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International Journal of minerals,metallurgy and materials 2019年第2期26卷 186-193页

作者： Peng Fei Yi min Cheng-jun Liu mao-fa Jiang Key Laboratory for Ecological metallurgy of multimetallic mineral ((ministry of Education)) School of metallurgy Northeastern University Key Laboratory for Ecological metallurgy of multimetallic mineral (ministry of Education)

For the control of surface defects in interstitial-free(IF) steel, quantitative metallographic analyses of near-surface inclusions and surface liquid flow detection via the nail-board tipping method were conducted. The results show that, at casting speeds of 0.8 and 1.0 m/min, a thin liquid mold flux layer forms and non-uniform floating of argon bubbles occurs, inducing the entrainment and subsequent entrapment of the liquid flux; fine inclusion particles of Al_2O_3 can also aggregate at the solidification front. At higher casting speeds of 1.4 and 1.6 m/min, the liquid mold flux can be entrained and carried deeper into the liquid steel pool because of strong level fluctuations of the liquid steel and the flux. The optimal casting speed is approximately 1.2 m/min, with the most favorable surface flow status and, correspondingly, the lowest number of inclusions near the slab surface.

关键词： non-metallic inclusions distribution casting speed surface flow

CO observations towards a sample of nearby galaxies

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Research in Astronomy and Astrophysics 2015年第6期15卷 785-801页

作者： fa-Cheng Li Yuan-Wei Wu Ye Xu Purple mountain Observatory & Key Laboratory for Radio Astronomy Chinese Academy of Sciences University of Chinese Academy of Sciences

We have simultaneously observed 12CO, laCO and clSo （J = 1 - 0） rotational transitions in the centers of a sample of 58 nearby spiral galaxies using the 13.7-m millimeter-wave telescope administered by Purple mountain Observatory. Forty-two galaxies were detected in 13CO emission, but there was a null detection for C180 emission with a cr upper limit of 2 mK. The central beam ratios, R, of 12CO and 13CO range mostly from 5 to 13, with an average value of 8.1 ±4.2, which is slightly lower than previous estimates for normal galaxies. Clear correlations are found between ^12CO and ^13CO luminosities. An average X factor of 1.44± 0.84 × 10^20 cm^-2 （K km s-l）-1 is slightly lower than that in the milky Way.

关键词： galaxies: ISm -- molecules galaxies -- millimeter lines ISm -- star formation ISm

Effects of diamond particle size on microstructure and properties of diamond/Al-12Si composites prepared by vacuum-assisted pressure infiltration

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China Foundry 2024年第4期21卷 360-368页

作者： Jia-ping Fu Can-xu Zhou Guo-fa mi Yuan Liu School of materials Science and Engineering Henan Polytechnic UniversityJiaozuo 454100HenanChina School of materials Science and Engineering Tsinghua UniversityBeijing 100084China Key Laboratory for Advanced materials Processing Technology Ministry of EducationBeijing 100084China

Diamond/aluminium composites have attracted attention in the field of thermal management of electronic packaging for their excellent *** order to solve the interfacial problem between diamond and aluminium,a novel process combining pressure infiltration with vacuum-assisted technology was proposed to prepare diamond/aluminum *** effect of diamond particle size on the microstructure and properties of the diamond/Al-12Si composites was *** results show that the diamond/Al-12Si composites exhibit high relative density and a uniform *** thermal conductivity and coefficient of thermal expansion increase with increasing particle size,while the bending strength exhibits the opposite *** the average diamond particle size increases from 45μm to 425μm,the thermal conductivity of the composites increases from 455 W·m^(-1)·K^(-1)to 713 W·m^(-1)·K^(-1)and the coefficient of thermal expansion increases from 4.97×10^(-6)K^(-1)to 6.72×10^(-6)K^(-1),while the bending strength decreases from 353 mPa to 246 *** research demonstrates that high-quality composites can be prepared by the vacuum-assisted pressure infiltration process and the thermal conductivity of the composites can be effectively improved by increasing the diamond particle size.

关键词： diamond/aluminum composites thermal conductivity electronic packaging vacuum-assisted pressure infiltration

Creep rupture behavior and microstructural evolution of modified 9Cr-1mo heat-resistant steel

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Journal of Iron and Steel Research International 2018年第12期25卷 1303-1310页

作者： fa-cai Ren He Wang Xiao-ying Tang Fei Chen Shanghai Institute of Special Equipment Inspection and Technical Research Shanghai 200062China Capital Aerospace machinery Corporation Limited Beijing 100076China National Engineering Research Centre of Die &mold CAD Shanghai Jiao Tong UniversityShanghai 200030China

High-temperature creep rupture behavior of modified 9Cr-lmo steel used for steam cooler was investigated at temperature of 838 and 923 K and stress ranging from 100 to 250 *** on the analysis of creep rate-time curves,it is found that the creep rupture life decreases with the increase in the applied stress and *** creep damage tolerance factor has been identified as a value of *** the normalized and tempered condition,the studied steel shows typical martensitic microstructure with Cr-rich m23C6 and Nb-or V-rich mX ***,the Laves phase has been found along the grain *** fracture morphology characterized by field emission scanning electron microscope is adopted to reveal the creep failure *** investigated results indicate the occurrence of the transgranular fracture under all the creep test conditions.

关键词： Creep rupture behavior modified 9Cr-1mo steel microstructural evolution Fractography

Effect of casting speed on dendrite arm spacing of mn13 steel continuous casting slab

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Journal of Iron and Steel Research International 2020年第6期27卷 665-672页

作者： Jian-min Li mao-fa Jiang Jun-xiang Ning Jun Zhai Key Laboratory for Ecological metallurgy of multimetallic Ores(ministry of Education) Northeastern UniversityShenyang110819LiaoningChina Shanxi Taigang Stainless Steel Co. Ltd.Taiyuan 030003ShanxiChina School of metallurgy Northeastern UniversityShenyang 110819LiaoningChina

The dendrite arm spacing in the continuous casting slab of mn13 steel under different casting speeds was measured using the metallographic microscope. meanwhile, a heat transfer model was established by the Pro-cast software. The relationship between the dendrite arm spacing and casting speed in continuous casting slab of mn13 steel was studied and described by a function expression. The results provide an important theoretical basis for the development and optimization of con-tinuous casting production process of high-manganese steel and help to improve the quality of continuous casting slab of high-manganese steel. Under the experimental conditions, the suitable casting speed is about 0.9 m/min. The secondary dendrite spacing maintains a relatively stable low-amplitude increase trend, and it is beneficial to obtain a higher proportion of equiaxed crystals.

关键词： High-manganese steel Dendrite arm spacing Continuous casting Casting speed

Cyclic oxidation behavior of NiCoCrAlY/YSZ@Ni composite coatings fabricated by laser cladding

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Journal of Iron and Steel Research International 2020年第10期27卷 1226-1235页

作者： Hai-zhong Zheng Pei-feng Zhou Gui-fa Li Ping Peng School of materials Science and Engineering Beihang UniversityBeijing 100191China School of material Science and Engineering Nanchang Hangkong UniversityNanchang 330063JiangxiChina School of material Science and Engineering Hunan UniversityChangsha 410082HunanChina

Composite coating on GH4169 alloy is prepared by laser cladding yttria-stabilized zirconia(YSZ)@Ni core-shell powdersmixed with NiCoCrAlY alloy *** cyclic oxidation behavior of the coatings,especially the growth process of theoxide layer,is investigated based on experimental research and first-principle *** results indicate that theoxidation resistance of coated GH4169 alloy is beer than that of uncoated GH4169 *** coating has three layers:acellular dendrite outer layer,a planar YSZ interlayer,and an inner layer composed of Cr2O3 formed during laser *** oxidation at 1000 and 1050℃,as the oxidation time increases,the cellular dendrite outer layer becomes thicker,andthe planar yttria-stabilized zirconia interlayer becomes *** the planar interlayer and Cr2O3 inner layer,and Al2O3 layer ***,cracks formed in the intcrface of Al2O3/Cr2O3 owing to thcir weak interface strength,whichled to the failure of the composite coating.

关键词： Laser cladding NiCoCrAlY/YSZ@Ni composite coating Cyelic oxidation-Oxidation mechanism.Crack nucleation

Effects and mechanisms of RE on Impact Toughness and Fracture Toughness of Clean Heavy Rail Steel

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Journal of Iron and Steel Research International 2011年第3期18卷 52-58页

作者： LIU Cheng-jun HUANG Ya-he JIANG mao-fa School of materials and metallurgy Northeastern UniversityShenyang 110004LiaoningChina

Clean high carbon heavy rail steel was prepared by the process of vacuum induction furnace smelting,forging and *** of RE on the impact toughness and fracture toughness for clean high carbon steel were *** addition,the appropriate range of RE content for clean high carbon steel was *** the austenite grain size and pearlite lamellar spacing decreased due to small amount of RE,consequently the impact toughness and fracture toughness were improved *** the RE content exceeded a critical value,the pearlite lamellar spacing was increased,because RE was segregated on the austenite grain boundaries,damaged the orientation relationship of pearlite transformation,caused the disorder growth and morphology degenerating of *** the increasing of RE content,both the impact toughness and fracture toughness of clean high carbon steel were gradually increased at first and then *** was found that when the RE content was between 0.0081% and 0.0088%,both the impact toughness and fracture toughness of clean high carbon heavy rail steel were the *** maximum ballistic work was 21.2 J（20 ℃） and 12.2 J（-20 ℃）,*** maximum plane-strain fracture toughness was 45.67 mPa·m1/2（20 ℃） and 37.04 mPa·m1/2（-20 ℃）,respectively.

关键词： rare earth high carbon steel heavy rail steel clean steel impact toughness fracture toughness

Growth behavior of spinel in stainless steel slag during cooling process

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Journal of Iron and Steel Research International 2018年第11期25卷 1131-1139页

作者： Long-hu Cao Cheng-jun Liu Qing Zhao mao-fa Jiang Key Laboratory for Ecological metallurgy of multimetallic Ores (ministry of Education) Northeastern University Shenyang 110819LiaoningChina School of metallurgy Northeastern University Shenyang 110819LiaoningChina

Spinel is an appropriate phase for sequestrating chromium in stainless steel slag to prevent chromium from polluting,and the crystal size of spinel has a significant effect on the stability of chromium and the extraction efficiency of *** enrichment behavior of chromium in spinel during cooling process was investigated,and the growth process of spinel was studied based on the crystal size distribution *** results showed that the enrichment degree of chromium in spinel increased from 88.5% to nearly 100% during the cooling process from 1773 to 1573 K at a rate of 5 K/*** mean diameter of spinel in stainless steel slag had an obvious growth in the cooling process,and a rapid growth of spinel occurred during the cooling process from 1623 to 1523 *** results indicated that the leaching amount of chro- mium could reduce to less than 0.01 mg/L by controlling the cooling *** growth mechanism of spinel was investigated and proposed to consist of two stages:in the first stage,the spinel was in the surface-controlled growth with a decaying nucleation rate from 1773 to 1573 K,and in the second stage,the growth mechanism was transformed to supply- controlled Ostwald ripening-below 1573 K.

关键词： Stainless steel slag Spinel Chromium Growth mechanism Crystal size distribution

Plant phenolic extracts for the quality protection of frying oil during deep frying:Sources,effects,and mechanisms

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Grain & Oil Science and Technology 2023年第3期6卷 148-161页

作者： fa Wang Yixi Sun Shanshan Li Jing Yan Wen Qin Ahmed S.m.Saleh Qing Zhang College of Food Science Sichuan Agricultural UniversityYa'anSichuanChina Key Laboratory of Agricultural Product Processing and Nutrition and Health of the ministry of Agriculture and Rural Affairs(Jointly Built by the ministry and the Province) Ya'anSichuanChina Department of Food Science and Technology Faculty of AgricultureAssiut UniversityEgypt

Protection of frying oil from deterioration by adding plant phenolic extracts to guarantee the quality of fried foods becomes the primary approach to promote the sustainable development of deep ***,sources,antioxidant effects,and mechanisms of plant phenolic extracts recently applied in the quality protection of frying oil as well as challenges for the actual use of these extracts are comprehensively reviewed in this ***,herbs,berries,tea leaves,and fruit and vegetable wastes are common sources for preparing phenolic extracts showing comparative antioxidant capacity referring to the synthetic *** general effect of using these natural antioxidants is the improvement of thermal stability to extend the shelf life of frying oil and thus the modification of edible quality of fried ***,the increases in common quality attributes and amount of hazardous products and the oxidative reduction of unsaturated triacylglycerols without negatively influencing the sensory quality are inhibited when suitable plant extracts are *** incorporation of plant phenolic extracts other than synthetic counterparts in frying oil has been demonstrated as a potential method to improve the frying performance of ***,challenges for the scale application of plant phenolic extracts,such as the purity,thermal stability,and antioxidant timing,are still needed to be further investigated.

关键词： Frying oil Phenolic antioxidants Plant extract Physicochemical properties Antioxidant mechanisms

Research on Flexural Behavior of Coral Aggregate Reinforced Concrete Beams

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China Ocean Engineering 2018年第5期32卷 593-604页

作者： mA Hai-yan DA Bo YU Hong-fa WU Zhang-yu Department of Civil Engineering Nanjing University of Aeronautics and Astronautics

Through the flexural behavior test of coral aggregate reinforced concrete beams(CARCB) and ordinary Portland reinforced concrete beams(OPRCB), and based on the parameters of concrete types, concrete strength grades and reinforcement ratios, the crack development, failure mode, midspan deflection and flexural capacity were studied, the relationships of bending moment-midspan deflection, load-longitudinal tensile reinforcement strain, load-maximum crack width were established, and a calculation model for the flexural capacity of CARCB was suggested. The results showed that with the increase in the reinforcement ratio and concrete strength grade, the crack bending moment(mcr)and ultimate bending moment(mu) of CARCB gradually increased. The characteristics of CARCB and OPRCB are basically the same. Furthermore, through increasing the concrete strength grade and reinforcement ratio, mcr/mu could be increased to delay the cracking of CARCB. As the load increased, crack width(w) would also increase. At the beginning of the loading, w increased slowly. And then it increased rapidly when the load reached to the ultimate load, which then led to beam failure. meanwhile, with a comprehensive consideration of the effects of steel corrosion on the loss of steel section and the decrease of steel yield strength, a more reasonable calculation model for the flexural capacity of CARCB was proposed.

关键词： coral aggregate reinforced concrete beam flexural behavior steel corrosion reinforcement ratio concrete strength calculation model