Volume Fraction Of Phase Research Articles

Carboxylated chitin nanowhiskers enhanced stabilization of Pickering and high internal phase Pickering emulsions

Pickering emulsions stabilized by the emulsifiers derived from biobased materials have been widely used in food related fields. In the current study, Pickering emulsions possessing internal phase volume fractions (ɸ) from 0.5 to 0.8 were successfully prepared by mechanical emulsification methods using carboxylated chitin nanowhiskers (C-ChNWs) as the emulsifiers. C-ChNWs suspensions obtained by ammonium persulfate (APS) oxidation showed high stability and possessed a Zeta potential of −48.9 mV. FTIR and XRD analyses indicated the α-chitin crystal structure could be maintained following APS oxidation. The C-ChNWs could form a three-dimensional network structure at the interface and endow the emulsion with high stability and viscoelastic features. Morphology results demonstrated these were oil-in-water emulsions. Moreover, the prepared high internal phase Pickering emulsions (HIPPEs; ɸ >0.74) showed good texture characteristics for high-resolution 3D printing. This work further validated the potential of nanochitin derived from biomass as an outstanding Pickering emulsion stabilizer.

Development of High Strength and High Thermal Conductivity Semi-Solid Magnesium Alloy by Thixomolding Process

This paper investigates the influence of Cu addition on the microstructure, mechanical properties, and thermal conductivity of a semi-solid Mg-10Zn alloy produced by Thixomolding process. Microstructure of the Mg-10Zn alloy consists of α-Mg matrix and Mg2Zn second phase. The formation of Cu3Zn phase was found after the addition of Cu particles. Besides, the volume fraction of solid phase decreased in the Mg-Zn/Cu alloy compared with that of binary Mg-Zn alloy. The yield strength of the alloy was enhanced from 157MPa to 188MPa after Cu addition at the sacrifice of a small amount of ductility. Thermal conductivity, on the other hand, were kept the same level of 115-117 (W/m·K) in the Mg-10Zn alloy and Mg-10Zn/Cu alloy. This work demonstrates the potential for developing Mg alloys with high strength and high thermal conductivity via proper alloy design using Thixomolding process.

A sensitivity analysis of twinning crystal plasticity finite element model using single crystal and poly crystal Zircaloy

The popularity of crystal plasticity finite element method (CPFEM) models is increasing due to their ability to predict the mechanical response of crystalline materials such as metals and metal alloys more accurately than traditional continuum mechanics models. This is since the crystal plasticity models consider the effect of atomic structure, microstructural morphology, and properties of individual grains. These CPFEM models use a large number of material parameters in order to capture the mesoscale physics which comes with the downside of the tedious calibration process. In this paper, a CPFEM code was developed to include the twinning induced grain reorientation and subsequent crystallographic slip for HPC material. The developed code is incorporated in a large-scale, parallelized nonlinear solver WARP3D. A sensitivity analysis with respect to 22 material parameters was then conducted using single crystal and polycrystal representative volume element (RVE) of Zircaloy material. Loading was applied along five different crystallographic orientations for single crystal RVE and along three directions namely, rolling (RD), transverse (TD), and normal (ND) direction for polycrystal RVE. Results obtained from the sensitivity analysis were used for the calibration of material parameters for Zircaloy. Finally, developed code along with calibrated material parameters was used to investigate the effect of the hydride phase formation in Zircaloy which is a typical case observed for nuclear applications. It was found that the volume fraction of the hydride phase has a significant impact on the mechanical properties of Zircaloy.

Tunable anti-plane wave bandgaps in 2D periodic hard-magnetic soft composites

In this paper, we present a theoretical model for the analysis of large magneto-deformation and the anti-plane shear wave bandgaps in 2D periodic two-phase hard magnetic soft composite structures subjected to magnetic stimuli. The constitutive behavior of the phases in the hard-magnetic soft composite is described using the incompressible Gent model. To solve the incremental anti-plane wave equations, the finite element method and the Floquet–Bloch theorem for periodic media are utilized. Using the developed framework, we numerically study the dependency of the bandgap width and their location on the direction and magnitude of the applied magnetic flux density vector, material parameter contrasts, and geometry and volume fraction of the inclusion phase. The numerical results reveal that significant tunability of the bandgap is achieved when the applied magnetic flux density direction is along the residual magnetic flux density direction. Also, it is seen that the geometry of the inclusion has significant effect on the bandgap width. The crucial inferences from the present investigation can find their potential use in the design and manufacturing of futuristic smart soft wave devices with tunable band structures.

Friction stir processing: An effective thermo-mechanical processing technique for carbon steels

This review paper deals with the detailed study of published research work on FSW/FSP of different types of steels and post processing such as heat treatment effects on additively manufactured steel beads. In this context, it comprises of post processing effects on steel beads fabricated by additive manufacturing technique that includes different techniques like selective laser melting (SLM), Laser-TIG (Tungsten inert gas), Metal inert gas welding, etc. along with post processing techniques such as hot iso-static pressing (HIP), conventional heat treatment (HT), post weld heat treatment (PWHT), etc. Also, it consists of the pros and cons of FSW/ FSP, especially on low and medium carbon steels. Moreover, this paper is mainly related to the effects of friction stir welding/ processing on the evolution of microstructure, weld morphology, and temperature gradients in the processed region. In addition, there are detailed analyses of tool selection, effect of weld pitch ratio, effect of carbon content (Wt. %), and hard phase volume fraction on yield strength i.e. carbide distribution in the FSP low and medium carbon steels, and their correlation with the mechanical responses as well as crystallographic orientation relationship. Finally, based on published research, gaps are highlighted and presented as future scope of research work.

Morphology evolution and agglomeration mechanism of Fe5Si3 precipitated phase after Fe[sbnd]Si microalloying and its effect on the properties of brasses

The regeneration of scrap brass is affected by the impurity elements in raw materials. It is of practical significance to clarify the interaction of trace elements in brass melt for efficient recovery of scrap brass. The effect of FeSi microalloying on microstructure evolution and properties of as-cast H62 brass was investigated in the present study. The experimental results indicated that the microstructure of H62 brass containing 0.4 wt% Fe changed obviously after the introduction of silicon element. The volume fraction of Fe-rich phase increased with the increase of Si content, and the introduction of Si intensified the agglomeration behavior of Fe-rich phase. The thermodynamic analysis indicated that the silicon showed strong reactivity and bonding ability, and theoretical calculation suggested that silicon preferentially bonded with iron in melt to form new atomic clusters. The introduction of silicon also changed the morphology of the precipitated phase. The influence of silicon addition on the morphology evolution of FeSi precipitated phase was studied. The above reasons should be responsible for the microstructure evolution of as-cast brass. In addition, the mechanical properties and electrical conductivity of the microalloyed brass were tested. This study provides a new insight into the regulation of microalloying elements in regenerated brass.

Effect of nickel to cobalt ratio on mechanical properties of tungsten heavy alloys

The present study investigates the effect of Ni and Co on the mechanical properties of the W-Ni-Co alloy system. The alloys, based on 90 % W with varying Ni: Co ratios of 6:4, 7:3 and 8:2 (90W-6Ni-4Co, 90W-7Ni-3Co and 90W-8Ni-2Co) were processed through liquid phase sintering followed by a cyclic heat treatment (6 cycles). Thermomechanical treatment was carried out to improve strength and toughness levels. Quantitative metallography was employed to extract microstructural parameters including the volume fraction of the matrix phase, tungsten particle size, precipitate volume fraction and the contiguity of the W particles. The microstructural details at a finer scale were studied using scanning and transmission electron microscopy. Mechanical properties, such as tensile strength, elongation, hardness and impact toughness were also evaluated. The study shows that increasing the Ni: Co ratio decreases the precipitation of W in the matrix, which affects the mechanical behaviour of the alloys. The alloys having 7:3 and 8:2 Ni to Co ratio were additionally processed with an increased number of cycles (8 cycles) in the cyclic heat treatment to enhance the precipitation of fine W particles in the matrix. Since the alloy 6:4 showed brittle behaviour, it was not included for 8 cycles heat treatment study. The alloy with Ni to Co ratio of 8:2 resulted in superior combination of mechanical properties.

Investigation and production of non-cytotoxic TixNbxSn (x = 5,10,15,20) alloys by high-energy mechanical milling with antibacterial activity

In this research, TixNbxSn (x = 5, 10, 15, 20 wt%) alloys were produced by high-energy mechanical alloying, and their potential applications as biomaterial were investigated through the microstructural characterizations (via XRD, SEM, and EDS analyses), mechanical tests (via hardness and elastic modulus tests), and biological studies (via antibacterial and cytotoxic tests). The alloying studies were carried out at room temperature in a high-energy ball milling for 8 h followed by a consolidation using a uniaxial pressing and 2 h pressureless sintering at 1150 °C. The XRD and EDS analyses showed that α-Ti, β-Ti, and TiC phases were present in the microstructure after sintering at high-temperature. Hardness tests revealed a wide range of values between 384 and 723 HV depending on the alloy compositions. That is, the volume fraction of TiC phase formed during processing and the ratio of α-Ti/β-Ti phases appear to control the hardness of the alloys. The elastic modulus was determined ranging from 70 to 103 GPa as a function of compositions with Ti15Nb15Sn alloy having the closest elastic modulus to the bone. The biological investigations revealed that TiNbSn alloys exhibited antibacterial properties against Staphylococcus aureus (S. aureus) and were not cytotoxic to healthy cells, regardless of their compositions. Furthermore, the findings indicated that when the cells were subjected to various dilutions of alloy extracts, there was a noticeable enhancement in both cell proliferation and viability. These findings have the potential to pave the way for novel approaches in the creation of TiNbSn alloys as biomaterials.

Effect of the Reinforcing Particle Introduction Method on the Tribomechanical Properties of Sintered Al-Sn-Fe Alloys

The present paper reports the results of the comparative study of mechanical properties of sintered disperse-strengthened Al–40Sn alloy depending on the method of reinforcing particle introduction. The study is performed on two mixtures of aluminum and tin powders: one is admixed with 5.5–14.6 wt% of pure iron powder and the other contains the same amount of iron, but as a component of aluminide Al3Fe powders. The volume fraction of tin remains unchanged in all mixtures, being equal to 20%, and the concentration of hard particles increases due to a decrease in the volume fraction of the aluminum phase. Green compacts are sintered in the vacuum furnace at a temperature above the melting point of aluminum. The sintered material is a composite containing three phases: α-Al, β-Sn, and Al3Fe, in which the tin volume fraction is constant. Testing of the sintered composites for compression shows that the addition of finished Al3Fe particles has a more beneficial effect on their mechanical properties as compared to the addition of pure iron powders. In the latter case, aluminides are formed during sintering. The ultimate strength of composites reaches 180 MPa. Mechanisms of sintering of composites and the related structure and mechanical properties are discussed.

Enhancing the Strength and Toughness of A356.2-0.15Fe Aluminum Alloy by Trace Mn and Mg Co-Addition

In the present work, microalloying is put forward to improve the microstructure and tensile properties of A356.2-0.15Fe (wt.%) alloy by the co-addition of trace Mn and Mg. A suitable Mn/Fe mass ratio of 0.5 is obtained for alloys with 0.15Fe. The yield strength, ultimate tensile strength, and elongation of the A356.2-0.15Fe alloy with an Mn/Fe ratio of 0.5 and containing 0.42 wt.% Mg is 179 MPa, 286 MPa, and 9.1%, respectively, which is acceptable for automotive wheel hub applications. Optical microscopy (OM), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and electron-probe microanalyzer (EPMA) methods are used to characterize the microstructure of the alloys. The results indicate that Mn addition promotes the transformation of the acicular β-Al5FeSi phase to the block-shaped α-Al(Fe, Mn)Si phase. The ratio of length/width of the Fe-rich phase in the alloy is reduced by 78.8% with an Mn/Fe ratio of 0.5 and containing 0.35 wt.% Mg, compared with that of the alloy without Mn addition and containing 0.35 wt.% Mg. The addition of Mg reduces the secondary dendrite arm spacing (SDAS) from 26.1 μm to 20.9 μm. The volume fraction of the precipitated Mg2Si phase in the alloy containing 0.42 wt.% Mg increases by 60% compared with that in the alloy containing 0.35 wt.% Mg. The morphology transformation of the Fe-rich phase, the reduction of SDAS, and the increase in volume fraction of precipitated Mg2Si phase comprehensively contribute to the improvement of A356.2-0.15Fe alloy. The microstructure evolution mechanism and the effect of microstructure on tensile properties are analyzed and discussed.

Flow Field and Gas Field Distribution of Non-Submerged Cavitation Water Jet Based on Dual-Nozzle with Concentric Configuration

Cavitation water jet peening is an efficient and green surface treatment technology. The dual-nozzle can realize a cavitation water jet in air (non-submerged condition), which can be used for the surface treatment of large structures. The flow field characteristics of the dual-nozzle determine the cavitation effect. In this paper, the simulation of a cavitation water jet in air is carried out using Fluent software. The flow field characteristics containing velocity distribution, impact pressure, and gas phase volume fraction distribution are studied in detail. Furthermore, the effects of the nozzle structure parameters and incidence pressure on flow field characteristics are discussed. It was found that the structure parameters of the inner nozzle have a great influence on the flow field characteristics. Setting a contraction segment and expansion segment can improve the impact pressure and increase the intensity of the cavitation jet. Increasing the throat diameter and incidence pressure of the internal nozzle is also beneficial to improve the impact pressure and cavitation intensity. In order to assure a good cavitation effect, nozzle optimization should be performed. This study has guiding significance for the design of the dual-nozzle for a non-submerged cavitation water jet.

Numerical study of the effective thermal conductivity of 2-phase magnesium alloys containing solid solution atoms using lattice Monte-Carlo

The assessment of thermal conductivity in alloy plays a crucial role in ensuring their stability and performance in thermal applications. This paper specifically focuses on simulating the thermal conductivity of complex microstructures, which involve solid solution atoms and second phases. The lattice Monte Carlo (LMC) method is employed to examine the effective thermal conductivity of the Mg-(Ce, La) model alloy. The results obtained from numerical simulation are compared to experimental data, demonstrating a good agreement between them. Additionally, the study establishes a correlation between the content of solid solution atoms and thermal resistance through rj,α = A/(1-2x). Furthermore, the impact of various factors, such as volume fraction (fβ), size (Z), and morphology (F‾) of the second phase on the effective thermal conductivity, is thoroughly investigated and summarized. Overall, this research contributes to a better understanding the thermal conductivity behavior in complex alloy microstructures.

Numerical study on circumferential nonuniform characteristics of flow and heat transfer on double-side heating once-through steam generator with helical tubes

In this paper, double-side heating once-through steam generator with helical tubes as the prototype to establish its two-fluid Euler numerical model and verified through the Becker experiment. The results show that the two-phase fluid in the crescent-shaped passage moves spirally, and the two-phase flow velocity fluctuates along the Z-axis with a slip ratio greater than 1.0. The spiral motion results in greater centrifugal strength of the vapor phase than the liquid phase, the high centrifugal strength of the vapor phase results in a higher vapor phase volume fraction on the outer wall, which makes the position of the beginning of dryout and the position of the total dryout of the outer wall is advanced. The liquid phase volume fraction is highest on the narrow side inner wall and lowest on the wide side inner wall, so the inner wall dryout appears first and total dryout last. The circumferential non-uniformity results in a spiral band of vapor content and temperature distribution.

Effect of post weld heat treatment on weld metal microstructure and hardness of HFCA-TIG welded ASTM-B670 high temperature alloy joints

In this investigation, the effect of post weld heat treatment (PWHT) conditions on weld metal (WM) microstructure and hardness of ASTM B670 alloy joints are studied for gas turbine engine applications. This high temperature alloy was joined using high frequency compressed arc TIG (HFCA-TIG) welding process. The precipitation hardening was performed on ASTM-B670 alloy joints directly after welding (DPH); after solutionizing the welds at 980 °C (980ST+PH) and at 1065 °C (1065ST+PH). The WM of ASTM-B670 alloy showed better response to PWHT in minimizing the Laves phases and enhancing the WM hardness of joints. The DPH, 980ST+PH and 1065ST+PH joints showed 55.63%, 58.80% and 64.08% enhancement in hardness of WM compared to as welded (AW) joints owing to the precipitation of hardening phases after PWHT. The 1065ST+PH joints revealed higher hardness of WM than DPH and 980ST+PH joints It is attributed to the complete dissolution of Laves phases in WM causing more Nb available for precipitation hardening of WM. Nevertheless, the PM hardness of 1065ST+PH joints are lower than 980ST+PH joints owing to the severe grain growth. The HFCA-TIG welds showed volume fraction of Laves phase up to 5.10% in WM which is 80.38% and 36.25% lower than constant current TIG (CC-TIG) and pulsed current TIG (PC-TIG) welds. It is attributed to magnetic compression and high frequency pulsation of arc which minimizes input of heat in welding and offers greater refinement of WM.

Compressive property and energy absorption characteristic of interconnected porous Mg-Zn-Y alloys with adjusting Y addition

In this study, interconnected porous Mg-2Zn-xY alloys with different phase compositions were prepared by various Y additions (x = 0.4, 3, and 6 wt. %) to adjust the compressive properties and energy absorption characteristics. Several characterization methods were then applied to identify the microstructure of the porous Mg-Zn-Y and describe the details of the second phase. Compressive tests were performed at room temperature (RT), 200°C, and 300°C to study the impact of the Y addition and testing temperature on the compressive properties of the porous Mg-Zn-Y. The experimental results showed that a high Y content promotes a microstructure refinement and increases the volume fraction of the second phase. When the Y content increases, different Mg-Zn-Y ternary phases appear: I-phase (Mg3Zn6Y), W-phase (Mg3Zn3Y2), and LPSO phase (Mg12ZnY). When the Y content ranges between 0.4% and 6%, the compressive strength increases from 6.30 MPa to 9.23 MPa, and the energy absorption capacity increases from 7.33 MJ/m3 to 10.97 MJ/m3 at RT, which is mainly attributed to the phase composition and volume fraction of the second phase. However, the average energy absorption efficiency is independent of the Y content. In addition, the compressive deformation behaviors of the porous Mg-Zn-Y are altered by the testing temperature. The compressive strength and energy absorption capacity of the porous Mg-Zn-Y decrease due to the softening effect of the high temperature on the struts. The deformation behaviors at different temperatures are finally observed to reflect the failure mechanisms of the struts.

A comparative study on emulsification in the presence of a nanoclay (Pickering emulsion) or a surfactant using high intensity mixing

The study explored the potential of using a nanoclay, Laponite RD, as a stabilizing agent in comparison to a surfactant, Tergitol TMN6, at dispersed phase volume fractions of 10–50% vol. An ultrasonicator was employed as an energy intensive device; covering a specific power input range of ∼ 36–52 W kg− 1. In both cases, final dispersions obtained could be considered stable over the period of ageing tests for 3 months as comparable drop size distributions were obtained although there were some differences in the rheology at the highest dispersed phase concentration. Whilst surfactant stabilized emulsions were of Newtonian behavior, Pickering emulsions stabilized with the nanoclay exhibited non-Newtonian behavior, which may be a desirable feature of the final product- certainly one that requires attention in design and scale up. Kinetics of breakup studied through the evolution of the Sauter mean diameter prior to reaching an equilibrium value on the basis of energy density have shown the breakup process being faster with the Pickering emulsions although the equilibrium drop diameters were larger. Overall, with emulsions stabilized using a surfactant, Sauter mean drop diameters could be as low as 240 nm, regardless of the dispersed phase volume fraction, drop sizes were larger with Pickering emulsions which depended on the dispersed phase concentration.

Simulation of reaction initiation in powder compacting from the surface with composite formation in equivalent reaction cell

In the present work, we propose a new variant of the model of the composite synthesis under surface heating. We believe that the formation of the composition occurs at the level of reaction cell. The diffusion-controlled process of reduction of one material by another from an oxide is described in the framework of the problem with moving boundaries. It is assumed that the formation of the matrix composition is carried out by the diffusion mechanism. From the position of interfaces, we find the relative volume fractions of oxide phases and the fraction of volume occupied by the matrix. The averaging method of the analysis results at the reaction cell level makes it possible to use these data at the macroscopic level. Volume fractions of phases and average matrix composition (obtained by averaging over the area occupied by the matrix) provide values reflecting the composition of the composite at the macro level. The problem is solved numerically in dimensionless formulation. Dimensionless complexes of physical quantities are distinguished. The estimation of these parameters is performed. The conditions of correctness of the proposed approach are established from comparison of temporal and spatial scales of thermal and diffusion phenomena. A numerical algorithm for the joint solution of macro- and mesolevel problems has been developed. The proposed algorithm makes possible the investigation of the dynamics of composition changes at all points. The model is supplemented by the calculation of stresses and strains from the data on composition and temperature changes in reaction cells. Averaged values of stresses are transferred to macro level.

Recent <i>In Situ</i> Experimental and Theoretical Advances in Severe Plastic Deformations, Strain-Induced Phase Transformations, and Microstructure Evolution under High Pressure

Severe plastic deformations (SPD) under high pressure, mostly by high-pressure torsion, are employed for producing nanostructured materials and stable or metastable high-pressure phases. However, they were studied postmortem after pressure release. Here, we review recent in situ experimental and theoretical studies of coupled SPD, strain-induced phase transformations (PTs), and microstructure evolution under high pressure obtained under compression in diamond anvil cell or compression and torsion in rotational diamond anvil cell. The utilization of x-ray diffraction with synchrotron radiation allows one to determine the radial distribution of volume fraction of phases, pressure, dislocation density, and crystallite size in each phase and find the main laws of their evolution and interaction. Coupling with the finite element simulations of the sample behavior allows the determination of fields of all components of the stress and plastic strain tensors and volume fraction of high-pressure phase and provides a better understanding of ways to control occurring processes. Atomistic, nanoscale and scale-free phase-field simulations allow elucidation of the main physical mechanisms of the plastic strain-induced drastic reduction in phase transformation pressure (by one to two orders of magnitude), the appearance of new phases, and strain-controlled PT kinetics in comparison with hydrostatic loading. Combining in situ experiments with multiscale theory potentially leads to the formulation of methods to control strain-induced PT and microstructure evolution and designing economic synthetic paths for the defect-induced synthesis of desired high-pressure phases, nanostructures, and nanocomposites.

Water-in-oil emulsion drop-wall impact: Effect of viscosity and water particles on slip length over an oleophilic surface

The study is focused on the numerical simulation of the boundary slip of a water-in-oil (W/O) emulsion along an oleophilic surface in a 2D axisymmetric formulation of the Navier–Stokes equations for an incompressible laminar flow. Drops of emulsions with a volume fraction of the dispersed phase of 0.04–0.34 collide with a smooth glass wall at initial velocities of 1.2–3.6 m/s; the motion of the interface between the liquid and gas phases is resolved by the level set method. The influence of the wall wettability by oily liquids is demonstrated by varying the static contact angle up to 0.5° and by considering the dynamic one as a function of the empirically measured contact line velocity of the liquid drop according to Tanner's law. Numerical simulation of emulsion drop spreading dynamics reveals that the boundary slip of a heterogeneous liquid along a smooth oleophilic wall is different from that of a homogeneous. The temporal changes in the average viscous stress allowed the illustration of the interrelated effects of emulsion viscosity and the presence of disperse phase particles on the boundary slip of a heterogeneous liquid and its motion in the viscous boundary layer. The analytical expression evaluating the slip length for an arbitrary W/O emulsion was derived using the effective properties of the liquid. In testing the expression, the values of the maximum spreading factor of drops of an arbitrary W/O emulsion predicted by numerical simulation correspond to those determined from experiments at a moderate error of 7.4%.

WITHDRAWN: Microstructural analysis and mechanical properties of a dissimilar material of AISI 4130 steel substrate coated with Stellite 6 manufactured by transferred ARC plasma welding (PTA)

This work evaluated the effect of varying PTA welding parameters on dilution: microstructure, microhardness, hardness and wear resistance. Two medium-carbon, low-alloy, high-strength alloy steel tubes, AISI 4130, were coated with CoCrWC cobalt alloy (Stellite 6) by powder-fed transferred arc plasma (PTA) welding process. Two different conditions were analyzed, varying the welding current, being 90A for condition 1 and 109A for condition (2). Appropriate specimens were removed for carrying out the metallographic tests, and microhardness, hardness and resistance to wear values were analyzed. abrasive wear. The samples were metallographically prepared for evaluation of the weld bead and the coating phases, through analyzes using SEM, EDS and X-ray diffraction (XRD). Rubber wheel abrasion tests were carried out following the ASTM G65 standard. It was observed that condition (2), with the lowest hardness value, highest dilution and a lowest volumetric fraction of carbides, presented a higher rate of wear, with its coating worn to the point of exposing the base metal after the test, when compared to condition (1), which presents a higher volume fraction of carbide phases, lower level of dilution and higher hardness.