Sulfuric acids are commonly used in acidic cleaning processes of steel surfaces. However, steels have low corrosion resistance to hot, acidic environments. The aim of this article is to investigate the effects of boride coating on the corrosion behavior of AISI 8620 steel in a hot H2SO4 acid solution. The boriding process was carried out with Baybora-1, a novel boriding powder. Using the powder pack boriding method at a temperature of 900 degrees C for 2 and 6 h. The thickness of the boride layer formed on the steel surface was measured by scanning electron microscopy (SEM) analysis. The corrosion behavior of the samples in a hot H2SO4 acid solution was determined using the ASTM G31-72 standard. The results showed that pitting-type corrosion occurred when nonborided AISI 8620 steel was exposed to hot sulfuric acid solutions, but the boriding time increased the corrosion resistance of AISI 8620 steel to hot sulfuric acid solutions. It was found that the corrosion resistance of the steel increased 18-fold thanks to the boride coating, which was formed on the surface of AISI 8620 steel by the boriding process. Boriding could be an alternative application to increase the corrosion resistance of steels.
Against the backdrop of the “dual carbon” targets, optimizing blast furnace (BF) ironmaking processes is pivotal for realizing low-carbon smelting. Grounded in fundamental ironmaking principles, this study systematically investigates the 2023 production data of 24 large BFs in China (effective volume > 4000 m 3 ) to uncover the intrinsic relationships between the oxygen consumption and its key influencing factors. Practical methods for reducing oxygen consumption are proposed and demonstrated through a case study of a Chinese large BF, whose fuel consumption has been successfully reduced. Analysis reveals that for large BFs over 4000 m 3 , oxygen consumption reduction of 5 m 3 /t yields corresponding reductions of 4.2 kg/t in fuel ratio and 1.6 kg/t in process energy consumption. Both theoretical analysis and operational verification confirm that reducing oxygen consumption is a crucial pathway toward low-carbon and high-efficiency BF smelting.
Non-metallic inclusions severely impair the quality of ultra-low carbon steel continuous casting slabs, with control efficiency varying across casting stages due to differing molten steel flow, temperature stability and process conditions. Head slabs face inclusion aggregation from unstable initial flow, transition slabs suffer inclusion increases from heat-switching fluctuations, and normal slabs need precise control for consistent cleanliness despite stable conditions. Leveraging the positive charge of inclusions like Al2O3, pulsed electric current (PEC) enables directional migration, aggregation inhibition and efficient removal of inclusions, with proven industrial effects in molten steel purification and SEN anti-clogging. Industrial comparative experiments on a twin-strand caster (comparative/experimental strand without/with PEC) for automotive IF steel were conducted, testing inclusion density and size distribution of the three slab types via ASPEX analyzer. Results show PEC effectively reduces inclusion density (head slab: 0.88 -> 0.84 mm(2), normal slab: 0.69 -> 0.65 mm(2), transition slab: 0.76 -> 0.71 per mm(2)) and optimizes size distribution: fine inclusions (<= 5 mu m) rise significantly, medium/large ones (>5 mu m) drop, and >20 mu m inclusions in normal slabs are eliminated. This study uncovers PEC's regulation mechanism, verifies its universal purification effect, and provides a reliable technical solution for high-quality ultra-low carbon steel production.
The prediction of phosphorus content in molten steel at the end of converter is of great significance to control the quality of steel and reduce the production cost. In order to achieve accurate prediction, aiming at the problem of small sample size and poor stability of single model, this paper proposed a prediction method of terminal phosphorus content combining Dung beetle optimization (DBO) algorithm and ensemble transfer learning strategy(EL-TL). Firstly, the improved Dung Beetle optimization algorithm (IDBO) was improved to optimize the hyperparameters of the Multi-layer Perceptron (MLP). Secondly, the transfer learning strategy was introduced and the multi-kernel maximum mean difference was improved to solve the problem of insufficient prediction accuracy of small samples. Finally, the ensemble learning strategy and adaptive weight improvement were introduced to further solve the problem of insufficient stability and easy overfitting of a single model. The ablation experiment verifies that the proposed method achieves 85% hit rate within the error range of plus or minus 0.002%, which can provide guidance for practical production.
This work is devoted to experimental modeling of metal melt solidification processes under the influence of electromagnetic fields of various topologies. The main objective of the work is to develop a method for improving solidification parameters by changing the topology of the electromagnetic field without changing its amplitude and frequency, and therefore energy consumption. Both classical metallurgical modes of travelling and rotating magnetic fields and more complex combinations of spiral and torsional topologies are considered. Velocity fields of flows arising in the liquid phase under the influence of electromagnetic fields of given topologies are obtained using a low-melting gallium-based alloy and ultrasonic Doppler velocimetry technique. Macroscale solidification characteristics, namely, the velocity of the solidification front and the heterogeneity of its shape, are obtained for all modes. It has been shown that changing the topology of magnetic fields can increase the homogeneity of the solidification front by an order of magnitude. Specifically, the highest ratio of the time-averaged solidification front heterogeneity parameter between the modes reached 11.5 times (29.9 mm for the classical magnetic field distribution and 2.6 mm for the best magnetic field topology option we suggest). The results obtained for the gallium eutectic were confirmed for an aluminum alloy. The use of stirring in the torsional magnetic field mode during the solidification process increased the proportion of the fine-grained solid fraction by 30 percents.
Hot-stamped 7xxx aluminum components usually exhibited poor mechanical uniformity due to microstructural inhomogeneity and high quench sensitivity. In this work, an industrially scaled modified alloy was developed by substituting Cr with Zr, increasing Zn/Mg ratio and reducing the contents of Mn, Cu, Fe and Si, combined with three-stages homogenization. This resulted in a homogeneous microstructure and low quench sensitivity. In addition, the thermal-buffer forming temperature of the alloy was determined using DSC analysis, tensile tests, and phase transformation modeling. The results showed that the optimal forming temperature was 500 degrees C, which preserved solute supersaturation during transfer. After T6 aging, the ultimate tensile strength, yield strength and elongation of the components reached over 540 MPa, 470 MPa, and 14%, respectively. Moreover, the mechanical properties were highly uniform: the hardness variation was within 3 HV, strength dispersion was less than 13.5%, and elongation difference was no more than 1%, satisfying the safety requirements for automotive structural components.
To improve the uniformity and purity of molten steel, a multi-physical model was used to study the influence of flow control devices on molten steel flow, heat transfer and inclusion removal in a seven-strand dual-nozzle tundish. The results show that the simulated molten steel flow and residence time distribution (RTD) curve are basically consistent with the physical simulation experiment results. After adopting the U-shaped baffle and the optimized turbulence inhibitor (TI), the average residence time reaches 248.0 s, the dead zone volume is reduced by 36.63%, the response time and residence time of the middle strand are increased by 24.0 s and 152.0 s respectively, and the standard deviation of the average residence time is reduced from 23.25 of the prototype model to 15.47 at a casting speed of 3.0 m/min. Meanwhile, the maximum temperature drop is reduced from 38.7 K to 23.7 K, and the molten steel temperature difference between each strand is reduced from 4.5 K to 1.1 K, a decrease of 75%. The removal rate of inclusions with diameter of 100 mu m is about 95%, and the consistency between each strand is obviously enhanced.
This study investigates the mechanical properties and microstructural evolution of Cu-1.43Ni-1.05Co-0.54Si and Cu-1.41Ni-0.98Co-0.52Si-0.05Ti alloys during aging. The addition of Ti significantly enhances the mechanical performance by effectively suppressing the growth and coarsening of (Co, Ni) 2 Si precipitates and maintaining a high dislocation density under identical aging conditions. First-principles calculations reveal that this enhancement originates from the preferential segregation of Ti atoms at the (Co, Ni) 2 Si/Cu matrix interface, which considerably increases the interfacial adhesion energy and thus effectively impedes precipitate coarsening.
The growing trends in manufacturing industries have led to the development of advanced materials with high strength, low weight, and enhanced mechanical and chemical properties. However, Machining of these newly developed materials has become prime issue for manufacturers. Furthermore, The increasing demand of miniaturized products has intensified the need for manufacturing at micro and nano levels. Industries such as automobiles, electronics, aerospace, and nuclear reactors require components with higher accuracy and precision. To address these requirments, a closed-loop feedback control system was designed and developed for applications in non-conventional machining processes such as ultrasonic machining (USM), electro discharge machining (EDM), electro chemical machining (ECM), with minor modifications. The system feasibility was validated using an electro-deposition process. The developed system uses voltage as an input signal to estimate the gap between the electrode and workpiece through a derived mathematical relationship. The deviation from the predefined gap is converted into control pulses to drive a stepper motor for precise tool positioning. Experimental results show smooth motor operation at 313 Hz with a minimum threshold voltage of 2.7 V. Voltage errors of 0.012 V and 0.004 V were obtained for 85 and 150 samples, respectively, indicating improved accuracy with increased sampling, although the response time increased to approximately 2 s. The system achieved positional control within 0-5 mm using a lead screw (pitch 1 mm) with a basic length unit of 0.005 mm. The total fabrication cost was approximately Indian Rupee 5800, demonstrating the cost-effectiveness of the proposed system. Overall, the developed low-cost feedback control system exhibits reliable performance and can be effectively adapted for precision control in modern non-conventional machining processes.
Against the backdrop of global climate change mitigation efforts, electric arc furnace short-process steelmaking has become a core direction for the green upgrading of the steel industry due to its potential for energy conservation and emissions reduction. However, electric arc furnace steelmaking with high scrap steel ratios generally faces challenges in dephosphorization, attributable to the inherent characteristics of raw materials, process parameters, and equipment design. This poses a conflict with the low phosphorus content requirements for high-quality steel, thus hindering the development of low-carbon, green, high-quality steel. Based on the ion-molecule coexistence theory, this study establishes a thermodynamic model and carries out experimental studies under typical high scrap steel ratio conditions. It systematically examines the dephosphorization behavior of the CaO-SiO2-FeO-MgO-P2O5 slag system at 1873 K, quantifies the influence of slag composition on the phosphorus distribution ratio, and reveals the mechanism by which the scrap steel ratio promotes dephosphorization through its effect on the phosphorus activity coefficient. Experimental results indicate that for highly efficient dephosphorization, the slag system's basicity should be controlled between 2.5 and 3, with FeO content ranging from 25% to 30%. Under these conditions, the phosphorus content in the final molten steel can reach 0.005-0.01%, achieving a dephosphorization rate as high as 93-97%. Further research revealed a synergistic equilibrium relationship between basicity and FeO: excessively high basicity weakens dephosphorization due to thermodynamic saturation and increased viscosity, while FeO exceeding critical levels exerts a negative effect through dilution and elevated P2O5 activity. The final slag system achieved a phosphorus distribution ratio of 4.17-4.61 and an apparent mass transfer coefficient of 1.94-2.43 cm(3)/s. These findings provide critical theoretical and parametric foundations for slag system design and process optimization in high-quality steel production within electric arc furnaces.
The straight grate induration process is widely used in iron ore pellet production because of its continuous operation, high automation level, and strong industrial adaptability. However, frequent fluctuations in ore sources, raw material prices, and operating conditions make it difficult to simultaneously ensure pellet quality and cost-effectiveness. To address this issue, this study develops a data-physics dual-driven optimization framework for coordinated ore blending and induration optimization. In this framework, pellet quality is predicted by a Bayesian-optimized Gradient Boosting Regression Tree (BO-GBRT) model, and process feasibility is ensured through theoretical blend calculation and engineering constraints. Industrial production data were first cleaned using the interquartile range and Isolation Forest methods, and key variables were screened through a multi-correlation feature selection strategy. To improve model reliability, RF, GBRT, XGBoost, and LightGBM were benchmarked under a 5-fold cross-validation scheme. The results showed that GBRT and XGBoost provided the best overall predictive capability, while GBRT exhibited more stable and balanced performance across six pellet quality indicators; therefore, GBRT was selected for further Bayesian optimization. The resulting BO-GBRT model served as a soft sensor, while theoretical blend calculation and engineering constraints were incorporated to ensure operational feasibility. Based on the surrogate model, NSGA-II was employed to obtain Pareto-optimal solutions for cost-quality trade-offs, and TOPSIS/VIKOR were used to rank candidate operating schemes. The optimized solution achieved stable production at a unit cost of 998 & YEN;/t while maintaining satisfactory pellet quality. The proposed framework provides a practical decision-support tool for straight-grate pellet production under dynamic raw-material and operating conditions.
This study systematically investigates the precipitation and evolution behaviors of TiC, ZrC, and YC2 carbides in FeCrAl alloys through heat treatments at 600, 900, and 1200 degrees C, combined with thermodynamic calculations, growth kinetics modeling, and dissolution simulations. The results show that the precipitation of the three carbides exhibits strong temperature dependence: TiC and ZrC are the dominant phases in the as-received alloy; after heat treatment at 600 and 900 degrees C, YC2 becomes the main precipitated phase; at 1200 degrees C, TiC and ZrC re-precipitate extensively, forming fine TiC nanoparticles and irregular ZrC-YC2 composite structures. Thermodynamic analysis indicates that all three carbides satisfy the liquid-phase precipitation conditions within the carbon range of 0.005-0.05 wt.%, among which YC2 shows the strongest precipitation tendency. Competitive stability calculations reveal that TiC exhibits the highest thermodynamic stability at elevated temperatures, followed by ZrC, whereas YC2 remains stable mainly at lower temperatures. Growth kinetics results show that carbide size increases with carbon content, with YC2 exhibiting the largest growth, followed by TiC, while ZrC grows the least. According to the LSW theoretical prediction, the coarsening of the three carbides is minimal within 600-1200 degrees C, and the sizes of TiC and YC2 remain nearly unchanged. Dissolution simulations further demonstrate a strong temperature sensitivity: at 1200 degrees C, the dissolution time of 5 mu m carbides is significantly reduced, with TiC, ZrC, and YC2 requiring 125.47, 233.47, and 229.40 s, respectively, whereas at 600 and 900 degrees C, the dissolution time increases sharply.
More in-depth studies on the gasification behavior and mechanism of coke by H2O are needed due toblast furnace (BF) hydrogen-rich smelting becomes a popular topic. This paper focuses on the gasificationdissolution loss experiment of coke by H2O . The results indicate that: As the H2O content increases, the cokesurface becomes noticeably rougher, the changes on coke surface can be divided into two situations. The peaks oncoke surface are consumed again and again, the coke surface is gradually eroded in this cycle. The degree ofunevenness on coke surface shows that the baseline of gasification reaction has been decreased as the reactionprogresses. After 60 minutes of gasification, the overall average of pores has expanded, and the distribution ofpores on coke surface is no longer uniform. The proportion of isotropic structure decreases with the prolongationof gasification dissolution loss time and temperature. Even in anisotropic structure, the proportions of eachstructure are changing, and this evolution may be the fundamental reason for the changes in macroscopicproperties of coke. In the infrared spectral curve, aromatic ring (C=C stretching vibration) and free hydroxylgroup (stretching vibration of O-H) have been discovered. The number of free hydroxyl group has decreased dueto the consumption of free hydroxyl group in the gasification reaction. High temperature promotes theseparation of free hydroxyl group from H2O , There are more media provided, which is the microscopic reason forthe intense gasification. The entire process of coke dissolution by H2O is summarized, the gasification dissolutionmechanism based on active sites is proposed to understand the behavior of coke. On active sites, the adsorptionof reactantsfirst occurs. The adsorption saturation of active sites is defined to clarify the adsorption anddesorption on active sites
The interface bonding strength of S32168/Q345R is affected by different process parameters as a composite plate of a pressure vessel. Previous research has focused on the influence of rolling parameters in governing both grain structure optimization and element diffusion on bonding strength but has not deeply explored the nonlinear relationship between rolling speed and interface bonding performance and the coupling effect of temperature and deformation heat on bonding properties. In this work, S32168/Q345R composite plates were prepared by hot rolling with different rolling speeds and reductions, and the microscopic experiments and mechanical properties of the composite plates after rolling were tested. The experimental results indicate that the bonding strength ranges from 390.9 to 548.6 MPa, which is much higher than the 210 MPa required by the international pressure vessel plate. This study shows that different rolling parameters act on the dynamic recrystallization and the heat diffusion affected by the deformation heat and deformation time so as to realize the microstructure optimization and performance optimization. In addition, the evolution of the interface microstructure is dominated by carbon migration: carbon loss on the Q345R side forms a ferrite decarburization layer, and Cr 23 C 6 and TiC 2 carbides are formed on the S32168 side. This research elucidates the mechanisms by which various rolling parameters govern bonding strength and explores the formation process of carbonized inclusions and decarburization layer thickness and the influence on the interface bonding strength.
This study investigates the impact of cooling rate on the morphology, size distribution, and precipitation characteristics of MnS and Al2O3-MnS inclusions in 20CrMnTi gear steel. Experiments were conducted using three cooling methods. Water-cooling conditions produced fine, dispersed MnS particles, while air-cooling conditions led to the formation of chain-like aggregates with rod or block shapes. In contrast, furnace-cooling conditions yielded irregularly shaped, dispersed MnS inclusions. The sizes of the inclusions were predominantly in the range of 2-5 mu m under water-cooling and air-cooling conditions, whereas they increased to 5-10 mu m under furnace-cooling conditions. The number of Al2O3-MnS inclusions was inversely proportional to the cooling rate. Thermodynamic analysis indicates that Al2O3 precipitates above the liquidus, while MnS forms at the end of solidification (solid fraction: 0.984). Growth kinetics reveal average MnS sizes of 2.3 mu m for water-cooling, 4.5 mu m for air-cooling, and 13.1 mu m for furnace-cooling, confirming that as the cooling rate decreases, the MnS size increases. The push-capture behavior is influenced by the precipitation temperature. The size of Al2O3 decreases, while the push-capture critical rate (nu cr) increases with higher cooling rates. When nu cr exceeds the coarsening rate, smaller Al2O3 particles are entrapped in the liquid phase, providing nucleation sites for MnS.
To address the center segregation issue of 75Cr1 high-carbon low-alloy tool steel produced through the domestic CSP process without electromagnetic stirring (EMS), this study systematically investigates the inhibition mechanism of the CSP process on center segregation by integrating multiscale and micro-characterization with thermodynamic calculations, fractal dimension analysis, and other methods. The results show that: slab bulging in the CSP process significantly enhances the driving force of molten steel flow and exacerbates the macrosegregation at the slab center; after process optimization, slab bulging is mitigated, leading to a substantial reduction in center macrosegregation. Meanwhile, columnar dendrites penetrate the center to form a transcrystalline structure with refined grains, where the secondary dendrite arm spacing ranges from 21 to 183 mu m and the permeability from the slab surface to the center is 0.1 to 5.1 mu m2. The cooling rate of the CSP process is nearly 15 times higher than that of the traditional process, ranging from 0.5 to 25 K/s. Electron Probe Microanalysis (EPMA) results demonstrate that C, Mn and Cr are enriched toward the center, C, Mn and Cr show similar segregation trends, while Si is uniformly distributed in the form of discrete spots. Thermodynamic calculations indicate that solute redistribution is concentrated at the solid-liquid interface; the equilibrium distribution coefficient of C is small and decreases with decreasing temperature, rendering it prone to segregation; the equilibrium distribution coefficients of Cr and Mn deviate further from 1 as temperature drops, resulting in intensified segregation; whereas that of Si approaches 1, leading to a low segregation tendency, which suggests that the CSP process exerts distinct segregation inhibition mechanisms for different elements. Calculations of fractal dimension and generalized entropy reveal that the self-similarity of the structure decreases from the slab edge to the center line, the negative entropy flow increases, the system entropy decreases, and the disorder degree of the solidification system is reduced. The findings of this study provide theoretical and empirical support for understanding the regulation mechanism of the CSP process on the center segregation of 75Cr1 steel.
To intensify the process of hydrogen reduction of iron oxide ore, an annular hydrogen shaft furnace (HSF) has recently been proposed to mitigate the formation of a central stagnant zone. In this work, the annular concept is thoroughly optimized with respect to both geometric design (alpha, the ratio between the inner and outer radii) and gas-feed strategy (beta, the fraction of gas injected through the inner wall) using an axisymmetric two-dimensional computational fluid dynamics model. The results show that under the operating conditions considered an annular HSF with alpha = 0.04-0.08 provides favorable furnace performance in terms of the final solid metallization degree. From a practical standpoint, moreover, the acceptable range of alpha can be extended up to 0.2, where the areal productivity of metallic iron increases by about 3.8%. As for dual-side gas injection, a relatively even gas distribution with beta = 0.4-0.6 significantly improves the in-furnace thermochemical state. With an increase of beta, however, the pressure at inner bustle pipe increases markedly. This issue of practical relevance can be effectively addressed by adopting dual-row injection at the inner wall. The combined results provide practical guidelines for the integrated design and operation of the annular HSF for fossil-free ironmaking.
The abstract has been revised, displayed as: "The effect and mechanism of isothermal homogenization heat treatment on the morphology and distribution of MnS inclusions in 46MnVS5 steel were systematically studied in this paper. By designing isothermal treatment experiments at different temperatures (950-1350 degrees C) and time (1-10 h), combined with OM, SEM and ASPEX automatic statistical analysis, the evolution law of MnS was revealed. The results show that under 3 h isothermal treatment, MnS undergoes the evolution sequence of "splitting-passivation-spindle-spheroidization" with increasing temperature. The spheroidization effect is optimal at 1250 degrees C, where the proportion of inclusions with aspect ratio below 3 exceeds 90%. At 1250 degrees C, the morphology of MnS evolved from elongated to short rod-like, spindle-shaped, and finally spherical with increasing holding time. After 3 h, splitting was largely complete, and the number density transitioned from increasing to decreasing, indicating a shift in dominant mechanism from fragmentation to coalescence and dissolution. Mechanism studies reveal that the evolution process is driven by Ostwald ripening and surface energy minimization, with mass transfer controlled by surface diffusion. Thermodynamic analysis further reveals that the rate-limiting element for Ostwald ripening shifts with temperature, transitioning from Mn at 1050 degrees C to S at 1250 degrees C. The optimal homogenization condition (1250 degrees C, 3 h) resulted in over 90% of MnS inclusions with aspect ratio <3, significantly improving morphological uniformity. The controlling element for Ostwald ripening shifted from Mn at 1050 degrees C to S at 1250 degrees C, providing new insight into inclusion engineering. These findings establish a theoretical foundation and practical process route for enhancing the properties of non-quenched and tempered steel.
In the process of top-blown converter steelmaking, the jet characteristics of the oxygen lance nozzle have a direct impact on the slag melting rate within the molten pool and the stirring effect of the molten steel, which influence steelmaking efficiency and product quality. In this research, a five-hole oxygen lance nozzle model suitable for 100-ton converters was established. Through numerical simulation, the effect of oxygen preheating temperature (300-900 K) on velocity decay, impact characteristics, and stirring performance of the five-hole oxygen lance jet under high-temperature conditions (1873 K) was analyzed. Results indicate that at high temperatures, increasing the oxygen preheating temperature significantly extends the length of the high-velocity jet region (jet velocity >= 500 m/s). However, this intensifies jet deflection and velocity decay, while also substantially shortening the length of the supersonic region. The optimal operating gun positions are 2.9 m for slag treatment and 2.5 m for conventional melting operations, corresponding to oxygen preheating temperatures of 800 and 600 K, respectively. Compared to the preheating temperature of 300 K, the 800 K oxygen jet increases the slag treatment area by 62.23% and reduces molten steel splashing by 76.44%. At a preheat temperature of 600 K, the effective impact area of the oxygen jet increases by 5.38%, the molten steel splatter rate decreases by 77.09%, and the mixing time increases by 68.18%. Notably, selecting an appropriate preheating temperature can effectively reduce splatter and enhance slag melting rate while also slightly improving smelting efficiency. Although mixing time significantly increases during this process, it can be shortened by adjusting the torch position and oxygen flow rate.
This study investigates the microstructure, hardness, and abrasive wear resistance of hypereutectic high-chromium white cast iron (3.76 wt.% C, 0.87 wt.% Si, 0.85 wt.% Mn, 17.36 wt.% Cr, 2.01 wt.% Mo and 0.53 wt.% Ni) under different heat treatment conditions. The as-cast microstructure consists of primary (Fe,Cr)7C3 carbides in an retained austenite and martensite matrix. Increasing the austenitizing temperature from 970 degrees C to 1100 degrees C promotes greater carbide dissolution, enriching the austenite with carbon and chromium, which lowers the Ms temperature and increases retained austenite content approximately with 20%. Quenching from 970 degrees C followed by tempering at 450-550 degrees C yields maximum hardness of 62-63 HRC, while quenching from 1100 degrees C followed by tempering at 550-600 degrees C induces secondary hardening through retained austenite transformation and precipitation of fine M23C6 carbides. The optimal heat treatment regime is austenitization at 1100 degrees C and tempering at 600 degrees C, it provides the best abrasive wear performance, reducing the wear rate to V = 9.467 & times; 10-6 g & centerdot;m-1 and increasing wear resistance to E = 105634 m & centerdot;g-1, representing a 33% improvement compared to the as-cast condition. The enhanced wear resistance is attributed to the combined effect of tempered martensite, primary M7C3 carbides, finely dispersed secondary carbides, and the transformation of retained austenite during abrasion.
