緻密化動力學 的英文怎麼說
中文拼音 [zhìmìhuàdònglìxué]
緻密化動力學
英文
densification kinetics-
Topics include : planets, planet formation ; stars, the sun, " normal " stars, star formation ; stellar evolution, supernovae, compact objects ( white dwarfs, neutron stars, and black holes ), plusars, binary x - ray sources ; star clusters, globular and open clusters ; interstellar medium, gas, dust, magnetic fields, cosmic rays ; distance ladder ; galaxies, normal and active galaxies, jets ; gravitational lensing ; large scaling structure ; newtonian cosmology, dynamical expansion and thermal history of the universe ; cosmic microwave background radiation ; big - bang nucleosynthesis
課程的主題包含了：行星、行星形成；恆星、太陽、正常的恆星、恆星形成；恆星演化、超新星、緻密天體（白矮星、中子星及黑洞） 、波霎、雙x -射線源；星團、球狀及疏散星團；星際介質、氣體、塵埃、磁場、宇宙射線；距離階梯；星系、正常及活躍星系、噴流；重力透鏡；大尺度結構；牛頓宇宙學、宇宙的動力膨脹及溫度發展歷史；宇宙背景微波輻射；大霹靂核合成。The experimental data has been used to validate pdm and low temperature sintering mechanics. the advantage and disadvantage of pdm have been discussed also. for the first time, the pdm is used to study the low temperature sintering mechanics of uo _ 2, and the research results indicate : 1
3 、基於燒結頸長大速率與緻密化動力學方程得出，影響二氧化鈾低溫燒結的因素有原始粉末粒徑、粉末堆積方式、坯塊原始密度、燒結溫度、燒結時間、燒結氣氛等;粉末壓坯一定時，燒結溫度、燒結時間和燒結氣氛就成為控制低溫燒結的關鍵因素。Microstructure of the composite layer was analyzed with help of optical microscope, scanning electronic microscope ( sem ), electronic probe microanalysis ( epma ) and x - ray diffraction ( xrd ). the compacting of the billet and the forming mechanism of the carbide reinforcement were studied based on thermodynamics and kinetics of reaction, sintering theory and the result of dta. at the same time, the wear - resistance of the composite layer was studied under condition of dry sliding friction
利用光學顯微鏡、掃描電子顯微鏡、電子探針以及x -射線衍射儀，分析了表面復合層的基體組織結構；運用反應熱力學、動力學、粉末燒結理論和燃燒合成理論，結合差熱分析結果，探討了表面復合層壓坯的燒結緻密化原理和碳化物增強相的形成機理；利用坯塊在真空燒結爐不同溫度下的燒結出來的顯微組織分析，模擬出坯塊的燒結過程中的化學反應過程。The influence of nano - al2o3 on the sintering and the properties of the si3n4 ceramics was researched in this paper. the samples with different amount of nano - al2o3 were obtained by using pressureless sintering at 1600, 1650, 1700 in the nitrogen atmosphere. the microstructure and the composition of the ceramics were determined by the means of x - ray, sem, micro - hardness meter etc. it is show that the sisty ceramics can be densified at 1650c to % percent of the theory density through the addition of nano - al2o3 ( the value could be 90 percent by other technique ). the crystalline growth of the cylindrical - si3n4 and the ratio of its longitude to its diameter are increased with the addition of nano - al2o3. a uniform microstructure and an fined crystal as well as more sialon phases can be obtained in the si3n4 ceramics through the addition of that
實驗結果表明：在碳管爐中、氮氣保護下進行燒結，添加劑為納米al _ 2o _ 3粉末時，由於納米粉末的高活性、高燒結驅動力，在1650就可使si _ 3n _ 4完全地燒結，並使其緻密度可達理論密度的96以上（比其它工藝高6左右） ；同時，納米al _ 2o _ 3地加入大大促進了長柱狀? si _ 3n _ 4的生長和發育及柱狀晶長徑比的提高，使微觀結構均勻、細化，形成了更多力學性能優異的固體? sialon相，減少了不利於陶瓷材料性能的晶間玻璃相，凈化了晶界。分享友人