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Unexpected Twinning and Phase-Transition of the Indentation Standards, Their Transition Energies, and Scientific Dichotomy

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Journal of Applied Mathematics and Physics 2024年第6期12卷 2119-2159页

作者： Gerd Kaupp Department of Chemistry University of Oldenburg Oldenburg Germany

The general use of aluminium as an indentation standard for the iteration of contact heights for the determination of ISO-14577 hardness and elastic modulus is challenged because of as yet not appreciated phase-changes in the physical force-depth standard curve that seemed to be secured by claims from 1992. The physical and mathematical analyses with closed formulas avoid the still world-wide standardized energy-law violation by not reserving 33.33% (h2 belief) (or 20% h3/2 physical law) of the loading force and thus energy for all not depth producing events but using 100% for the depth formation is a severe violation of the energy law. The not depth producing part of the indentation work cannot be done with zero energy! Both twinning and structural phase-transition onsets and normalized phase-transition energies are now calculated without iterations but with physically correct closed arithmetic equations. These are reported for Berkovich and cubecorner indentations, including their comparison on geometric grounds and an indentation standard without mechanical twinning is proposed. Characteristic data are reported. This is the first detection of the indentation twinning of aluminium at room temperature and the mechanical twinning of fused quartz is also new. Their disqualification as indentation standards is established. Also, the again found higher load phase-transitions disqualify aluminium and fused quartz as ISO-ASTM 14577 (International Standardization Organization and American Society for Testing and Materials) standards for the contact depth “hc” iterations. The incorrect and still world-wide used black-box values for H- and Er-values (the latter are still falsely called “Young’s moduli” even though they are not directional) and all mechanical properties that depend on them. They lack relation to bulk moduli from compression experiments. Experimentally obtained and so published force vs depth parabolas always follow the linear FN = kh3/2 + Fa equation, where Fa is the axis-cut before and after the phase-tr

关键词： aluminium Fused Quartz Copper Twinning Structural Phase-Transitions Undue Indentation Standards Data Manipulation ZerodurR Absolute Hardness

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Speciation analysis of aluminium in plant parts of Betula pendula and in soil

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Journal of Environmental Sciences 2018年第3期30卷 153-161页

作者： Anetta Ziola-Frankowska Marcin Frankowski Adam Mickiewicz University in Poznan Faculty of Chemistry Department of Analytical Chemistry 61-614 Poznan Poland. Adam Mickiewicz University in Poznan Faculty of Chemistry Department of Water and Soil Analysis 61-614 Poznan Poland

The research presents the first results of aluminium speciation analysis in aqueous extracts of individual plant parts of Betula pendula and soil samples, using High Performance Ion Chromatography with Diode Array Detection（HPIC-DAD）. The applied method allowed us to carry out a full speciation analysis of aluminium in the form of predominant aluminium–fluoride complexes： AlF（（x = 2,3,4））^（（3-x））（first analytical signal）, AlF^（2＋）（second analytical signal） and Al^（3＋）（third analytical signal） in samples of lateral roots, tap roots, twigs, stem, leaf and soil collected under roots of B. pendula. Concentrations of aluminium and its complexes were determined for two types of environment characterised by different degree of human impact：contaminated site of the Chemical Plant in Luboń and protected area of the Wielkopolski National Park. For all the analysed samples of B. pendula and soil, AlF（（x = 2,3,4））^（（3-x））had the largest contribution, followed by Al^（3＋）and AlF^（2＋）. Significant differences in concentration and contribution of Al–F complexes and Al^（3＋）form, depending on the place of sampling（different anthropogenic pressure） and plant part of B. pendula were observed. Based on the obtained results, it was found that transport of aluminium is ＂blocked＂ by lateral roots, and is closely related to Al content of soil.

关键词： aluminium aluminium-fluoride complexes Soil Betula pendula Plant parts Speciation analysis

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Effects of Trace Cl^(-),Cu^(2+)and Fe^(3+) Ions on the Corrosion Behaviour of AA6063 in Ethylene Glycol and Water Solutions

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Acta Metallurgica Sinica(English Letters) 2022年第2期35卷 285-303页

作者： Lei Fan Juantao Zhang Hao Wang Yang Liu Yu Cui Cheng Wang Rui Liu Dongxiao Xu State Key Laboratory for Performance and Structure Safety of Petroleum Tubular Goods and Equipment Materials CNPC Tubular Goods Research InstituteXi’an 710077China NO.1 Gas Production Plant of Changqing Oilfield Company Jingbian 718500China Shi-Changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Shenyang National Laboratory for Materials Science School of Materials Science and EngineeringNortheastern UniversityShenyang 110819China

The effects of Cl^(-),Cu^(2+)and Fe^(3+)ions and their combinations on the corrosion behaviour of aluminium alloy 6063(AA6063)in ethylene glycol and water solutions at 50°C were investigated by electrochemical and immersion methods.Cl^(-)resulted in pitting corrosion of the alloy.In the Cl^(-)-free solutions,Fe^(3+)was prone to accelerate uniform corrosion,while Cu^(2+)tended to accelerate pitting corrosion.Severe pitting corrosion of AA6063 was observed in the cases of Cl^(-)combined with Cu^(2+)or Fe^(3+),especially in the case of Cl^(-)combined with Cu^(2+)and Fe^(3+)ions.

关键词： aluminium Polarization Weight loss Pitting corrosion

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Separation of aluminum from rare earth by solvent extraction with 4-octyloxybenzoic acid

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Journal of Rare Earths 2023年第2期41卷 290-299页

作者： Gaoshan Yu Zhiyuan Zeng Yun Gao Shuainan Ni Hepeng Zhang Xiaoqi Sun CAS Key Laboratory of Design and Assembly of Functional Nanostructures Fujian Key Laboratory of NanomaterialsFujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China Fujian Research Center for Rare Earth Engineering Technology Xiamen Institute of Rare Earth MaterialsHaixi InstituteChinese Academy of SciencesXiamen 361021China University of Chinese Academy of Sciences Beijing 100039China Jiangxi Province Key Laboratory of Cleaner Production of Rare Earths Ganjiang Innovation AcademyChinese Academy of SciencesGanzhou 341000China

Leaching method is usually used to extract rare earth(RE)elements from ion adsorbed RE ores.In the leaching process,some impurities such as aluminum(Al)enter the leaching solution.The separation of Al from RE by carboxylic acid extractant 4-octyloxybenzoic acid(POOA)was studied in this article.By changing the pH value,temperature,solvent,saponification degree and other parameters,the extraction and separation performance of POOA in chloride system was systematically studied.Through specific extraction experiments and slope analysis,it can be seen that the stoichiometric ratio of POOA to Al is 3:1during the extraction process.The separation factor of Al^(3+)and Pr^(3+)can reach about 160.00.Compared with easily emulsified naphthenic acid,POOA achieves better phase separation.The above results show that saponified POOA(S-POOA)has a good separation effect on Al and RE.Under the condition of low concentration stripping acid of 0.60 mol/L HCl,the developed extraction system can be almost completely stripped,and the stripping rate reaches 97.52%.The regenerated POOA can be directly used for the recycling extraction.

关键词： Rare earths aluminium 4-octyoxybenzoic acid Solvent extraction Separation

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aluminium in compacted graphite iron

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China Foundry 2020年第2期17卷 137-143页

作者： Grzegorz Gumienny Barbara Kurowska Leszek Klimek Lodz University of Technology Department of Materials Engineering and Production SystemsStefanowskiego 1/1590-924.ód.Poland Lodz University of Technology Department of Materials EngineeringStefanowskiego 1/1590-924.ód.Poland

Compacted graphite was obtained using inmold technology.The effect of aluminium on the crystallization process,microstructure,ferrite microhardness,and hardness of compacted graphite iron was studied.The microscopic and diffraction tests were also performed,and the process of cast iron crystallization was also investigated.Results show that aluminium increases the temperature of the eutectic transformation as well as the transformation temperature in the solid state.It is found that aluminium is a graphite forming element in compacted graphite iron(CGI)at a concentration up to 2.4wt.%.When its concentration is higher than 3.1wt.%,aluminium causes the spheroidization of the carbides in eutectoid mixture.It is also demonstrated that in cast iron with an aluminium content higher than^8wt.%,AlFe3C(0.5)phase crystallizes from the liquid.

关键词： compacted graphite iron aluminium cooling curves

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Effect of silicon carbide and wire-mesh reinforcements in dissimilar grade aluminium explosive clad composites

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Defence Technology（防务技术） 2020年第6期16卷 1160-1166页

作者： S.Saravanan K.Raghukandan Department of Mechanical Engineering Annamalai UniversityAnnamalainagarTamilnaduIndia Department of Manufacturing Engineering Annamalai UniversityAnnamalainagarTamilnaduIndia

aluminium composites are inevitable in the manufacture of aircraft structural elements owing to less weight,superior corrosion resistance and higher specific properties.These composites reduce the weight of the aircraft,improve the fuel efficiency and enhance the maintenance duration.This study proposes the development of dissimilar grade aluminium(aluminium 1100-aluminium 5052)composites with different reinforcement’s viz.,stainless steel wire-mesh,silicon carbide(SiC)powders and SiC powder interspersed wire-mesh,by explosive cladding technique.Wire-mesh enhances the friction and restricts the movement of flyer plate to craft a defect free clad,while SiC particles form a band on the interface.Highest strength is obtained when SiC powder interspersed wire mesh is employed as reinforcement.The dissimilar aluminium explosive clad with SiC particle reinforcement results in lower strength,which is higher than that of the weaker parent alloy and that of the conventional dissimilar aluminium explosive clads without any reinforcement.

关键词： Explosive cladding aluminium Wire mesh Silicon carbide Microstructure Strength

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Optimizing the micro-arc oxidation (MAO) parameters to attain coatings with minimum porosity and maximum hardness on the friction stir welded AA6061 aluminium alloy welds

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Defence Technology（防务技术） 2017年第2期13卷 111-117页

作者： R. Kamal Jayaraj S. Malarvizhi V. Balasubramanian Centre for Materials Joining and Research(CEMAJOR) Department of Manufacturing EngineeringAnnamalai UniversityAnnamalai Nagar608 002Tamil NaduIndia

Micro-arc oxidation(MAO) technique is capable of producing dense oxide films on the aluminium alloy surface. This oxide film protects the aluminium alloy from the corrosion attack for longer duration.Empirical relationships were derived to evaluate the MAO coating properties(porosity and hardness) by incorporating very important MAO parameters(current density, inter-electrode distance and oxidation time). MAO parameters were also optimized to achieve coatings with minimum porosity and maximum hardness. Further, the effect of MAO parameters on coating characteristics was analysed. From the results, it is found that the current density has greater influence on the responses than the other two parameters.

关键词： Micro-arc oxidation aluminium alloy Friction stir weld Response surface methodology

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Microstructural characterization of silicon carbide reinforced dissimilar grade aluminium explosive clads

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Defence Technology（防务技术） 2020年第3期16卷 689-694页

作者： S.Saravanan H.Inokawa R.Tomoshige K.Raghukandan Research Centre for Advances in Impact Engineering Sojo UniversityKumamotoJapan Department of Mechanical Engineering Annamalai UniversityTamilnaduIndia Department of Nanoscience Sojo UniversityKumamotoJapan Department of Manufacturing Engineering Annamalai UniversityTamilnaduIndia

aluminium composites are inevitable in ship building,commercial and defence aircrafts construction due to their light weight,high strength to weight ratio,admirable properties and cost affordability.In this study,the microstructural characteristics of explosive cladded dissimilar grade aluminium(Al 1100-Al 5052) clad composites reinforced with silicon carbide(SiC) particles is presented.Microstructure taken at the interface by optical and scanning electron microscopes(SEM) revealed the formation of a silicon carbide layer between the dissimilar grade aluminium sheets.Though reaction layers were witnessed at few locations along the interface,the diffusion of atoms between the participant metals is not visible as confirmed by energy dispersive spectroscopy,elemental mapping,line analysis and X-ray diffraction(XRD).The variation in microhardness at various regions of the silicon carbide reinforced dissimilar aluminium explosive clad is reported.The increase in tensile strength of the SiC laced clad is also presented.

关键词： Explosive cladding aluminium Silicon carbide Microstructure Elemental mapping Hardness

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High-temperature mechanical properties of aluminium alloys reinforced with titanium diboride (TiB_2) particles

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Rare Metals 2011年第2期30卷 200-205页

作者： J.Ooro Ingeniería y Ciencia de los Materiales ETSI IndustrialesUniversidad Politécnica de Madridc/José Gutiérrez Abascal2.28006 MadridSpain

The physical and mechanical properties of metal matrix composites were improved by the addition of reinforcements. The mechanical properties of particulate-reinforced metal-matrix composites based on aluminium alloys （6061 and 7015） at high temperatures were studied. Titanium diboride （TiB2） particles were used as the reinforcement. All the composites were produced by hot extrusion. The tensile properties and fracture characteristics of these materials were investigated at room temperature and at high temperatures to determine their ultimate strength and strain to failure. The fracture surface was analysed by scanning electron microscopy. TiB2 particles provide high stability of the alumin- ium alloys （6061 and 7015） in the fabrication process. An improvement in the mechanical behaviour was achieved by adding TiB2 particles as reinforcement in both the aluminium alloys. Adding TiB2 particles reduces the ductility of the aluminium alloys but does not change the microscopic mode of failure, and the fracture surface exhibits a ductile appearance with dimples formed by coalescence.

关键词： metal-matrix composites aluminium high-temperature properties titanium diboride

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High temperature tribological behaviour of PVD coated tool steel and aluminium under dry and lubricated conditions

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Friction 2021年第4期9卷 802-821页

作者： Justine DECROZANT-TRIQUENAUX Leonardo PELCASTRE Cedric COURBON Braham PRAKASH Jens HARDELL Division of Machine Elements Lulea University of TechnologySE-97187Sweden Universite de Lyon CNRSEcole Nationale d'lngenieurs de Saint-EtienneLTDS UMR5513F-42023France Department of Mechanical Engineering Tsinghua UniversityBeijing100084 China

aluminium alloys are commonly used as lightweight materials in the automotive industry.This non-ferrous family of metallic alloys offers a high versatility of properties and designs.To reduce weight and improve safety,high strength-to-weight ratio alloys(e.g.6XXX and 7XXX),are increasingly implemented in vehicles.However,these alloys exhibit low formability and experience considerable springback during cold forming,and are therefore hot formed.During forming,severe adhesion(i.***.galling)of aluminium onto the die surface takes place.This phenomenon has a detrimental effect on the surface properties,geometrical tolerances of the formed parts and maintenance of the dies.The effect of surface engineering as well as lubricant chemistry on galling has not been sufficiently investigated.Diamond-like carbon(DLC)and CrN physical vapour deposition(PVD)coated steel have been studied to reduce aluminium transfer.However,the interaction between lubricants and PVD coatings during hot forming of aluminium alloys is not yet fully understood.The present study thus aims to characterise the high temperature tribological behaviour of selected PVD coatings and lubricants during sliding against aluminium alloy.The objectives are to first select promising lubricant-coating combinations and then to study their tribological response in a high-temperature reciprocating friction and wear tester.Dry and lubricated tests were carried out at 300℃ using a commercial polymer lubricant.Tests using DLC,CrN,CrTiN,and CrAIN coated tool steel were compared to uncoated tool steel reference tests.The initial and worn test specimen surfaces were analysed with a 3-dimensional(3D)optical profiler,scanning electron microscope(SEM)and energy dispersive X-ray spectroscope(EDS)as to understand the wear mechanisms.The results showed formation of tribolayers in the contact zone,reducing both friction and wear.The stability of these layers highly depends on both the coatings'roughness and chemical affinity towards aluminium.The DLC and CrN coatings combined with

关键词： high temperature tribology aluminium lubrication physical vapour deposition(PVD)coatings material transfer adhesion

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