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Effect of processing temperatures on characteristics of surface layers of low temperature plasma nitrocarburized AISI 204Cu austenitic stainless steel

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中国有色金属学会会刊：英文版 2012年第S3期22卷 678-682页

作者： Insup LEE Department of Advanced Materials Engineering Dongeui University

The influence of processing temperatures on the surface characteristics of AISI 204Cu austenitic stainless steel was investigated during a low temperature plasma *** resultant layer was a dual-layer structure,which comprises a N-enriched layer on the top of C-enriched *** surface hardness.and the layer thickness increase up to about HV 0.05 1000 and 20μm with increasing *** specimen treated at 400°C shows a much enhanced corrosion resistance compared to the untreated steel.A loss in corrosion resistance was observed for specimens treated at temperatures above 430°C due to the formation of Cr2N.

关键词： low temperature plasma nitrocarburizing corrosion resistance expanded austenite AISI 204Cu stainless steel hardness.

MD simulation of the effect of contact area and tip radius on nanoindentation

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Science China(Physics,Mechanics & Astronomy) 2004年第1期47卷 101-112页

作者： CHEN Shangda1,2 & KE Fujiu1,2 1. Department of Applied Physics, Beijing University of Aeronautics and Astronautics, Beijing 100083, China 2. State Key Laboratory of Non-linear Mechanics (LNM), Institute of Mechanics, Chinese Academy of Sciences, Beijing 100080, China Correspondence should be addressed to Chen Shangda (email: chensd@***) Received August 27, 2003 1. Department of Applied Physics Beijing University of Aeronautics and Astronautics 100083 Beijing China 2. State Key Laboratory of Non-linear Mechanics (LNM) Institute of Mechanics Chinese Academy of Sciences 100080 Beijing China

Molecular dynamics simulations of nanoindentation are performed on monocrystal copper. A new contact atoms method is presented for calculating the contact area. Compared with conventional methods, this method can provide the contact area more accurately not only for sink-in but also for pile-up situation. The effect of tip radius on indentation is investigated too. The results indicate that the measured hardness.of the material will become higher as the tip radius increases.

关键词： nanoindentation, molecular dynamics, contact area, zero point of penetration depth, nano- hardness.

Formation of new Zr-Ti-Cu-Ni-Be-C bulk amorphous alloy

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Science China Mathematics 1998年第7期41卷 756-760页

作者：汪卫华王文魁白海洋 1. Institute of Physics Chinese Academy of Sciences 100080 Beijing China 2. Cryogenic Laboratory Chinese Academy of Sciences 100080 Beijing China

The formation of the new bulk amorphous Zr Ti Cu Ni Be C alloy with high strength is reported. The effects of the small size atoms on the glass forming ability, strength and thermal stability of the amorphous alloy ar... 详细信息

关键词： bulk amorphous alloy glass forming ability Zr Ti Cu Ni Be C alloy hardness.

Impact of blanching pretreatment on the drying rate and energy consumption during far-infrared drying of Paprika(Capsicum annuum L.)

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Food Quality and Safety 2018年第2期2卷 97-103页

作者： Takahiro Orikasa Naoki Ono Takashi Watanabe Yasumasa Ando Takeo Shiina Shoji Koide Faculty of Agriculture Iwate UniversityMorioka IARC Kenpoku Agricultural Research Institute KunoheIwate Food Research Institute NAROTsukubaIbaraki Graduate School of Horticulture Chiba UniversityMatsudoJapan

We incorporated a superheated steam blanching pretreatment step into a paprika drying process and compared the far-infrared(FIR)drying rates,hardness.of the sample surfaces,cell membrane stabilities,and energy consumption of blanched and non-blanched *** average drying rate of blanched paprika samples during FIR drying was higher than that of non-blanched *** hardness.and cell membrane stability of dried blanched samples were lower than those of non-blanched *** estimated that the softening of the sample surfaces and injury to the cell membranes caused the drying rate to *** total energy consumption of the FIR drying of paprika was reduced by approximately 30%by introducing the blanching *** findings contribute to the development of environmentally friendly FIR drying techniques for paprika.

关键词： blanching cell membrane stability,energy consumption far-infrared drying hardness.

The Laser Transformation Hardening Mechanism of High Speed Steel W_6Mo_5Cr_4V_2

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Chinese Science Bulletin 1994年第3期39卷 253-257页

作者：刘宁邓宗钢胡镇华崔昆孔捷程本培 Department of Mechanical Engineering No. 2 Huazhony University of Science and Technology Wuhan 430074 PRC Institute of Solid State Physics. Academia Sinica Hefei 230031 PRC

The application of laser surface melting in the laser heat treatment of high speedsteel causes low hardness. so the subsequent quenching and tempering processesare needed. And by means of transformation hardening techniques, ultrahighhardness.>HV1000 can be *** this case, the subsequent quenching pro-cess can be saved, and the wear and scuffing resistances can be considerably im-proved. However, the laser transformation hardening mechanism has not beenunderstood clearly. The laser transformation hardening mechanism of high speedsteel W6Mo5Cr4V2 has been studied in the present note by TEM and X-ray diffractionmethod in order to provide a theoretical basis for application.

关键词： high speed steel W6 MosCr4V2 laser heat treatment transformation hardening mechanism ultrahigh hardness.

Optimum Calcium Carbonate Filler Concentration for Flexible Polyurethane Foam Composite

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Journal of Minerals and Materials Characterization and Engineering 2012年第3期11卷 311-320页

作者： M. A. Usman S. O. Adeosun G. O. Osifeso Department of Chemical Engineering University of Lagos Akoka –Yaba Lagos Nigeria. Department of Chemical Engineering University of Lagos Akoka –Yaba Lagos Nigeria. Department of Metallurgical and Materials Engineering University of Lagos Akoka –Yaba Lagos Nigeria.

The production cost of flexible polyurethane foam is significantly dependent on the cost of polyol, which constitute the largest percentage of materials used in foam production with the characteracterics to induce superior mechanical properties. Suitable fillers that are relatively cheap can be introduced in the foam matrix as replacement for polyol. However, certain compositions of filler have deleterious effect on some relevant mechanical properties of the foam. This paper investigates the effect of CaCO3 filler in flexible polyurethane foam matrix for the dual purposes of achieving sustained mechanical properties and reduction in production cost. The optimum CaCO3 composition was found to be 20 wt % representing a concomitant 18.54% reduction in cost of production.

关键词： polyurethane CaCO3 tensile strength elongation at break indentation hardness.

Structural and Optical Properties of Triglycine Sulfate Single Crystals Doped with Potassium Bromide

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Journal of Crystallization Process and Technology 2011年第2期1卷 26-31页

作者： Farhana Khanum Jiban Podder Deprtment of Physics Bangladesh University of Engineering and Technology Dhaka-1000

Triglycine sulfate crystal and potassium bromide doped triglycine sulfate crystals were grown from aqueous solution by slow evaporation method. Energy dispersive X-ray analysis identifies the elements present in the crystal. The Fourier Transform Infrared spectroscopy has been recorded in the range 400 to 4000 cm-1 and the functional groups of the grown crystals have been identified. The structural studies on the grown crystals were carried out by X-ray diffraction analysis technique and found that the grown crystal crystallizes in monoclinic structure. The lattice cell parameters of pure Triglycine sulfate are a = 9.6010 ?, b = 12.5600 ?, c = 5.4500 ?. Ultraviolet-Visible spectra show that the grown crystals have wide optical transparency in the entire visible region.

关键词： Crystal Growth Triglycine Sulfate X-Ray Diffraction Bang Gap Vicker’s Micro hardness.

Influence of Purity Degree on the Evolution the Mechanical Properties of Aluminium Commercial

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Journal of Chemistry and Chemical Engineering 2012年第10期6卷 920-924页

作者： Ahmed Hakem Y. Bouafia Laboratory LaMoMS Mouloud MAMMERI University of Tizi-Ouzou Hasnaoua II 15000 Algeria

The influence of the purity degree of the commercial aluminium on the mechanical properties： elastic stress, tensile strength, Brinell hardness. resilience and elongation at break was investigated. It was found that the first three resistance characteristics decrease with the growth of the purity of the material chosen to the detriment of two ductility characteristics that rise to the three states considered： crude of casting noted： F, Annealed noted： O, hardened noted ： H1/4. Furthermore, it is important to note that the hardened and the annealed lead respectively to a considerable hardening and a considerable softening. This hardening and this softening of the material in question can be respectively associated with the increase in dislocation density and immigration impurity elements of dislocations.

关键词： Purity aluminum properties mechanical hardness.

Effect of Heat Treatment on Microstructure and Properties of Cu-3Ti-1Al Alloy

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Effect of Heat Treatment on Microstructure and Properties of...