It is well known that the poor corrosion resistance of magnesium alloys is a key factor limiting their application. Field exposure is the most reliable means to evaluate the atmospheric corrosion performance of magnesium alloys. This article reviews the field exposure corrosion behavior of magnesium alloys in typical atmospheric environments (including the marine atmosphere, industrial atmosphere, etc.) in recent years. According to the literature review, it was found that there are significant regional differences in the atmospheric corrosion behavior of magnesium alloys, which is the result of the coupling of multiple factors in the atmospheric environment. By investigating the corrosion rate and corrosion products of different types of magnesium alloys in different environments, the corrosion mechanism of magnesium alloys in different environments was summarized. Specifically, environmental parameters such as atmospheric temperature, relative humidity, CO2, and chloride ion deposition rates in the marine atmospheric environment can affect the corrosion behavior of magnesium alloys. The corrosion of magnesium alloys in different industrial atmospheric environments is mainly affected by atmospheric temperature and relative humidity, as well as atmospheric pollutants (such as SO2, CO2, NO2) and dust. This review provides assistance to the development of new corrosion-resistant magnesium alloys.
{"title":"Recent Progress on Atmospheric Corrosion of Field-Exposed Magnesium Alloys","authors":"Mengqi Wang, Lihui Yang, Hao Liu, Xiutong Wang, Yantao Li, Yanliang Huang","doi":"10.3390/met14091000","DOIUrl":"https://doi.org/10.3390/met14091000","url":null,"abstract":"It is well known that the poor corrosion resistance of magnesium alloys is a key factor limiting their application. Field exposure is the most reliable means to evaluate the atmospheric corrosion performance of magnesium alloys. This article reviews the field exposure corrosion behavior of magnesium alloys in typical atmospheric environments (including the marine atmosphere, industrial atmosphere, etc.) in recent years. According to the literature review, it was found that there are significant regional differences in the atmospheric corrosion behavior of magnesium alloys, which is the result of the coupling of multiple factors in the atmospheric environment. By investigating the corrosion rate and corrosion products of different types of magnesium alloys in different environments, the corrosion mechanism of magnesium alloys in different environments was summarized. Specifically, environmental parameters such as atmospheric temperature, relative humidity, CO2, and chloride ion deposition rates in the marine atmospheric environment can affect the corrosion behavior of magnesium alloys. The corrosion of magnesium alloys in different industrial atmospheric environments is mainly affected by atmospheric temperature and relative humidity, as well as atmospheric pollutants (such as SO2, CO2, NO2) and dust. This review provides assistance to the development of new corrosion-resistant magnesium alloys.","PeriodicalId":18461,"journal":{"name":"Metals","volume":"7 1","pages":""},"PeriodicalIF":2.9,"publicationDate":"2024-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142184940","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The aim of the present work is to evaluate the effect of ultrafast heating on the microstructure and mechanical properties of hot forming steel. The initial microstructure utilized in this study was a cold-rolled microstructure, and the test steel was heated to full austenitization at a rate of 200 °C/s, followed by water quenching. It was observed that the ultrafast heating process significantly refines both the prior austenite grains and martensite laths while inheriting high-density dislocations from the initial cold-rolled microstructure. Consequently, the coupling mechanism between dislocation strengthening and grain refinement strengthening remarkably enhanced both the yield strength and ultimate tensile strength of the test steel. Eventually, the yield strength of the hot forming steel reached 1524 MPa, along with an ultimate tensile strength of 2221 MPa and uniform elongation of 5.2%.
{"title":"The Effect of Ultrafast Heating on the Microstructure and Mechanical Properties of the 2.2 GPa Grade Hot Forming Steel","authors":"Mai Wang, Jiang Chang, Hongyi Wu, Zhenli Mi, Yanxin Wu, Qi Zhang","doi":"10.3390/met14091006","DOIUrl":"https://doi.org/10.3390/met14091006","url":null,"abstract":"The aim of the present work is to evaluate the effect of ultrafast heating on the microstructure and mechanical properties of hot forming steel. The initial microstructure utilized in this study was a cold-rolled microstructure, and the test steel was heated to full austenitization at a rate of 200 °C/s, followed by water quenching. It was observed that the ultrafast heating process significantly refines both the prior austenite grains and martensite laths while inheriting high-density dislocations from the initial cold-rolled microstructure. Consequently, the coupling mechanism between dislocation strengthening and grain refinement strengthening remarkably enhanced both the yield strength and ultimate tensile strength of the test steel. Eventually, the yield strength of the hot forming steel reached 1524 MPa, along with an ultimate tensile strength of 2221 MPa and uniform elongation of 5.2%.","PeriodicalId":18461,"journal":{"name":"Metals","volume":"32 1","pages":""},"PeriodicalIF":2.9,"publicationDate":"2024-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142184946","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
High-entropy alloys (HEAs) have emerged as a novel class of materials with exceptional mechanical and corrosion properties, offering promising applications in various engineering fields. However, optimizing their performance through advanced manufacturing techniques, like laser cladding, remains an area of active research. This study investigated the effects of laser energy density on the mechanical and electrochemical properties of CoCrFeMnNi HEA coatings applied to Q235 substrates. Utilizing X-ray diffraction (XRD), this study confirmed the formation of a single-phase face-centered cubic (FCC) structure in all coatings. The hardness of the coatings peaked at 210 HV with a laser energy density of 50 J/mm2. Friction and wear tests highlighted that a coating applied at 60 J/mm2 exhibited the lowest wear rate, primarily due to adhesive and oxidative wear mechanisms, while the 55 J/mm2 coating showed increased hardness but higher abrasive wear. Electrochemical testing revealed superior corrosion resistance for the 60 J/mm2 coating, with a slow corrosion rate and minimal passivation tendency in contrast to the 55 J/mm2 coating. The comprehensive evaluation indicates that the HEA coating with an energy density of 60 J/mm2 exhibits exceptional wear and corrosion resistance.
{"title":"Effect of Laser Energy Density on the Properties of CoCrFeMnNi High-Entropy Alloy Coatings on Steel by Laser Cladding","authors":"Chenchen Ding, Qi Zhang, Siyu Sun, Hongjun Ni, Yu Liu, Xiao Wang, Xiaofeng Wan, Hui Wang","doi":"10.3390/met14090997","DOIUrl":"https://doi.org/10.3390/met14090997","url":null,"abstract":"High-entropy alloys (HEAs) have emerged as a novel class of materials with exceptional mechanical and corrosion properties, offering promising applications in various engineering fields. However, optimizing their performance through advanced manufacturing techniques, like laser cladding, remains an area of active research. This study investigated the effects of laser energy density on the mechanical and electrochemical properties of CoCrFeMnNi HEA coatings applied to Q235 substrates. Utilizing X-ray diffraction (XRD), this study confirmed the formation of a single-phase face-centered cubic (FCC) structure in all coatings. The hardness of the coatings peaked at 210 HV with a laser energy density of 50 J/mm2. Friction and wear tests highlighted that a coating applied at 60 J/mm2 exhibited the lowest wear rate, primarily due to adhesive and oxidative wear mechanisms, while the 55 J/mm2 coating showed increased hardness but higher abrasive wear. Electrochemical testing revealed superior corrosion resistance for the 60 J/mm2 coating, with a slow corrosion rate and minimal passivation tendency in contrast to the 55 J/mm2 coating. The comprehensive evaluation indicates that the HEA coating with an energy density of 60 J/mm2 exhibits exceptional wear and corrosion resistance.","PeriodicalId":18461,"journal":{"name":"Metals","volume":"56 1","pages":""},"PeriodicalIF":2.9,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142184952","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Sergei Mancerov, Andrey Kurkin, Maksim Anosov, Dmitrii Shatagin, Mikhail Chernigin, Julia Mordovina
Currently, the focus of production is shifting towards the use of innovative manufacturing techniques and away from traditional methods. Additive manufacturing technologies hold great promise for creating industrial products. The industry aims to enhance the reliability of individual components and structural elements, as well as the ability to accurately anticipate component failure, particularly due to fatigue. This paper explores the possibility of predicting component failure in parts produced using the WAAM (wire arc additive manufacturing) method by employing fractal dimension analysis. Additionally, the impact of manufacturing imperfections and various heat treatment processes on the fatigue resistance of 30CrMnSi steel has been investigated. Fatigue testing of samples and actual components fabricated via the WAAM process was conducted in this study. The destruction of the examined specimens and products was predicted by evaluating the fractal dimensions of micrographs acquired at different stages of fatigue testing. It has been established that technological defects are more dangerous in terms of fatigue failure than microstructural ones. The correctly selected mode of heat treatment for metal after electric arc welding allows for a more homogeneous microstructure with a near-complete absence of microstructural defects. A comparison of the fractal dimension method with other damage assessment methods shows that it has high accuracy in predicting part failure and is less labor-intensive than other methods.
{"title":"Prediction of Failure Due to Fatigue of Wire Arc Additive Manufacturing-Manufactured Product","authors":"Sergei Mancerov, Andrey Kurkin, Maksim Anosov, Dmitrii Shatagin, Mikhail Chernigin, Julia Mordovina","doi":"10.3390/met14090995","DOIUrl":"https://doi.org/10.3390/met14090995","url":null,"abstract":"Currently, the focus of production is shifting towards the use of innovative manufacturing techniques and away from traditional methods. Additive manufacturing technologies hold great promise for creating industrial products. The industry aims to enhance the reliability of individual components and structural elements, as well as the ability to accurately anticipate component failure, particularly due to fatigue. This paper explores the possibility of predicting component failure in parts produced using the WAAM (wire arc additive manufacturing) method by employing fractal dimension analysis. Additionally, the impact of manufacturing imperfections and various heat treatment processes on the fatigue resistance of 30CrMnSi steel has been investigated. Fatigue testing of samples and actual components fabricated via the WAAM process was conducted in this study. The destruction of the examined specimens and products was predicted by evaluating the fractal dimensions of micrographs acquired at different stages of fatigue testing. It has been established that technological defects are more dangerous in terms of fatigue failure than microstructural ones. The correctly selected mode of heat treatment for metal after electric arc welding allows for a more homogeneous microstructure with a near-complete absence of microstructural defects. A comparison of the fractal dimension method with other damage assessment methods shows that it has high accuracy in predicting part failure and is less labor-intensive than other methods.","PeriodicalId":18461,"journal":{"name":"Metals","volume":"34 1","pages":""},"PeriodicalIF":2.9,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142184951","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
γ-Fe2O3@SiO2-Ag nanocomposite coatings were prepared to investigate the lubrication performances of the nanocomposite coatings under a wide range of temperatures. The effect of Ag doping on the tribological properties of γ-Fe2O3@SiO2-Ag nanocomposite coatings was studied from room temperature to 600 °C, and the synergistic effect of Ag and oxides in the nanocomposite coatings was investigated. The coefficient of friction and the wear rate of γ-Fe2O3@SiO2-Ag nanocomposite coatings decrease with an increase in Ag content. The tribological properties of 24 wt.%Ag of the nanocomposite coatings are excellent. The stable coefficient of friction is 0.25 at 100 °C and the coefficient of friction is reduced to 0.05 at 500 °C. It was found that the synergistic effect of γ-Fe2O3 and Ag is helpful in improving the tribological properties of γ-Fe2O3@SiO2-Ag nanocomposite coatings over a wide temperature range. Ag plays a lubricating role at low and medium temperatures and oxides play a role in lubrication at high temperatures.
制备了γ-Fe2O3@SiO2-银纳米复合涂层,研究了纳米复合涂层在宽温度范围内的润滑性能。研究了从室温到 600 °C,Ag 掺杂对 γ-Fe2O3@SiO2-Ag 纳米复合涂层摩擦学性能的影响,并考察了纳米复合涂层中 Ag 和氧化物的协同效应。γ-Fe2O3@SiO2-Ag纳米复合涂层的摩擦系数和磨损率随Ag含量的增加而降低。24 wt.%Ag 纳米复合材料涂层的摩擦学性能优异。100 °C 时的稳定摩擦系数为 0.25,500 °C 时的摩擦系数降至 0.05。研究发现,γ-Fe2O3 和 Ag 的协同作用有助于改善γ-Fe2O3@SiO2-Ag 纳米复合涂层在宽温度范围内的摩擦学性能。银在中低温下起润滑作用,而氧化物在高温下起润滑作用。
{"title":"Influence of Ag Doping on Wide-Emperature Tribological Properties of γ-Fe2O3@SiO2 Nanocomposite Coatings on Steel","authors":"Qunfeng Zeng, Shichuan Sun, Qian Jia","doi":"10.3390/met14090996","DOIUrl":"https://doi.org/10.3390/met14090996","url":null,"abstract":"γ-Fe2O3@SiO2-Ag nanocomposite coatings were prepared to investigate the lubrication performances of the nanocomposite coatings under a wide range of temperatures. The effect of Ag doping on the tribological properties of γ-Fe2O3@SiO2-Ag nanocomposite coatings was studied from room temperature to 600 °C, and the synergistic effect of Ag and oxides in the nanocomposite coatings was investigated. The coefficient of friction and the wear rate of γ-Fe2O3@SiO2-Ag nanocomposite coatings decrease with an increase in Ag content. The tribological properties of 24 wt.%Ag of the nanocomposite coatings are excellent. The stable coefficient of friction is 0.25 at 100 °C and the coefficient of friction is reduced to 0.05 at 500 °C. It was found that the synergistic effect of γ-Fe2O3 and Ag is helpful in improving the tribological properties of γ-Fe2O3@SiO2-Ag nanocomposite coatings over a wide temperature range. Ag plays a lubricating role at low and medium temperatures and oxides play a role in lubrication at high temperatures.","PeriodicalId":18461,"journal":{"name":"Metals","volume":"194 1","pages":""},"PeriodicalIF":2.9,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142184954","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jin Ikegawa, Shiyu Wang, Ken Saito, Shinichi Kato, Kazuhiko Yamazaki, Shinsuke Suzuki
The objective of this study is to clarify the effect of spherical cementite (θ) precipitation on the occurrence of delayed fracture in 1.5 GPa grade tempered martensitic steels. Constant load tests were performed with a cathodically charged specimen. A 1GPa-load was applied to the specimen, and cathodic charging was performed in 3% NaCl + 3 g/L NH4SCN solution. The specimen of steel without spherical θ did not fracture at the current density of 5 A·m−2 or even by increasing to 50 A·m−2. On the other hand, the specimen of steel with spherical θ fractured after 0.2 h at 5 A·m−2. The strain around the spherical θ after 30%-rolling observed by transmission electron backscatter diffraction showed that the local deformation around the spherical θ was larger than that in the whole measurement field by 3.05 × 1014 m−2 in terms of geometrically necessary dislocation density. In the hydrogen desorption curve by thermal desorption analysis, steel with spherical θ after 30%-rolling showed a larger hydrogen desorption peak around 250 °C than steel without spherical θ. The value of the activation energy of the 250 °C-peak was 109.2 kJ·mol−1. From these results, the 250 °C-peak is inferred to be hydrogen at the disordered interface of θ/tempered martensite. Transmission electron microscopy observation showed cracks and voids on the spherical θ near the delayed fracture surface. These results indicate that the precipitation of spherical θ facilitates the occurrence of delayed fracture. Cracks appear to form around spherical θ.
{"title":"Effect of Spherical θ Precipitation in 1.5 GPa Grade Tempered Martensitic Steel on the Occurrence of Delayed Fracture","authors":"Jin Ikegawa, Shiyu Wang, Ken Saito, Shinichi Kato, Kazuhiko Yamazaki, Shinsuke Suzuki","doi":"10.3390/met14090999","DOIUrl":"https://doi.org/10.3390/met14090999","url":null,"abstract":"The objective of this study is to clarify the effect of spherical cementite (θ) precipitation on the occurrence of delayed fracture in 1.5 GPa grade tempered martensitic steels. Constant load tests were performed with a cathodically charged specimen. A 1GPa-load was applied to the specimen, and cathodic charging was performed in 3% NaCl + 3 g/L NH4SCN solution. The specimen of steel without spherical θ did not fracture at the current density of 5 A·m−2 or even by increasing to 50 A·m−2. On the other hand, the specimen of steel with spherical θ fractured after 0.2 h at 5 A·m−2. The strain around the spherical θ after 30%-rolling observed by transmission electron backscatter diffraction showed that the local deformation around the spherical θ was larger than that in the whole measurement field by 3.05 × 1014 m−2 in terms of geometrically necessary dislocation density. In the hydrogen desorption curve by thermal desorption analysis, steel with spherical θ after 30%-rolling showed a larger hydrogen desorption peak around 250 °C than steel without spherical θ. The value of the activation energy of the 250 °C-peak was 109.2 kJ·mol−1. From these results, the 250 °C-peak is inferred to be hydrogen at the disordered interface of θ/tempered martensite. Transmission electron microscopy observation showed cracks and voids on the spherical θ near the delayed fracture surface. These results indicate that the precipitation of spherical θ facilitates the occurrence of delayed fracture. Cracks appear to form around spherical θ.","PeriodicalId":18461,"journal":{"name":"Metals","volume":"20 1","pages":""},"PeriodicalIF":2.9,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142184953","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Dianxian Zhan, Dezhi Jiang, Yonggang Tong, Mingjun Zhang, Jian Zhang, Hongwei Hu, Zhenlin Zhang, Kaiming Wang
Offshore wind turbine generators usually demand higher requirements for key component materials because of the adverse working environment. Therefore, in this study, electromagnetic-assisted laser cladding technology was introduced to prepare the nickel-based composite coating on the Q345R matrix of wind turbine generator key component material. By means of Scanning Electron Microscope (SEM), X-ray diffraction (XRD), Energy Dispersive Spectrometer (EDS), the Vickers hardness tester, friction and wear tester, and electrochemical workstation, the effects of different magnetic field intensities on the macroscopic morphology, microstructure, phase composition, microhardness, wear resistance, and corrosion resistance of the coating were analyzed. The experimental results show that the addition of a magnetic field can effectively reduce the surface defects, improve the surface morphology, and not change the phase composition of the coating. With the increase in magnetic field intensity, the microstructure is gradually refined, and the average microhardness increases gradually, reaching a maximum of 944HV0.5 at 8 T. The wear resistance gradually increases with the increase in magnetic field intensity, especially when the magnetic field intensity reaches 12 T, the wear rate of the coating is reduced by 81.13%, and the corrosion current density is reduced by 43.7% compared with the coating without a magnetic field. The addition of an electromagnetic field can enhance the wear resistance and corrosion resistance of the nickel-based laser cladding layer.
由于工作环境恶劣,海上风力发电机通常对关键部件材料提出了更高的要求。因此,本研究引入电磁辅助激光熔覆技术,在风力发电机关键部件材料 Q345R 基体上制备镍基复合涂层。通过扫描电子显微镜 (SEM)、X 射线衍射 (XRD)、能量色散光谱仪 (EDS)、维氏硬度计、摩擦磨损试验机和电化学工作站,分析了不同磁场强度对涂层的宏观形貌、微观结构、相组成、显微硬度、耐磨性和耐腐蚀性的影响。实验结果表明,加入磁场能有效减少表面缺陷,改善表面形貌,且不改变涂层的相组成。随着磁场强度的增加,微观结构逐渐细化,平均显微硬度逐渐增加,在 8 T 时达到最大值 944HV0.5;耐磨性随着磁场强度的增加逐渐增加,特别是当磁场强度达到 12 T 时,与无磁场涂层相比,涂层的磨损率降低了 81.13%,腐蚀电流密度降低了 43.7%。加入电磁场可以提高镍基激光熔覆层的耐磨性和耐腐蚀性。
{"title":"Effect of Electromagnetic Field Assistance on the Wear and Corrosion Resistance of Nickel-Based Coating by Laser Cladding","authors":"Dianxian Zhan, Dezhi Jiang, Yonggang Tong, Mingjun Zhang, Jian Zhang, Hongwei Hu, Zhenlin Zhang, Kaiming Wang","doi":"10.3390/met14090998","DOIUrl":"https://doi.org/10.3390/met14090998","url":null,"abstract":"Offshore wind turbine generators usually demand higher requirements for key component materials because of the adverse working environment. Therefore, in this study, electromagnetic-assisted laser cladding technology was introduced to prepare the nickel-based composite coating on the Q345R matrix of wind turbine generator key component material. By means of Scanning Electron Microscope (SEM), X-ray diffraction (XRD), Energy Dispersive Spectrometer (EDS), the Vickers hardness tester, friction and wear tester, and electrochemical workstation, the effects of different magnetic field intensities on the macroscopic morphology, microstructure, phase composition, microhardness, wear resistance, and corrosion resistance of the coating were analyzed. The experimental results show that the addition of a magnetic field can effectively reduce the surface defects, improve the surface morphology, and not change the phase composition of the coating. With the increase in magnetic field intensity, the microstructure is gradually refined, and the average microhardness increases gradually, reaching a maximum of 944HV0.5 at 8 T. The wear resistance gradually increases with the increase in magnetic field intensity, especially when the magnetic field intensity reaches 12 T, the wear rate of the coating is reduced by 81.13%, and the corrosion current density is reduced by 43.7% compared with the coating without a magnetic field. The addition of an electromagnetic field can enhance the wear resistance and corrosion resistance of the nickel-based laser cladding layer.","PeriodicalId":18461,"journal":{"name":"Metals","volume":"66 1","pages":""},"PeriodicalIF":2.9,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142184961","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Andrej Škrlec, Branislav Panić, Marko Nagode, Jernej Klemenc
Cowper–Symonds parameters were estimated for the complex-phase high-strength steel with a commercial name of SZBS800. The parameter estimation was based on a series of conventional tensile tests and unconventional high-strain rate experiments. The parameters were estimated using a reverse engineering approach. LS-Dyna was used for numerical simulations, and the material’s response was modelled using a piece-wise linear plasticity model with a visco-plastic formulation of the Cowper–Symonds material model. A multi-criteria cost function was defined and applied to obtain a response function for the parameters p and C. The cost function was modelled with a response surface, and the optimal parameters were estimated using a real-valued genetic algorithm. The main novelty and innovation of this article is the definition of a cost function that measures a deviation between the deformed geometry of the flat plate-like specimens and the results of the numerical simulations. The results are compared to the relevant literature. A critical evaluation of our results and references is another novelty of this article.
{"title":"Estimating the Cowper–Symonds Parameters for High-Strength Steel Using DIC Combined with Integral Measures of Deviation","authors":"Andrej Škrlec, Branislav Panić, Marko Nagode, Jernej Klemenc","doi":"10.3390/met14090992","DOIUrl":"https://doi.org/10.3390/met14090992","url":null,"abstract":"Cowper–Symonds parameters were estimated for the complex-phase high-strength steel with a commercial name of SZBS800. The parameter estimation was based on a series of conventional tensile tests and unconventional high-strain rate experiments. The parameters were estimated using a reverse engineering approach. LS-Dyna was used for numerical simulations, and the material’s response was modelled using a piece-wise linear plasticity model with a visco-plastic formulation of the Cowper–Symonds material model. A multi-criteria cost function was defined and applied to obtain a response function for the parameters p and C. The cost function was modelled with a response surface, and the optimal parameters were estimated using a real-valued genetic algorithm. The main novelty and innovation of this article is the definition of a cost function that measures a deviation between the deformed geometry of the flat plate-like specimens and the results of the numerical simulations. The results are compared to the relevant literature. A critical evaluation of our results and references is another novelty of this article.","PeriodicalId":18461,"journal":{"name":"Metals","volume":"22 1","pages":""},"PeriodicalIF":2.9,"publicationDate":"2024-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142184955","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Sergey N. Grigoriev, Ivan V. Tambovskiy, Tatiana L. Mukhacheva, Irina A. Kusmanova, Pavel A. Podrabinnik, Nikolay O. Khmelevsky, Igor V. Suminov, Sergei A. Kusmanov
The paper investigates the feasibility of plasma electrolytic treatment (PET) of 90CrSi tool steel to enhance hardness and wear resistance. The influence of electrophysical parameters of PET (polarity of the active electrode, chemical-thermal treatment, and polishing modes) on the composition, structure, morphology, and tribological properties of the surface was studied. Tribological tests were carried out under dry friction conditions according to the shaft-bushing scheme with fixation of the friction coefficient and temperature in the friction contact zone, measurements of surface microgeometry parameters, morphological analysis of friction tracks, and weight wear. The formation of a surface hardened to 1110–1120 HV due to the formation of quenched martensite is shown. Features of nitrogen diffusion during anodic PET and cathodic PET were revealed, and diffusion coefficients were calculated. The wear resistance of the surface of 90CrSi steel increased by 5–9 times after anodic PET followed by polishing, by 16 times after cathodic PET, and up to 32 times after subsequent polishing. It is shown that in all cases, the violation of frictional bonds occurs through the plastic displacement of the material, and the wear mechanism is fatigue wear during dry friction and plastic contact.
本文研究了对 90CrSi 工具钢进行等离子电解处理(PET)以提高硬度和耐磨性的可行性。研究了 PET 的电物理参数(活性电极极性、化学热处理和抛光模式)对表面成分、结构、形态和摩擦学特性的影响。根据轴-衬套方案,在干摩擦条件下进行了摩擦学试验,固定了摩擦接触区的摩擦系数和温度,测量了表面微观几何参数、摩擦轨迹形态分析和重量磨损。结果表明,由于淬火马氏体的形成,表面硬化至 1110-1120 HV。揭示了阳极 PET 和阴极 PET 期间氮扩散的特征,并计算了扩散系数。90CrSi 钢表面的耐磨性在阳极 PET 后抛光后提高了 5-9 倍,在阴极 PET 后提高了 16 倍,在后续抛光后提高了 32 倍。结果表明,在所有情况下,摩擦结合的破坏都是通过材料的塑性位移发生的,磨损机理是干摩擦和塑性接触过程中的疲劳磨损。
{"title":"Features of Increasing the Wear Resistance of 90CrSi Tool Steel Surface under Various Electrophysical Parameters of Plasma Electrolytic Treatment","authors":"Sergey N. Grigoriev, Ivan V. Tambovskiy, Tatiana L. Mukhacheva, Irina A. Kusmanova, Pavel A. Podrabinnik, Nikolay O. Khmelevsky, Igor V. Suminov, Sergei A. Kusmanov","doi":"10.3390/met14090994","DOIUrl":"https://doi.org/10.3390/met14090994","url":null,"abstract":"The paper investigates the feasibility of plasma electrolytic treatment (PET) of 90CrSi tool steel to enhance hardness and wear resistance. The influence of electrophysical parameters of PET (polarity of the active electrode, chemical-thermal treatment, and polishing modes) on the composition, structure, morphology, and tribological properties of the surface was studied. Tribological tests were carried out under dry friction conditions according to the shaft-bushing scheme with fixation of the friction coefficient and temperature in the friction contact zone, measurements of surface microgeometry parameters, morphological analysis of friction tracks, and weight wear. The formation of a surface hardened to 1110–1120 HV due to the formation of quenched martensite is shown. Features of nitrogen diffusion during anodic PET and cathodic PET were revealed, and diffusion coefficients were calculated. The wear resistance of the surface of 90CrSi steel increased by 5–9 times after anodic PET followed by polishing, by 16 times after cathodic PET, and up to 32 times after subsequent polishing. It is shown that in all cases, the violation of frictional bonds occurs through the plastic displacement of the material, and the wear mechanism is fatigue wear during dry friction and plastic contact.","PeriodicalId":18461,"journal":{"name":"Metals","volume":"53 1","pages":""},"PeriodicalIF":2.9,"publicationDate":"2024-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142184957","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The use of low-carbon unalloyed steel with minimal silicon content is widespread in structural steel and automotive applications due to its ease of manipulation. The mechanical properties of this steel can be significantly enhanced through severe plastic deformation (SPD) techniques. Our study focuses on the practical benefits of the dual rolling equal channel extrusion (DRECE) method, which strengthens the steel and has implications for material hardness and the thickness of subsequently applied hot-dip zinc galvanizing. Furthermore, the steel’s corrosion potential and current are investigated as a function of material hardness and thickness. The findings show a 20% increase in hardness HV 30 after the first run through the forming machine, with an additional 10% increase after the second run. Subsequent galvanizing leads to a further 1–12% increase in HV 30 value. Notably, the DRECE hardening demonstrates no statistically significant effect on the corrosion potential and current; however, the impact of galvanizing is as anticipated.
{"title":"Low-Carbon Steel Formed by DRECE Method with Hot-Dip Zinc Galvanizing and Potentiodynamic Polarization Tests to Study Its Corrosion Behavior","authors":"Jiřina Vontorová, Vlastimil Novák, Petra Váňová","doi":"10.3390/met14090993","DOIUrl":"https://doi.org/10.3390/met14090993","url":null,"abstract":"The use of low-carbon unalloyed steel with minimal silicon content is widespread in structural steel and automotive applications due to its ease of manipulation. The mechanical properties of this steel can be significantly enhanced through severe plastic deformation (SPD) techniques. Our study focuses on the practical benefits of the dual rolling equal channel extrusion (DRECE) method, which strengthens the steel and has implications for material hardness and the thickness of subsequently applied hot-dip zinc galvanizing. Furthermore, the steel’s corrosion potential and current are investigated as a function of material hardness and thickness. The findings show a 20% increase in hardness HV 30 after the first run through the forming machine, with an additional 10% increase after the second run. Subsequent galvanizing leads to a further 1–12% increase in HV 30 value. Notably, the DRECE hardening demonstrates no statistically significant effect on the corrosion potential and current; however, the impact of galvanizing is as anticipated.","PeriodicalId":18461,"journal":{"name":"Metals","volume":"12 1","pages":""},"PeriodicalIF":2.9,"publicationDate":"2024-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142184956","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}