英文板模拟国际会议--PPT

1、LOGO19th XXXXXXXConferenceDecember 26, 2016 Shenyang, ChinaSponsor ：Northeastern UniversityOrganizer：School of materials science and EngineeringSurface Science and Engineering for Industry in Future8 : 30 8 : 50 registration8 : 50 9 : 10 Opening ceremonyWelcome speechPro. M L9 : 10 11 :10Keynote spe

2、echesANitriding iron at lower temperaturesPro. P L11 : 10 14 : 10 Lunch14 : 10 16 : 10 Keynote speeches BPorous mullite ceramics with low thermal conductivity prepared by foaming and starch consolidationPro. Y D16 : 10 16 : 30 Closing ceremonyClosing remarksPro. X C19th XXXXXXXConferenceOpening cere

3、monyDecember 26, 2016 Shenyang, ChinaSponsor ：Northeastern UniversityOrganizer：School of materials science and EKeynote speeches AXXXXXXXXXXXXXXXDr. P LContentsIntroduction1Experiment2Results and discussion3 3Conclusions4 4Group Chemical treatmentHard surface and tough interiorMechanical performance

4、 and wear/corrosion resistanceNitriding processes500 for long duration(2080 hours)IntroductionGroup 3ExperimentGroup 3Surface microstructureChemical reactionGrain boundariesTwo iron plates (7*100*100mm)with a purity of 99.95 weight percent(wt%) One was treated by SMAT, another one not.Both the untre

5、ated and treated samples were nitrided in flowing, high-purity ammonia gas(NH3) at 300 for 9 hoursResults and discussionGroup 3Fig. 1.cross-sectional observations of (A)an original coarse grained Fe sample(B)a SMAT Fe sample after nitriding at 300 for 9 hours(c)Nitrogen concentration (D)microhardnes

6、s along the depth from the top surface layer in the original Fe sampleResults and discussionGroup 3Fig.2.(A)a dark-field TEM image (B)the corresponding electron diffraction pattern for the compound layer (C)A TEM image for the microstructure beneath the compound layer (D)An XRD for the SMAT Fe sampl

7、e and the original sampleConclusionsGroup 3Similarly, other surface chemical treatments that are controlled by the diffusion of foreign atoms and are used in industry to improve the performance of engineering materials can be also be enhanced by SMAT. We found a greatly enhanced diffusively of chrom

8、ium in the SMAT Fe at 350 ,which is about 300 to 400 lower than the conventional treatment temperatureThis enhance processing method demonstrates the technological significance of nanomaterials in improving traditional processing techniques and provides a new approach for selective surface reactions

9、 in solids. Company LogoKeynote speeches BXXXXXXXXXXXXXDr. Y DContentsIntroductionExperimentalResults and discussionIntroductionlow bulk density、low thermal conductivity（less than 0.2W/mK）、heat resistance、high porosity and high surface arealeaching method、gelcasting、reaction-bonding technique、starch

10、 consolidation method、gel freeze drying and foam-gelcastingPropertymolding methodExperimental Materials Preparation processinglAn industrial grade fused mullite powderlCristobalite（SiO2）lSodium carboxymethyl cellulose （CMC)lSodium dodecyl sulfate(SDS)Mullite powder, cornstarch, CMC, distilled water

11、and dispersantSinteringBall milling 20 minFoaming suspensionConsolidation (75 for 1h)Foaming of suspensionsResults and discussionMicro-structurePorosityFoaming of suspensions Higher solid loading results in larger viscosity and lower foaming volume Viscosity of the foamed suspension is much higher t

12、han the original one at low rotational speed. PorosityWhen the temperature increased ，the porosity decreasedAt the same sintering temperaturelow solid loading sample has a higher porosity.Microstructure The two samples exhibit almost a same pore morphology which is a typical result of direct foaming

13、 method . It can also be found that higher porosity sample contains more large pores than lower one. The result indicates that the porous mullite ceramics prepared by this method exhibit a similar pore morphology and contain more large pores with higher porosity.62.5wt%67.5wt%ConclusionsThe porosity

14、 of porous mullite ceramics can be varied from 73 to 86 vol% by adjusting solid loading of suspension and sintering temperature.Porous mullite ceramics comprised a hierarchical microstructure of large spherical pores and small pores on internal walls, and possessed a larger average pore size with higher porosity.These samples prepared by foaming and starch consolidation have low thermal conductivity and meanwhile keep suitable mechanical strength.19th XXXXXXXConferenceClosing ceremonyDecember 26, 2