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PROPERTIES, WEldABIlITY ANd APPlICATIONS OF AdVANCEd WROUGHT SUPERAllOYS FOR GAS TURBINE ENGINES

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Acta Metallurgica Sinica(English letters) 2005年第1期18卷 1-14页

作者： d.l. Klarstrom V.R. Ishwar M.d. Rowe Haynes International Inc. Kokomo Indiana IN 46904-9013 USAHaynes International Inc. Kokomo Indiana IN 46904-9013 USAHaynes International Inc. Kokomo Indiana IN 46904-9013 USA

Alloy selection and alloy design both require consideration of an array of material attributes, including in-service properties, weldability and fabricability. Critical properties of advanced wrought superalloys for gas turbine applications include high temperature strength, thermal stability, oxidation resistance and fatigue resistance. In this paper, the properties of twelve wrought solid-solution-strengthened and six age-hardenable superalloys are compared. Weldability is an important attribute and can be a major limiting factor in the use of certain alloys. Weldability test methods are discussed and the resistance of alloys to solidification cracking and strain-age cracking is compared. The use of weldability testing in the development of modern wrought su-peralloys is discussed with several examples cited. Finally, alloy selection for gas turbine components is outlined, taking into account both alloy properties and fabricability.

关键词： wrought superalloys mechanical properties strain-age cracking of weldments selection and application of wrought superalloys

ElECTRONIC STRUCTURE OF THE laNi_(5-x)Ga_x INTERMETAllIC COMPOUNdS

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Acta Metallurgica Sinica(English letters) 2008年第3期21卷 157-162页

作者： d. Chen G.X. li d.l. Zhang T. Gao department of Physics and Electronic Engineering Xinyang Normal University Xinyang 464000 China College of Science Qingdao Agriculture University Qingdao 266109 China Institute of Atomic and Molecular Physics Sichuan University Chengdu 610065 China

The equilibrium structures and electronic structure of laNi5-xGax （x=0, 0.5, 1.0） compounds have been investigated by all-electron calculations. Based on the full geometry optimization, the densities of states and electron densities of laNi5-xGax are plotted and analyzed. It is clear that the substitution of Ga at the Ni site leads to a progressive filling of the Ni-d bands, the ionic interaction between Ni and Ni, with Ga plays a dominant role in the stability of laNi5-xGax compounds. The smaller the shift of EF toward higher energy region, the more stable the compounds will be. The increased contribution of the Ni-d-Ga-d interactions near EF and the low energy metal-gallium bonding bands indicate that the compounds become more stable. The results are compared with experimental data and discussed in light of previous studies.

关键词： FlAPW and GGA laNi5-xGax Intermetallie compound Electronic structure

Strengthening mechanisms in magnesium alloys containing ternary Ⅰ,W and.l.SO phases

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Journal of Materials Science & Technology 2018年第7期34卷 1110-1118页

作者： N.Tahreen d.F. Zhang F.S. Pan X.Q. Jiang d.Y. li d.l. Chen department of Mechanical and Industrial Engineering Ryerson University Toronto Ontario MSB 2K3 Canada College of Materials Science and Engineering Chongqing University Chongqing 400045 China National Engineering Research Center for Magnesium Alloys Chongqing University Chongqing 400044 China Advanced Materials Research Center ChongqingAcademy of Science and Technology Chongqing 401123 China Faculty of Materials and Energy Southwest University Chongqing 400715 China department of Chemical and Materials Engineering University of Alberta Alberta T6G 11-19 Canada

This study was aimed at identifying underlying strengthening mechanisms and predicting the yield strength of as-extruded Mg-Zn-Y alloys with varying amounts of yttrium （Y） element. The addition of Y resulted in the formation of ternary 1 （Mg3YZn6）, W （Mg3Y2Zn3） and.l.SO （Mg12YZn） phases which subse- quently reinforced alloys ZM31 ＋ 0.3Y, ZM31 ＋ 3.2Y and ZM31 ＋ 6Y, where the value denoted the amount of Y element （in wt%）. Yield strength of the alloys was determined via uniaxial compression testing, and grain size and second-phase particles were characterized using OM and SEM. In-situ high-temperature XRd was performed to determine the coefficient of thermal expansion （CTE）, which was derived to be 1.38 x 10^-5 K^-1 and 2.35 x 10^-5 K^-1 for W and.l.SO phases, respectively. The individual strengthening effects in each material were quantified for the first time, including grain refinement, Orowan looping, thermal mismatch, dislocation density, load-bearing, and particle shearing contributions. Grain refinement was one of the major strengthening mechanisms and it was present in all the alloys studied, irrespective of the second-phase particles. Orowan looping and crE mismatch were the predominant strengthening mechanisms in the ZM31＋0.3Y and ZM31 ＋ 3.2Y alloys containing I and W phases, respectively, while load-bearing and second-phase shearing were the salient mechanisms contributing largely to the superior yield strength of the lPSO-reinforced ZM31 ＋ 6Y alloy.2017 Published by Elsevier ltd on behalf of The editorial office of Journal of Materials Science ＆ Technology.

关键词： Magnesium alloy I-phase W-phase lPSO phase Strengthening mechanism

An in-vitro Investigation of Iron-Containing Hydroxyapatite/Titanium Composites

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Journal of Materials Science & Technology 2011年第6期27卷 546-552页

作者： Q. Chang H.Q. Ru d.l. Chen X.Y. Yue l. Yu C.P. Zhang Key laboratory for Anisotropy and Texture of Materials (Ministry of Education) Northeastern University Shenyang 110004 China department of Mechanical and Industrial Engineering Ryerson University 350 Victoria Street Toronto Ontario M5B 2K3 Canada

The in-vitro biological behavior of a newly-developed iron-containing hydroxyapatite/titanium（HA/Ti） composite was investigated by immersing the composites in the simulated body fluid（SBF） for up to 5 *** addition of iron was observed to have a significant influence on the in-vitro biological behavior of the *** obtained results revealed that the stability of the composites in the physiological solution was markedly *** solubility decreased in the order of pure HA,HA/5（Ti-33Fe）,and HA/15（Ti33Fe）.Precipitation occurred on the surface of HA/5（Ti-33Fe） composite,showing a good combination of physiostability with bioactivity,while HA/15（Ti-33Fe） composite exhibited superior physiostability since there was no obvious change on the surface of HA/15（Ti-33Fe）.

关键词： Hydroxyapatite composite Iron Titanium Simulated body fluid Biological behavior

Spouting behavior of binary particle mixtures of different densities: Fluid dynamics and particle segregation

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Particuology 2019年第1期17卷 58-66页

作者： K.G. Santos R.C. Santana d.l. Souza V.V. Murata M.A.S. Barrozo Federal University ofTriangulo Mineiro Chemical Engineering DepartmentUniverdecidade CampusUberabaMGBrazil Federal University of Uberlandia Chemical Engineering SchoolUberlandiaMG. Brazil

Numerous industrial applications of spouted beds involve a mixture of granular particles, where differences in particle size, density, and shape can cause particle segregation, affecting the quality of flow and decreasing product homogeneity. The aim of this study was to investigate the particle segregation and fluid dynamics of a conical spouted bed operating with a binary mixture of particles of different densities. Using glass beads and polyethylene particles with a diameter of 4 mm, we determined the effects of the mass fraction of denser particles and static bed height on the minimum spouting condition and mixture index. The pressure drop and airflow in the minimum spouting condition increased with an increase in bed height or jetsam concentration. Regarding particle segregation, the jetsam particles tended to concentrate near the bottom, at the spout–annulus interface because they have a shorter trajectory than the lighter particles in the fountain region. Jetsam-rich mixtures with high initial static bed heights exhibited more efficient particle mixing, excluding those at the bottom of the bed.

关键词： density Segregation Spouted bed Binary mixtures

N'-{1-[(6-氯吡啶-3-基)甲基]-5-甲基-1H-1,2,3-三唑-4-甲酰基}-N'-叔丁基-N-取代苯甲酰肼的合成与杀虫活性

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有机化学 2010年第12期30卷 1925-1930页

作者： Khalema Thandiwe d.l. 石德清华中师范大学化学学院农药与化学生物学教育部重点实验室武汉430079

双酰肼化合物作为一类重要的昆虫生长调节剂,已广泛应用于农作物的保护中.为了发现新颖结构的高效、低毒双酰肼杀虫剂先导化合物,采用点击化学常用的1,2,3-三唑杂环将新烟碱杀虫剂的药效团2-氯-5-(氯甲基)吡啶引入到双酰肼分子骨架中,... 详细信息

双酰肼化合物作为一类重要的昆虫生长调节剂,已广泛应用于农作物的保护中.为了发现新颖结构的高效、低毒双酰肼杀虫剂先导化合物,采用点击化学常用的1,2,3-三唑杂环将新烟碱杀虫剂的药效团2-氯-5-(氯甲基)吡啶引入到双酰肼分子骨架中,设计并合成了9种未见文献报道的含双杂环结构的双酰肼目标化合物,其结构经IR,1HNMR,ESI-MS和元素分析测试技术确证.初步的生物活性测定结果表明,部分目标化合物在200mg/l质量浓度下对小菜蛾(Spodoptera exigua)和甜菜夜蛾(Plutella xylostella)表现出中等程度的杀虫活性;但所有目标化合物在200mg/l浓度下对蚕豆蚜虫(Aphis fabae)的杀虫活性均较弱..

关键词： 1-[(6-氯吡啶-3-基)甲基]-5-甲基-1H-1,2,3-三唑-4-甲酸双酰肼化合物杀虫活性

STUdY ON THE SiC_p./Al-AllOY COMPOSITE AUTOMOTIVE BRAKE ROTORS

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Acta Metallurgica Sinica(English letters) 2000年第4期13卷 974-980页

作者： ding, Z.l. Fan, Y.C. Qi, H.B. Ren, d.l. Guo, J.B. Jiang, Z.Q. Shijiazhuang Railway Inst Shijiazhuang China

The SiCp/Al-alloy composite front brake rotors designed for Shanghai Santana cars were prepared by semi-solid stirring+liquid forging process. The composite brake rotors were subjected to dynamometer tests on a SCHENCK brake testing system, referring to Tl110 standard of VOlKSWAGEN Co. The friction coefficient and thermal response during fade testing and the wear performance of the composite rotors were studied as the functions of various parameters such as braking pressures, initial speeds, initial temperatures, torque and decelerations, and were compared with those of conventional cast iron rotors. The results show that the properties of the composite rotors can achieve the requirements of commercial cast iron rotors. The results also show that the friction coefficients of the composite rotors under different braking conditions are within the deviation band specified by the Tl110 standard, and the temperature rise of composite rotors is lower than that of cast iron rotors at the end of each fade stop. The wear resistance of composite rotors is higher than that of cast iron rotors. The friction mechanism and wear mechanism were analyzed.

关键词： Brakes Friction Metallic matrix composites Rotors Silicon carbide Wear resistance

THElATTICE STRAIN CAUSEd BY ION IMPlANTATION

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Acta Metallurgica Sinica(English letters) 1999年第4期12卷 495-499页

作者： d.l. Ma and X.l. Mu departmentof Physics,liaoning University,Shenyang 110036 ,China

The propertiesof As+ implantedsilicon with anenergy160kev, differentdosesand anneal ing temperatures (500 700℃) were studied by means of x ray double crystaldiffraction( dCd) and ellipometricspectra ( ES) . Therockingcurvesof dCdweresimulated by multi layer mod.l.f dynamicaltheory,toobtainstrain distributionsasafunctionof depths. The1×1016 cm 2 annealed at600℃wasfoundthataepitaxiallayer wasformed . The ESresult provedtheseconclusions.

关键词： THElATTICE STRAIN CAUSEd BY ION IMPlANTATION

HYPERSINGUlAR INTEGRAl EQUATIONS FOR PERIOdIC ARRAYS OF PlANAR CRACKS IN A PERIOdICAllY-lAYEREd ANISOTROPIC ElASTIC SPACE UNdER ANTIPlANE SHEAR STRESS

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Acta Mathematica Scientia 1999年第3期19卷 343-355页

作者： W.T.Ang (Faculty of Engineering, Universiti Malaysia Sarawak, 94300 Kota Samarahan, Malaysia)d.l. Clements(department of Applied Mathematics, University of Ad.l.ide, SA5005, Australia) Faculty of Engineering Universiti Malaysia Sarawak 94300 Kota Samarahan Malaysia department of Applied Mathematics University of Adelaide SA5005 Australia

Hypersingular integral equations are derived for the problem of determining the antiplane shear stress around periodic arrays of planar cracks in a periodically-layered anisotropic elastic space. The unknown functions are directly related to the jump in the displacements across opposite crack faces. Once the integral equations are solved, crack parameters of interest, such as the clack tip stress intensity factors, may be read.l. *** some specific examples of the problem, the integral equations are solved numerically by using a collocation technique, in order to compute the relevant stress intensity factors.

关键词： Periodically-located cracks periodically-layered anisotropic material antiplane shear stress hypersingulal integral equations