The corrosion behavior of high-strength low-alloy 921A steel in a simulated marine atmospheric environment was studied using a high-throughput experimental method.The corrosion behavior,corrosion morphology,and corros...The corrosion behavior of high-strength low-alloy 921A steel in a simulated marine atmospheric environment was studied using a high-throughput experimental method.The corrosion behavior,corrosion morphology,and corrosion products of 921A steels were analyzed using various techniques,including corrosion mass loss method,polarization curve,white-light interferometry,scanning electron microscopy,energy-dispersive spectrometry,microbeam X-ray fluorescence spectrometry,X-ray diffraction technique,and X-ray photoelectron spectroscopy.The test results indicated that 921A steel exhibits better corrosion resistance than Q450NQR1 steel in simulated harsh atmospheric environments,as evidenced by a lower corrosion mass loss rate throughout the corrosion tests.The corrosion products of both steels consisted ofα-FeOOH,Fe_(3)O_(4),andγ-FeOOH,withα-FeOOH being more prevalent in the rust layer of 921A steel than in Q450NQR1 steel.The inner rust layer of 921A steel also exhibited an appositional enrichment region of Cr,Ni,Mo,and V,leading to its superior corrosion resistance compared to that of Q450NQR1 steel.The efficacy of high-throughput accelerated corrosion experimental methods was highlighted for evaluating the corrosion resistance of steel materials in harsh environmental conditions.The findings suggest that 921A steel exhibits better corrosion resistance compared to Q450NQR1 steel and has the potential to be more suitable in harsh marine atmospheric environments.The characterization of the rust layer structures and composition reveals the parallel enrichment of certain elements in the inner rust layer of 921A steel,which enhances its corrosion resistance.展开更多
An innovative application of laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) technique in illustrating elemental distributions on stainless steel sheets was presented. The technique proved to...An innovative application of laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) technique in illustrating elemental distributions on stainless steel sheets was presented. The technique proved to be a systematic and accurate ap- proach in producing visual images or maps of elemental distributions at cross-sectional surface of a stainless steel sheet. Two stain- less steel sheets served as research objects: 3 mm×l 300 mm hot-rolled stainless steel plate and 1 mm×l 260 mm cold-rolled plate. The cross-sectional surfaces of the two samples at 1/4 position along the width direction were scanned (raster area -44 mm2 and 11 mm2) with a focused laser beam (wavelength 213 nm, diameter of laser crater 100 μm, and laser power 1.6 mJ) in a laser abla- tion chamber. The laser ablation system was coupled to a quadrupole ICP-MS, which made the detection of ion intensities of 27A1+, 44Ca+, 47Ti-, 55Mn+ and 56Fe+ within an area of interest possible. One-dimensional (ID) content line distribution maps and two- dimensional (2D) contour maps for specific positions or areas were plotted to indicate the element distribution of a target area with high accuracy. Statistic method was used to analyze the acquired data by calculating median contents, maximum segregation, sta- tistic segregation and content-frequency distribution.展开更多
This study developed a new high-throughput strategy,designated as hot-isostatic-pres sing-based microsynthesis approach(HIP-MSA),to optimize high-performance nickel-based superalloys in a rapid,efficient,and cost-effe...This study developed a new high-throughput strategy,designated as hot-isostatic-pres sing-based microsynthesis approach(HIP-MSA),to optimize high-performance nickel-based superalloys in a rapid,efficient,and cost-effective manner.A specific honeycomb-array structure containing 106 discrete cells was designed and optimized using finite element analysis(FEA)and then applied to create a combinatorial library consisting of 106 Ni-based superalloys with various Co,Nb and Ta concentrations.By integration with high-throughput characterization tools,extensive composition and phase structure data were collected quickly and efficiently.In the superalloys with higher amounts of Nb and Ta,the detrimentalηphase displaying needle-like morphology was observed,and its content(wt%)increased drastically with Ta and Nb contents increasing.However,the increase of Co addition in those alloys was confirmed to be surprisingly beneficial by significantly suppressing the formation ofηphase that was induced by high Nb and Ta contents.The zero-phasefraction(ZPF)line ofηphase was established,which is critical to design superalloy chemistry for superior micros tructural stability at high-temperature service conditions.展开更多
Microstructural classification is typically done manually by human experts,which gives rise to uncertainties due to subjectivity and reduces the overall efficiency.A high-throughput characterization is proposed based ...Microstructural classification is typically done manually by human experts,which gives rise to uncertainties due to subjectivity and reduces the overall efficiency.A high-throughput characterization is proposed based on deep learning,rapid acquisition technology,and mathematical statistics for the recognition,segmentation,and quantification of microstructure in weathering steel.The segmentation results showed that this method was accurate and efficient,and the segmentation of inclusions and pearlite phase achieved accuracy of 89.95%and 90.86%,respectively.The time required for batch processing by MIPAR software involving thresholding segmentation,morphological processing,and small area deletion was 1.05 s for a single image.By comparison,our system required only 0.102 s,which is ten times faster than the commercial software.The quantification results were extracted from large volumes of sequential image data(150 mm^(2),62,216 images,1024×1024 pixels),which ensure comprehensive statistics.Microstructure information,such as three-dimensional density distribution and the frequency of the minimum spatial distance of inclusions on the sample surface of 150 mm^(2),were quantified by extracting the coordinates and sizes of individual features.A refined characterization method for two-dimensional structures and spatial information that is unattainable when performing manually or with software is provided.That will be useful for understanding properties or behaviors of weathering steel,and reducing the resort to physical testing.展开更多
基金the National Key Research and Development Program of China(Grant No.2021YFB3702103).
文摘The corrosion behavior of high-strength low-alloy 921A steel in a simulated marine atmospheric environment was studied using a high-throughput experimental method.The corrosion behavior,corrosion morphology,and corrosion products of 921A steels were analyzed using various techniques,including corrosion mass loss method,polarization curve,white-light interferometry,scanning electron microscopy,energy-dispersive spectrometry,microbeam X-ray fluorescence spectrometry,X-ray diffraction technique,and X-ray photoelectron spectroscopy.The test results indicated that 921A steel exhibits better corrosion resistance than Q450NQR1 steel in simulated harsh atmospheric environments,as evidenced by a lower corrosion mass loss rate throughout the corrosion tests.The corrosion products of both steels consisted ofα-FeOOH,Fe_(3)O_(4),andγ-FeOOH,withα-FeOOH being more prevalent in the rust layer of 921A steel than in Q450NQR1 steel.The inner rust layer of 921A steel also exhibited an appositional enrichment region of Cr,Ni,Mo,and V,leading to its superior corrosion resistance compared to that of Q450NQR1 steel.The efficacy of high-throughput accelerated corrosion experimental methods was highlighted for evaluating the corrosion resistance of steel materials in harsh environmental conditions.The findings suggest that 921A steel exhibits better corrosion resistance compared to Q450NQR1 steel and has the potential to be more suitable in harsh marine atmospheric environments.The characterization of the rust layer structures and composition reveals the parallel enrichment of certain elements in the inner rust layer of 921A steel,which enhances its corrosion resistance.
基金Sponsored by National Major Instrument and Equipment Development Special Project of China(2011YQ14014710)
文摘An innovative application of laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) technique in illustrating elemental distributions on stainless steel sheets was presented. The technique proved to be a systematic and accurate ap- proach in producing visual images or maps of elemental distributions at cross-sectional surface of a stainless steel sheet. Two stain- less steel sheets served as research objects: 3 mm×l 300 mm hot-rolled stainless steel plate and 1 mm×l 260 mm cold-rolled plate. The cross-sectional surfaces of the two samples at 1/4 position along the width direction were scanned (raster area -44 mm2 and 11 mm2) with a focused laser beam (wavelength 213 nm, diameter of laser crater 100 μm, and laser power 1.6 mJ) in a laser abla- tion chamber. The laser ablation system was coupled to a quadrupole ICP-MS, which made the detection of ion intensities of 27A1+, 44Ca+, 47Ti-, 55Mn+ and 56Fe+ within an area of interest possible. One-dimensional (ID) content line distribution maps and two- dimensional (2D) contour maps for specific positions or areas were plotted to indicate the element distribution of a target area with high accuracy. Statistic method was used to analyze the acquired data by calculating median contents, maximum segregation, sta- tistic segregation and content-frequency distribution.
基金financially supported by the National Key Research and Development Program of China (No. 2016YFB0700300)the National Science and Technology Major Project of China (No.J2019-VI-0023-0140)+1 种基金Taishan Scholars Program of Shandong Province (No.tsqn201909081)Shandong Natural Science Foundation of China (No.ZR2020ZD05)
文摘This study developed a new high-throughput strategy,designated as hot-isostatic-pres sing-based microsynthesis approach(HIP-MSA),to optimize high-performance nickel-based superalloys in a rapid,efficient,and cost-effective manner.A specific honeycomb-array structure containing 106 discrete cells was designed and optimized using finite element analysis(FEA)and then applied to create a combinatorial library consisting of 106 Ni-based superalloys with various Co,Nb and Ta concentrations.By integration with high-throughput characterization tools,extensive composition and phase structure data were collected quickly and efficiently.In the superalloys with higher amounts of Nb and Ta,the detrimentalηphase displaying needle-like morphology was observed,and its content(wt%)increased drastically with Ta and Nb contents increasing.However,the increase of Co addition in those alloys was confirmed to be surprisingly beneficial by significantly suppressing the formation ofηphase that was induced by high Nb and Ta contents.The zero-phasefraction(ZPF)line ofηphase was established,which is critical to design superalloy chemistry for superior micros tructural stability at high-temperature service conditions.
基金supported by the National Key Research and Development Program of China(No.2017YFB0702303).
文摘Microstructural classification is typically done manually by human experts,which gives rise to uncertainties due to subjectivity and reduces the overall efficiency.A high-throughput characterization is proposed based on deep learning,rapid acquisition technology,and mathematical statistics for the recognition,segmentation,and quantification of microstructure in weathering steel.The segmentation results showed that this method was accurate and efficient,and the segmentation of inclusions and pearlite phase achieved accuracy of 89.95%and 90.86%,respectively.The time required for batch processing by MIPAR software involving thresholding segmentation,morphological processing,and small area deletion was 1.05 s for a single image.By comparison,our system required only 0.102 s,which is ten times faster than the commercial software.The quantification results were extracted from large volumes of sequential image data(150 mm^(2),62,216 images,1024×1024 pixels),which ensure comprehensive statistics.Microstructure information,such as three-dimensional density distribution and the frequency of the minimum spatial distance of inclusions on the sample surface of 150 mm^(2),were quantified by extracting the coordinates and sizes of individual features.A refined characterization method for two-dimensional structures and spatial information that is unattainable when performing manually or with software is provided.That will be useful for understanding properties or behaviors of weathering steel,and reducing the resort to physical testing.