA particle，improving the impact abrasive wear resistance of ZTA/Fe45 composite.

Experimental study on laser assisted ultrasonic elliptical vibration turning (LA-UEVT) of 70% SiCp/Al composites

SiCp/Al composites are more and more used in aerospace, military industry and other industries. However, the surface integrity of materials is poor, and the cutting force is large as the anisotropy of materials in the traditional machining (TM) process, which hinders the application of ceramic particle reinforced metal matrix composites. With the requirement of high dimensional accuracy, high efficiency and low damage for materials in these fields, non-traditional machining technology has become a research hotspot. Laser assisted machining (LAM) is a non-contact special machining method. Its advantages in machining SiCp/Al composites have been proved by experiments, but there are still processing defects such as thermal cracks. Therefore, to further improve the machining quality of 70% SiCp/Al composites with high volume fraction, a new machining method combining ultrasonic elliptical vibration turning (UEVT) and laser heating assisted turning (LAT) is proposed. High frequency intermittent machining and the adjustment of laser temperature influence on materials can be realized by adjusting the ultrasonic amplitude. Combining the characteristics of the two processing techniques, the feasibility study of the new machining method was studied by turning experiments. In this paper, compared with TM and LAT, the removal mechanism of materials and the effects of different laser heating temperatures and ultrasonic vibration on cutting force, surface quality, subsurface damage and chip morphology are explored. The results show that LA-UEVT can effectively reduce the cutting force and surface roughness, improve the plastic removal ability, and inhibit surface and subsurface damage. And the material removal process is mainly in the form of small particle crushing and particle pressing, which improves the stability of cutting force in the cutting process.

Mechanical and corrosion properties of additively manufactured SiC-reinforced stainless steel

Laser additive manufacturing (LAM) provides an opportunity for the in-situ preparation of high-performance ceramic particle-reinforced metal matrix composites (MMCs) with complex shapes. 316L stainless steel has excellent corrosion resistance but suffers from low strength and poor wear resistance, limiting its wide application. Here, laser powder bed fusion (LPBF) of SiC-reinforced 316L metallic matrix composites (MMCs) for obtaining better mechanical and corrosion properties were investigated, and the role of SiC contents on the microstructures and properties were discussed in detail. Besides, the post heat treatment was conducted to further improve the mechanical properties of MMCs. The micron-sized SiC is refined to the nano-level, together with the formation of many dislocations in the matrix during the LPBF process. The addition of SiC significantly improves the strength of 316L, with the highest tensile strength up to 1.3 GPa. The 6 vol% SiC-reinforced MMC reaches a tensile strength of 1069 MPa and an elongation of 9% while keeping a similar corrosion resistance with 316L. The heat treatment achieves a better strength-ductility in the 6 vol% SiC-reinforced MMCs, in which the tensile strength is slightly reduced to 900 MPa, but the elongation increased significantly to 18.4% due to the release of residual stress and reduction of dislocation density. In addition, the underlying strengthening mechanism and corrosion behaviour are investigated.

Comparison of the effects of Mg and Zn on the interface mismatch and compression properties of 50 vol% TiB2/Al composites

Low ductility limits the extensive application of high volume fraction (>30 vol%) ceramic particle-reinforced metal matrix composites, and the simultaneous improvement of strength and ductility is still a challenge owing to the smaller amount of matrix contained in such composites. In this paper, the effects of various contents of Mg or Zn (0, 6, 10 and 14 wt%) on the interface mismatch and compression properties of 50 vol% TiB2/Al composite fabricated in situ are comparatively studied. The results indicate that Mg has a better refinement effect than Zn on the TiB2 ceramic particles. Mg can reduce the crystallographic mismatch degree of the Al/TiB2 interface. 6 wt% Mg simultaneously increases the σ0.2, σUCS and εf of the composite into 780 MPa, 1162 MPa and 10.68%, compared with the composite without the addition of Mg, increasing 8.5%, 2.8% and 30.6%, respectively. However, the addition of Zn leads to serious distortion of the Al lattice and deteriorates the interface matching degree of Al/TiB2, so the addition of Zn generally improves the σ0.2 and σUCS while sacrifices the plasticity simultaneously. Furthermore, the contributions of various strengthening mechanisms of the matrix in the high volume fraction TiB2/Al composites are analyzed through a comparative study.

Investigating the effect of carbon interfacial layer on the elastoplastic response of ceramic particle-reinforced metal matrix composites

Titanium-based composites with their desirable and great mechanical properties are in high demand. One of the main problems that arise in this field is the chemical reactions that appear between strengthening the material and the matrix that usually undermines the integrity of the composite. This problem will result in dangerous defects such as debonding or degradation of the properties. In this work, a coating solution is presented; a similar process as discussed in the literature yet analytically different. The coating is commonly used for protecting and preserving the reinforcing material’s surface which is in contact with the matrix. Herein, a titanium metal matrix composite reinforced with carbon-coated SiC particles is discussed. Mori-Tanaka method was utilized to firstly determine the properties of the inclusion which is the carbon-coated SiC particle and then using the results based on the thickness of the coating and volume fraction of inclusions, calculating the overall properties of the composite. An incremental method was employed to then calculate the stress-strain curve of the said material. The results obtained were in good agreement with the experimental data. The negative effect of the carbon coating on the elastic properties of the SiC/titanium composite was observed as the coating layer thickness increased. The same thing was observed in the stress-strain curve in the slope of the elastic zone and work hardening growth in the plastic zone.

Experimental and FEM study of cutting mechanism and damage behavior of ceramic particles in orthogonal cutting SiCp/Al composites

To study the removal mechanism and damage behavior during the machining of ceramic particle-reinforced metal matrix composites, a finite element model (FEM) comprehensively considering the distribution and shape of the particles and the damage behavior of ceramic particles is established. Corresponding experiments are conducted to demonstrate the reliability of FEM. The results demonstrate that chips are easy to separate where the particles gather. The stress concentration is serious at the edges and corners of the particles. The cutting and thrust force, subsurface damage, surface roughness and maximum profile peak-valley height increase with the increase of depth of cut. Voids, particle fracture, particle peeling off, matrix tearing and interface failure are the main surface defects. Moreover, according to the failure mode and mechanism of ceramic particles, the positional relationships between the ceramic particles and the tool are divided into three categories: the particle is below, on and above the cutting path.

An enhanced strength Ni matrix composite reinforced by a 3D network structure of TiN nano-particles

Strengthening is a critical issue for improving the mechanical properties of ceramic particles reinforced metal matrix composites (CPRMMCs). A Ni matrix composite reinforced by TiN nano-particles (TiNNP) with a three-dimensional (3D) network structure was synthesized via low-energy ball-milling (LEBM) and spark plasma sintering (SPS). The ultimate tensile strength (UTS) of the TiN/Ni composite is 690 MPa, an increase of 383% compared to that of the Ni matrix. The 3D network structure of TiN nano-particles formed at the grain boundaries refines the grains significantly and generates a high density of dislocations near the TiN/Ni interface, synergistically contributing to the enhanced strength. Ceramic particles of 3D network structure may be a potential solution to achieving superior properties of CPRMMCs.

Optimization of machining parameters of wire-cut EDM on ceramic particles reinforced Al-metal matrix composites – A review

Abstract Wire-cut Electrical discharge machining process [WEDM] is used in manufacturing industries to machine conductive and hard materials like metal matrix composites, ceramic composites and super alloys, which are having enormous applications in space craft, defense, transportation vehicles, micro systems, farm machinery etc. Aluminum based ceramic particle reinforced metal matrix materials is one of the key factor in producing composites, which enhances mechanical and thermal properties. These Composites (Al-MMCs) owing to having higher strength and stiffness are suitable for variety of engineering applications The current paper reviews the optimization of WEDM machining parameters, responses by deploying different techniques.

Synergetic strengthening effects on copper matrix induced by Al2O3 particle revealed from micro-scale mechanical deformation and microstructure evolutions

Abstract The micro-scale effect of Al 2 O 3 particle on the deformation behaviors of the copper matrix was investigated using nanoindentation. Moderate strengthening effects were produced by the Al 2 O 3 as indicated from the mechanical deformation evolutions. Specifically, the displacement recovery ratio and elastic work ratio is 6% and 9% higher for the Cu-5 wt% Al 2 O 3 (C5A) composite material compared with that of the pure copper (PC) material, respectively. While for the indentation hardness and indentation modulus, the increment is 36% and 75%, respectively. Notably, the moderate strengthening effects were quantitatively illuminated from the power law index m for the C5A indent (1.2) and PC indent (1.1–1.3). In addition, synergetic strengthening effects were proposed from the microstructure evolutions in the C5A composite material. Specifically, the increment in yield strength deduced from the grain refinement is 120 MPa, which is 67% higher than that of the Al 2 O 3 particle dispersion strengthening. The synergetic strengthening effects revealed from the microstructure evolutions are expected to provide new strengthening approaches for the ceramic particle reinforced metal matrix composite materials.

Geometrically nonlinear analysis of elastoplastic behavior of functionally graded shells

A geometrically nonlinear analysis of elastoplastic ceramic/metal functionally graded material (FGM) shells is investigated in this paper based on the first-order shear deformation theory. The elastoplastic behavior of the ceramic particle-reinforced metal matrix FGM shell is assumed to follow Ludwik hardening law. The elastoplastic material properties are assumed to vary smoothly through the thickness of the shells. The Mori–Tanaka model and self-consistent formulas of Suquet are employed to locally evaluate effective elastoplastic parameters of the ceramic/metal FGM composite. The homogenization formulation and numerical algorithms are implemented into ABAQUS/Standard via a user material subroutine (UMAT) developed to study the FG shells in large displacements and rotations. With the aim of demonstrating the accuracy of the present method, current numerical results are compared to experimental and numerical ones considering geometrically nonlinear elastoplastic FGMs and show very good agreement. The overall robustness of the new developed solution taking into account both geometric and material nonlinearities is demonstrated through several non-trivial benchmark problems taken from the literature. The effect of the constituent distribution on the deflections is analyzed.

A micromechanics analysis of the material removal mechanisms in the cutting of ceramic particle reinforced metal matrix composites

ABSTRACTIn previous investigations on the cutting of ceramic particle reinforced metal matrix composites using the finite element (FE) method, the particles are usually considered to be rigid. This is inconsistent with the actual situation and thus makes the FE predictions less practical. This paper proposes a micromechanics model to investigate the material removal mechanisms by considering the elasticity and fracture of the particles. It was found that the interaction position of a particle relative to the cutting edge greatly influences the particle and matrix fracture, particle-matrix debonding, surface integrity and cutting forces. There are two particle cracking mechanisms. One is caused by the direct contact of the cutting edge with the particle, and the other is due to the indirect tool-particle interaction through matrix. When the cutting path is below a particle, a smooth surface without subsurface damage can be achieved. When it is passing through a particle, particle fracture mostly occurs. If it is above a particle, subsurface damage is dominated by particle-matrix debonding. Cutting force peaks once the cutting edge is in contact with a particle and the cutting edge is easier to be damaged when the tool is passing through the upper part of the particle.

Numerical analysis of the mechanical behavior of ZTAp/Fe composites

Composites are complex and inhomogeneous. Various factors of microstructure will affect their mechanical behaviors. Based on a systematic numerical analysis, we present a coupling effect of the volume fraction of reinforced particles and the particle-matrix interface properties on the mechanical properties of ZTAp/Fe composites. We find that for yield limit and peak stress, the particle-matrix interface properties show a dominant impact while for the critical strain the particle volume fraction is the main factor. A combined effect of the particle volume fraction and the interface properties is found on the elastic modulus. The von Mises stress distributions are investigated and the results show that the particles clustered in the direction perpendicular to tensile load have larger debonding potential. In addition, the probability of particle cracking and the number of interface debonding are investigated to analyze the damage mechanism of the composites. We find that strong bonded interface can withstand more extra stress and protect the particle from cracking. The interface debonding rate becomes smooth after some critical value as the strain increases continuously due to a steady crack propagation after crack initiation along the interface line. This paper provides a guidance towards the design of advanced ceramic particle reinforced metal matrix composite materials.

Effect of SiCp volume fraction on the microstructure and tensile properties of SiCp/2024 Al-based composites prepared by powder thixoforming

Abstract

Fracture Mechanics Characterization of Sintered 30 Vol.-% Al<sub>2</sub>O<sub>3</sub>/TRIP Steel Composites Using SENB Miniature Samples

Ceramic particle reinforced metal matrix composites (PRMMCs) combine the strength and brittleness of ceramics with the toughness of a metallic matrix. In order to use these materials in construction and operational design their fracture mechanical behavior must be evaluated. In this study, a 30 vol.-% Al2O3 reinforced austenitic TRIP steel processed by powder metallurgical technique was investigated using precracked miniature SENB-specimens in 3-point-bending. An elastic-plastic analysis by means of the J-integral method in combination with optical crack observation showed the materials ability of stable crack growth, i. e. R-curve behavior. In addition to the mechanical tests microstructural studies were performed, whereby particle debonding and fracture as well as martensitic phase transformation and crack bridging within the matrix were identified as fracture energy dissipating mechanisms.

Laser surface forming of AlCoCrCuFeNi particle reinforced AZ91D matrix composites

Abstract Traditionally, the laser melt injection (LMI) technique can only be used for forming ceramic particles reinforced metal matrix composites (MMCs) for enhancing surface properties of lightweight engineering materials. In this research, the LMI method was employed to form metal particles reinforced MMCs on AZ91D instead. This was viable because of the unique properties of the AlCoCrCuFeNi high-entropy alloy (HEA) metal particles used. The large difference in melting point between the HEA and the substrate material (AZ91D), and the limited reaction and the lack of fusion between the HEA and Mg have made it possible that a metal particles reinforced AZ91D composite material was produced. The reason of limited reaction was considered mainly due to the relatively high mixing enthalpy between the HEA constituent elements and Mg. Although there was some melting occurred at the particles surface with some solute segregation found in the vicinity close to the surface, intermetallic compounds were not observed. With regard to the wear resistance of the MMCs, it was found that when the volume fraction of the reinforcement phase, i.e. the HEA particles, reached about 0.4, the wear volume loss of the coating was only one-seventh of that of the substrate material.

Effective thermo-mechanical properties of aluminum–alumina composites using numerical approach

This study examines the effect of microstructural characteristics on the effective thermo-mechanical properties, i.e., elastic moduli, Poisson’s effect, and coefficient of thermal expansion (CTE), of ceramic particle-reinforced metal–matrix composites. Two-dimensional (2D) micro-structures for composites with 10% and 20% alumina volume contents dispersed in aluminum matrix are constructed from the micrograph images of the composite samples taken at various locations. A representative area element approximately of size 50μm×50μm is chosen to represent the microstructure of the composite. For each of the selected square regions, ceramic content and porosity are first determined in order to examine the validity of the represented microstructure. These microstructures are implemented in finite element (FE) in order to numerically characterize the effective thermo-mechanical properties of the composites. The alumina constituent is assumed to behave as linearly elastic solid, while the aluminum constituent is modeled as an elastic–plastic solid with material parameters varying with temperatures. The effect of loading directions, porosity, properties of the constituents, particle sizes, and thermal (residual) stresses developed during cooling from the sintering temperature to room temperature, on the overall thermo-mechanical properties of the composites are further discussed.

Numerical Simulation on the Oblique Penetration of Ceramic Particles Reinforced Metal Matrix Functional Gradient Armor

Ceramic particles reinforced metal matrix functional gradient armor is a terrific protective material for helicopter gunship armor to gain light weight and improve anti-penetration performance. However, the anti-penetration mechanism is still not understood. In view of this fact, this paper aims to investigate the penetration mechanism of functional gradient armor. LS-DYNA software is used to simulate the processes of armor-piercing projectile oblique penetrating an optimal ceramic particles reinforced metal matrix functional gradient armor. The armor’s geometry of the calculation model considered is a four-sides-fixed supported round plate whose side length is far longer than its thickness. The penetrator considered is a long rod projectile. The results show that: when the oblique angle is relatively small, the projectile will turn to the vertical direction, that is to say, the oblique angle will diminish during the oblique penetration, and this phenomenon will do harm to the anti-penetration performance of the armor; when the oblique angle increases to a certain degree, the oblique angle will be enlarged during the oblique penetration, and this phenomenon will be beneficial to the anti-penetration performance of the armor. The bigger the oblique angle is, the easier the ricochet phenomenon will become. When design armors, the oblique angles of 0~15 degree should be avoided, and the oblique angles greater than 35 degree are preferred.

Probabilistic response of heterogeneous particle reinforced metal matrix composites with particle size dependent strengthening

This paper presents an enhanced continuum model for a heterogeneous particle arrangement to simulate the variability in the size dependent strengthening of silicon carbide (SiC) ceramic particle reinforced metal matrix composites (MMCs). The model incorporates a size dependent “punched” zone around the particles that is the result of a local increase in dislocation density during thermal processing due to geometrically necessary dislocations generated by the mismatch in coefficients of thermal expansion of the particle and matrix. In this work, these zones are explicitly accounted for in finite element simulations of multiple realizations of representative heterogeneous composite microstructures consisting of randomly distributed particles in a metal matrix. This modeling approach is used to capture the probabilistic response of the material which is linked to stochastic variations in the local microstructure of the material. The model is then used to explore the effects of particle size and volume fraction on the variability of the inelastic deformation response of heterogeneous MMCs. It is shown that the variance of the composite response increases as the particle size decreases and as the volume fraction of reinforcing particles increases. It is also shown that the amount of strain localization in the matrix increases as the particle size decreases.