28 May 2025, Volume 45 Issue 5
    

  • Select all
    |
  • Original position analysis and characterization of composition of large-sized high temperature alloy bar
    DENG Canglong, JIA Yunhai, SHENG Liang, ZHANG Xiaofen, ZHANG Chunyan, LI Jianqiang
    Metallurgical Analysis. 2025, 45(5): 1-10. https://doi.org/10.13228/j.boyuan.issn1000-7571.012742
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    In research and development of high temperature alloy,the accurate characterization of global composition distribution characteristics of materials is of great significance for process optimization,service performance improvement,and material quality monitoring or evaluation.In this study,the global and regional composition distribution of GH4169 high temperature alloy bar sample was characterized using original position statistic distribution analysis system for ultra large metal components.Various key parameters were systematically optimized,and the optimal experimental conditions were finally determined as follows:the capacitance parameter was 0.10,the spark excitation frequency was 400 Hz,the scanning speed was 45 mm/min,the processing rotational speed was 250 r/min,and the electrode distance was 4.0 mm.A characterization and evaluation model for segregation degree of GH4169 high temperature alloy was established.The results showed that the selected GH4169 high temperature alloy sample had no defects in the central area.The product segregation could meet the standard range according to the standard sampling area evaluation.The global segregation analysis data indicated that on the whole,the uniformity of each element was good,but there was still room for improvement in the uniformity of Fe.The proposed method had guiding significance for the optimization of GH4169 high temperature alloy production process as well as the research and development of high-performance materials.
  • Research on microstructure classification of γ-TiAl based on laser-induced breakdown spectroscopy and deep learning model
    WANG Yinghao, CUI Minchao, DING Leiyi, SHAN Mengjie, LUO Ming, MA Nan, WANG Yuanbin
    Metallurgical Analysis. 2025, 45(5): 11-17. https://doi.org/10.13228/j.boyuan.issn1000-7571.012740
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    Online diagnosis and testing of γ-TiAl components in aircraft engines during processing and manufacturing is an important part for aircraft engine manufacturing and intelligent testing. Due to the fact that laser-induced breakdown spectroscopy(LIBS) technology can only be used to detect the elemental composition of materials,there is a lack of direct judgment on the microstructure of materials.In this study,the identification of γ-TiAl microstructure was realized based on the combination of LIBS with deep learning algorithms.In experiments,γ-TiAl samples were subjected to six different heat treatments to obtain different microstructures under electron microscope.Subsequently,LIBS experiments were conducted on γ-TiAl with different microstructures,and the obtained spectra were denoised through baseline correction and wavelet transform.In order to improve the simplicity and interpretability of the data,principal component analysis(PCA) was used to take the first 32 principal components as the dimensionality reduced data,which were used as the inputs for classification by three deep learning models, i.e.,BP neural network(BP),convolutional neural network(CNN),and long short-term memory neural network(LSTM).Among them,the LSTM model had the best performance with accuracy of 96.04%,while the BP and CNN models also had excellent results,with accuracy of 95.57% and 93.35%, respectively.Meanwhile,the training of three models was completed within 30 s.Therefore,the combination of LIBS and deep learning models could achieve the accurate classification of γ-TiAl with different microstructures,which provided new means and ideas for intelligent detection in industrial production in the future.
  • Study on modification effect of magnesium treatment on inclusions in thick plate steel
    ZHAO Xinyi, LUN Mingrui, SHEN Ping, FU Jianxun
    Metallurgical Analysis. 2025, 45(5): 18-25. https://doi.org/10.13228/j.boyuan.issn1000-7571.012637
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    Magnesium treatment of inclusions in steel has a good regulatory effect,thus improving the product quality and product performance.In order to investigate the modification effect and modification mechanism of magnesium treatment on inclusions in thick plate steel,the composition,morphology,size and distribution of inclusions in thick plate steel after calcium treatment and magnesium treatment were comparatively analyzed using metalloscope,scanning electron microscope (SEM),Aspex automatic analyzer for inclusions,and three-dimensional corrosion engraving device for inclusions.The studies showed that the size and density of inclusions were larger after calcium treatment,and the area of inclusions accounted for 0.020%,0.028%,and 0.022% in the inner arc,inner arc 1/4,and center of casting billet sample,respectively.After magnesium treatment,the size and density of inclusions were reduced.The area ratio of inclusions in the inner arc,inner arc 1/4,the center were all reduced,i.e.,0.014%,0.024%,and 0.016%,respectively.Compared with calcium treatment,the cleanliness of thick plate steel increased after magnesium treatment,and the number proportion of small-sized inclusions increased.The addition of Mg could modify the Al2O3 inclusions in steel into fine dispersed MgO·Al2O3 inclusions.MnS and MgS could form a solid solution (Mn,Mg)S, and a kind of outer-soft inner-hard composite inclusions with MgO·Al2O3 as the core was formed.The morphology was close to sphere or ellipsoid.
  • Application of focused ion beam double-beam system in the analysis of surface black spot defect of galvanized product
    SUN Xuejiao
    Metallurgical Analysis. 2025, 45(5): 26-33. https://doi.org/10.13228/j.boyuan.issn1000-7571.012713
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    In the analysis of black spot defects on the surface of galvanized product,the key point to find the cause of defects is to observe the defect depth into the sample matrix.However,for the shallow depth of defects into the matrix (less than 5 μm) and the small size of black spots (less than 1 mm),it is difficult for the traditional metallographic sample preparation method to meet the analysis requirements.Therefore,the problem of cross section sample preparation should be solved in the analysis.This paper described the precise positioning and micro/nano level in-situ cutting function by focused ion beam(FIB) double-beam system.High-quality cross section samples of the defect were dissected and prepared to optimally present the interface between the defect and the matrix.The heterogeneous composition at the defect was comprehensively characterized by combining with the surface scanning function of the energy dispersive spectrometer(EDS).By analyzing the morphology,composition and distribution of black spot defects on the galvanized product surface of two typical cases,it was determined that the causes of black spot defects were the external oxidation of Mn in the process of hot dip galvanizing,which damaged the wettability between zinc liquid and steel plate,and pressing in or not cleaning up of the surface oxide scale,which resulted in skip plating black spot,respectively.The case study proved that the in-situ characterization technique of focused ion beam double-beam system had obvious advantages in in-situ anatomy and cross section observation of defects.
  • Determination of vanadium and coexisting(associated)elements in vanadium ore by inductively coupled plasma atomic emission spectrometry with microwave digestion
    ZENG Jiangping, WANG Jiasong, WANG Liqiang, YU Yang, WANG Na
    Metallurgical Analysis. 2025, 45(5): 34-41. https://doi.org/10.13228/j.boyuan.issn1000-7571.012734
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    The comprehensive utilization of vanadium ore resources requires the accurate determination of its components.The vanadium ore resources in China are abundant,which mainly exist in vanadium-titanium magnetite and stone coal vanadium ore.The vanadium-titanium magnetite is a kind of ore which is hardly decomposed,while the stone coal vanadium ore contains high content of carbon or organic matters,so the decomposition of sample is usually incomplete.Moreover,vanadium and titanium are easily hydrolyzed.In this study,the sample was treated by microwave digestion in nitric acid-hydrofluoric acid system.V 310.230 nm,Ti 334.940 nm,Fe 239.562 nm,Al 396.153 nm,Co 228.616 nm,P 214.914 nm,Cu 327.393 nm and Mn 259.372 nm were selected as the analytical line of vanadium,titanium,iron,aluminum,cobalt,phosphorus,copper,and manganese,respectively.The method for determination of vanadium and coexisting(associated) elements(including iron,titanium,aluminum,cobalt,phosphorus,copper and manganese) in vanadium ore by inductively coupled plasma atomic emission spectrometry (ICP-AES) was established. The medium for test solution was 5%(volume fraction)hydrochloric acid in experiments to prevent the hydrolysis of vanadium and titanium.The linear correlation coefficients of calibration curves of elements were all higher than 0.999.The limit of detection of this method was in range of 20-158 μg/g.The proposed method was applied for the determination of vanadium,titanium,iron,aluminum,cobalt,phosphorus,copper,and manganese contents in certified reference materials (GBW07224 and GBW07875),and the relative standard deviations (RSD, n=12) of determination results were between 0.2% and 6.0%,which could meet the requirements of DZ/T 0130 The specification of testing quality management for geological laboratories.The determination results were basically consistent with the certified values,and the relative error(RE) was between -6.72% and 11.00%.GBW07877 and one vanadium ore sample were selected and determined according to the experimental method and ICP-AES after high-pressure closed acid dissolution.The results showed that the measurement values of two methods were consistent.
  • Determination of platinum,palladium and rhodium in automobile exhaust purification catalyst by inductively coupled plasma atomic emission spectrometry with fire assay enrichment
    DAI Dongqing, TANG Chen, ZHA Yanqing, YI Xizhen, WANG Dawei, FENG Yahui
    Metallurgical Analysis. 2025, 45(5): 42-48. https://doi.org/10.13228/j.boyuan.issn1000-7571.012729
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    The content of platinum,palladium,and rhodium has a significant impact on the performance and cost of automobile exhaust purification catalysts.Therefore,the accurate and convenient determination of platinum,palladium,and rhodium content in automobile exhaust purification catalysts is of great significance.In this study,the platinum,palladium and rhodium in automobile exhaust purification catalyst was enriched by the fire assay method.Subsequently,the obtained sample was dissolved with nitric acid-hydrochloric acid.Then the content of platinum,palladium and rhodium in the solution was determined by inductively coupled plasma atomic emission spectrometry (ICP-AES).The experimental parameters including fire assay ingredients,cupellation conditions and cupellation protective agents were optimized:75 mg of silver or gold was selected as the cupellation protective agent;25 g of sodium carbonate,150 g of lead oxide,15 g of borax,10 g of silicon dioxide,5 g of calcium fluoride and 3.5 g of starch were used as ingredients.These ingredients were melted with the sample at 900 ℃ to obtain the lead buttons followed by cupellation at 880-890 ℃.The linear correlation coefficient of calibration curves of elements was not less than 0.999 7.The limit of detection for elements in this method was in range of 0.99-1.65 μg/g,and the limit of quantification was in range of 3.3-5.5 mg/kg,respectively.The content of platinum,palladium and rhodium in three automobile exhaust purification catalyst samples was determined according to the experimental method.The relative standard deviation (RSD, n=9) of determination results was between 1.0% and 2.6%,and the recoveries were between 97% and 101%.The contents of platinum,palladium and rhodium in certified reference materials of waste automobile catalyst were determined according to the experimental method,and the measurement results were consistent with the certified values.
  • Exploring the influencing factors of carbon release based on orthogonal experimental method during the determination of carbon in titanium alloy by high frequency combustion infrared absorption
    LIU Qiaopeng
    Metallurgical Analysis. 2025, 45(5): 49-56. https://doi.org/10.13228/j.boyuan.issn1000-7571.012714
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    For the determination of carbon content in titanium alloy,the sample is usually treated by high-temperature combustion in an oxygen flow to release carbon in the form of carbon dioxide for detection.At present,the most mature method is high-frequency combustion coupled with infrared absorption analysis.However,there are still few systematic investigations on the types of flux and sample mass using this method for carbon determination in titanium alloy.In this study,three different brands of titanium alloys (TA2, TB13, and TC4) were selected.The effect of sample mass,flux mass,flux type,and the stacking order of flux and sample in the crucible on the melting efficiency of titanium alloy and the measurement results of carbon during the determination of carbon content in titanium alloy by high frequency combustion infrared absorption were systematically explored using orthogonal experimental method.The experimental results demonstrated that the sample mass exerted the most significant influence on the determination results of carbon, and the optimal sample mass was 0.2 g.For the type of flux,the melting effect was good when pure copper or copper+tin+iron (mCu∶mSn∶mFe=2∶1∶1) was selected as the flux.The combustion was complete without splashing.The peak shape was normally distributed without tailing.As the flux was mixed uniformly with the sample,the carbon release efficiency was optimal,and the measured results were most close to the reference values.For the flux mass,when the dosage of flux was 2.1 g,the release rate of carbon was the highest,and the requirements of GB/T 4698.14-2011 could be met.The content of carbon in titanium alloy certified reference material GBW(E)020180 was determined according to the optimized experimental method,and the relative standard deviation(RSD,n=11) was 0.53%.This study provided an optimized protocol for high-frequency combustion infrared absorption analysis of carbon in titanium alloy, and it had significant practical application value.
  • Determination of yttrium,neodymium and gadolinium in rare earth magnesium alloy by inductively coupled plasma atomic emission spectrometry
    YI Yunhu, WANG Meng, LIU Qi, SUN Hongfei, WU Jian, TIAN Yang
    Metallurgical Analysis. 2025, 45(5): 57-63. https://doi.org/10.13228/j.boyuan.issn1000-7571.012741
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    Yttrium,neodymium and gadolinium are important alloying elements of magnesium alloy,and greatly affect the properties of magnesium alloy.Therefore,the accurate determination and evaluation of their contents is of great importance.In this study,the problem of sample segregation was solved by equally spaced multipoint drilling and sampling.The sample was dissolved with HCl(1+1).Y 371.029 mn,Nd 430.358 nm and Gd 335.047 nm were selected as analysis lines for yttrium,neodymium and gadolinium,respectively.The matrix effect and interference of coexisting elements were investigated,and the interference among zirconium,neodymium and gadolinium was eliminated using interference coefficient correction method.The method for the determination of yttrium,neodymium and gadolinium in rare earth magnesium alloy by inductively coupled plasma atomic emission spectrometry (ICP-AES) was established.The linear correlation coefficients of calibration curves for yttrium,neodymium and gadolinium in linear range all reach 0.999 9.The limit of detection for elements in this method was in range of 0.000 002%-0.000 17%(mass fraction,similarly hereinafter),and the limit of quantification was in range of 0.000 005%-0.000 58%,respectively.The content of yttrium,neodymium and gadolinium in rare earth magnesium alloy samples was determined according to the experimental method,and the relative standard deviation(RSD, n=11) of determination results was 0.86%-6.6%,0.95%-2.4% and 0.82%-5.3% for yttrium,neodymium and gadolinium,respectively.The recovery was 98%-105%,99%-104% and 98%-103%,respectively.
  • Determination of 13 elements in carbon steel and middle-low alloy steel thin plate by spark discharge atomic emission spectrometry
    YANG Weifei
    Metallurgical Analysis. 2025, 45(5): 64-69. https://doi.org/10.13228/j.boyuan.issn1000-7571.012728
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    The chemical composition inspection of carbon steel and middle-low alloy steel thin plate plays a key role in the quality control of outgoing products and the development of new products.In experiments,the content of 13 elements in carbon steel and middle-low alloy steel thin plates,including C,Si,Mn,P,S,Cr,Ni,Cu,Al,Nb,V,Ti and N,were determined by spark discharge atomic emission spectrometry.The effects of sample preparation method, spectral excitation limit sample thickness and sample flatness were investigated,and the use of specific sample fixtures was also discussed.It was found that the sample with a thickness less than 0.30 mm should be polished with manual sandpaper,while sample with a thickness of 0.30-2.00 mm should be polished with a sand belt machine.The sample with a thickness less than 0.20 mm was not suitable for the determination by spark discharge atomic emission spectrometry.After using a special fixture and pressure block combination,the back of the sample almost showed no indentation or color change to blue.According to the experimental method,the carbon steel and middle-low alloy steel thin plate samples with different thicknesses were tested.The results showed that except for ultra-low carbon,sulfur and nitrogen,the relative standard deviations (RSD,n=10) of determination results of other elements were all less than 5%.The content of 13 elements in carbon steel and middle-low alloy steel thin plate samples with different thickness was determined according to the experimental method and national standard method (where C and S were determined according to GB/T 20123-2006,N was determined according to GB/T 20124-2006,and other elements were determined according to GB/T 20125-2006).The result showed that the determination values of two methods were consistent.The proposed method effectively solved the problem in the national standard GB/T 4336-2016 that samples with a thickness less than 2 mm could not be directly analyzed using spark discharge atomic emission spectrometry,and it expanded the thickness of carbon steel and middle-low alloy steel thin plate samples in direct inspection by spark discharge atomic emission spectrometry.
  • Determination of aluminium and iron in zinc alloy by X-ray fluorescence spectrometry
    SUN Zhuo, TIAN Yuwei, ZHANG Jianhua
    Metallurgical Analysis. 2025, 45(5): 70-75. https://doi.org/10.13228/j.boyuan.issn1000-7571.012683
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    When the inductively coupled plasma atomic emission spectrometry in standard method GB/T 12689.12-2004 is used to determine aluminum and iron in zinc alloy,the chemical pretreatment is time-consuming and the operation is cumbersome.In this study,the surface of zinc alloy sample was prepared using a fully automatic milling machine.The zinc alloy certified reference material/standard sample and nine zinc alloy production samples (1#-9#) where were certified by standard method GB/T 12689.12-2004 were used as calibration sample series to draw the calibration curves.The waiting time for sample analysis was controlled to be 0-5 min.The method for the determination of aluminum and iron in zinc alloy by X-ray fluorescence spectrometry (XRF) was established.The results indicated that the determination coefficient/correlation coefficient of the calibration curves for aluminum and iron were both not less than 0.999 5.The determination ranges for aluminum and iron were 0.117%-0.397% and 0.000 85%-0.023%,respectively.The limits of detection of this method were 7.46 and 4.21 μg/g,respectively.The content of aluminum and iron in three zinc alloy samples was determined according to the experimental method,and relative standard deviations (RSD, n=11) of the results were both less than 5%.The measured results of aluminum and iron in zinc alloy certified reference material/standard sample were consistent with the certified values/standard values.The experimental method and standard method GB/T 12689.12-2004 were used to determine aluminum and iron in zinc alloy production samples,and the absolute error could meet the requirements of the interlaboratory allowable difference in standard method GB/T 12689.12-2004.
  • Determination of samarium in magnesium alloy round ingot by inductively coupled plasma atomic emission spectrometry
    ZHANG Xilin, SUI Zhifang, SUN Zhiyang
    Metallurgical Analysis. 2025, 45(5): 76-80. https://doi.org/10.13228/j.boyuan.issn1000-7571.012743
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    As a kind of lightweight and high-strength metal material,the magnesium alloy round ingots are widely used in many fields such as automobiles,aerospace,and electronic equipment.Samarium is a rare earth element and it has a significant impact on the microstructure and mechanical properties of magnesium alloy round ingots.Therefore,the accurate determination of samarium content is of great significance for the study of the properties of magnesium alloy round ingots.The working conditions of the instrument were optimized in experiments.The matrix and coexisting elements,the dissolution process,the analytical spectral lines,and the standard working curve were investigated.The magnesium alloy round ingot sample was dissolved with 5 mL of hydrochloric acid (1+1).Sm 360.949 nm was selected as the analytical line.The samarium content in sample solution was determined by inductively coupled plasma atomic emission spectrometry (ICP-AES).The content of samarium in magnesium alloy round ingot samples was determined according to the experimental method.The relative standard deviation (RSD,n=6) of determination results was between 0.61% and 0.76%,and the recovery was between 98.4% and 100.8%.
  • Determination of acidity in steel pickling solution by ferrous photometric titration
    MENG Xianzhe, WANG Lanming
    Metallurgical Analysis. 2025, 45(5): 81-85. https://doi.org/10.13228/j.boyuan.issn1000-7571.012718
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    During the acid pickling process of steel,the acidity of pickling solution has a significant impact on the acid pickling quality of the workpiece.In this study,a new method for the determination of acidity in acid pickling solution containing FeCl2 was proposed by combining titration and photometry.FeCl2 itself in the steel pickling solution was used as the indicator.When the pH of testing solution changed abruptly,the Fe2+ would precipitate and the absorbance of solution increased significantly.The absorbance mutation point was taken as the end point of titration.The effects of wavelengths and FeCl2 concentration on the detection were investigated.It was found that there was a sudden change in absorbance of test solution at wavelength of 770 nm.The acidity could be detected in a wide range of FeCl2 mass concentration from 15 to 300 g/L.The relative error between the ferrous photometric titration and the acid-base titration method used to detect acidity of actual pickling solution was less than 1.7%,which could meet the detection requirements in production.
Copyright © Metallurgical Analysis, All Rights Reserved.
Tel: 010-62182398　
E-mail：yjfx@analysis.org.cn
Powered by Beijing Magtech Co. Ltd,.