最新色国产精品精品视频,中文字幕日韩一区二区不卡,亚洲有码转帖,夜夜躁日日躁狠狠久久av,中国凸偷窥xxxx自由视频

Abstract:研究了石墨(Gr)鋁界面反應(yīng)對Gr,碳化硅(SiC)混雜增強鋁基復合材料(Gr+SiC)Al摩擦磨損性能的影響。在630℃下對SiCAl和混雜復合材料分別加熱保溫了4,8,12,16h。硬度試驗和透射電鏡分析說明,隨熱處理時間的延長,GrAl界面反應(yīng)物增加,而SiCAl幾乎沒有發(fā)生界面反應(yīng)。用熱處理后的混雜復合材料試樣進行了干磨損試驗。結(jié)果表明,隨著熱處理時間的延長,混雜復合材料摩擦系數(shù)升高,而磨損率降低。對Al4C3對復合材料摩擦磨損性能的影響進行了討論。

Abstract:研究了不同后處理(Ar,O2)對在空氣中制備的“粉末熔化處理法”(PMP)Nd123超導性能的影響。結(jié)果顯示,先進行高溫氬氣處理可以增加Nd123在隨后氧處理過程中的吸氧量,并使其ΔT變窄,Jc升高。低溫氧氣處理有一溫限Tlim,高于或太低于此溫限均不能有效地增加PMPNd123的氧含量;此溫限大約在600℃附近。

Abstract:The physical phenomena of solidification and the mechanical properties of aluminum matrix composites are reviewed.Nucleation and growth of the matrix, solute distribution and fluid flow in the cast aluminum matrix composites are changed by the addition of reinforcers, especially in the case of nonequilibrium solidification under differential pressure and under variation of the cooling conditions. Such changes greatly influence the dendrite structure of matrix, precipitation, solute segregation, interface reactivity, solidification defects etc., and properties of the composites.

Abstract:用熱重法研究了５種鑄態(tài)ＴｉＡｌ在靜止空氣中的高溫（７００℃～１０００℃）斷續(xù)氧化行為。ＴｉＡｌ在７００℃，１００ｈ戲微。８００℃，１００ｈ～１０００℃，１００ｈ氧化動力學曲線可用冪函數(shù)△Ｍ＾ｎ＝ｋｎｔ描述，通常１〈ｎ〈２，這表明。ＴｉＡｌ的斷續(xù)氧化規(guī)律一般介于線性規(guī)律與拋物線規(guī)律之間。中、高溫（≤９００℃）氧化時，合金成份對ＴｉＡｌ的氧化行為影響顯著，但隨著氧化溫度進一步增主，不同ＴｉＡｌ基合金間

Abstract:著重研究了采用真空離心噴射沉積成形的Ｔｉ－４８Ａｌ－２Ｍｎ－２Ｎｂ金屬間化合物及輕熱等靜壓處理的合金樣品的室溫斷裂韌度。采用三點彎曲試驗方法進行測試，結(jié)果表明，噴射沉積合金樣品的平均斷裂韌度值為２３．６ＭＰａｍ１／２，最大值約２８ＭＰａｍ１／２，而經(jīng)熱等靜壓后樣品的平均斷裂韌度僅為１５．３ＭＰａｍ１／２。結(jié)果分析認為，導狀組織對裂紋擴展的抗力比γ等軸晶的抗力高得多，因而經(jīng)熱等靜壓高得多，因而，具有

Abstract:采用金相、Ｘ射線衍射（ＸＲＤ）、透射電鏡（ＴＥＭ）、硬度測定和拉伸試驗研究了高溫熱暴露對快速凝固ＡｌＣＲＹＺｒ合金顯微組織影響和高溫國下力學性能的熱穩(wěn)定性。結(jié)果表明，快速凝固ＡｌＣｒＹＺｒ合金主要第二相為Ａｌ２０Ｃｒ２Ｙ（立方，ａ＝１．４３７ｎｍ）和ＣＯ２３Ａｌ３Ｚｒ（正方，ａ＝０．４０１３ｎｍ，ｃ－１．７３２ｎｍ），Ａｌ２０Ｃｒ２在５００℃熱暴露尚能保持其立方結(jié)構(gòu)，但質(zhì)點明顯粗化，甚至塊狀化，在

Abstract:The alloy LaNi 5 is a typical hydrogen storage material. Hydrogen storage batteries using LaNi 5 base alloy as cathodes have outstanding advantages. According to crystal structure of LaNi 5, the maximum hydrogen storage quantity of the LaNi 5 alloy is 1 33 H/M, that means 8 H atoms can be absorbed in a cell.

Abstract:Based on the anisotropic crystallographic theory, a model of low cycle fatigue (LCF) life time of a nickel base single crystal in a multiaxial stress state is proposed. The model indicates that LCF life time has a power relationship to total shear strain of modified octahedral slip. The detail distributions of stress and strain in a hellow cylinder specimen under tension torsion LCF loadings are analyzed in detail. The LCF life time model has been confirmed successfully using the results of tension torsion LCF tests of CMSX 2 NI base single crystal superalloy.

Abstract:研究了反應(yīng)燒結(jié)碳化硅陶瓷在１３００℃空氣中的高溫氧化行為。結(jié)果表明：高溫氧化過程中在試樣表面出現(xiàn)的非晶態(tài)ＳｉＯ２晶化以及氧化膜起裂，使得該陶瓷氧化曲線遵循對數(shù)氧化規(guī)律。

Abstract:對Ｎｉ－９．７Ｃｒ－５．５ｌ－７Ｔｉ濺射納米晶涂層進行了空氣中高溫氧化實驗，觀察并分析了Ｔｉ的作用及影響，研究結(jié)果表明：由于涂層中相對較高的Ｔｉ含量，１０００℃氧化２００ｈ后生成了由α－Ａｌ２Ｏ３和ＴｉＯ２組成的復雜氧化膜。ＴｉＯ的存在并沒有降低涂層的抗高溫氧化性能，而且生成的氧化膜與涂層基體有著很好的粘附性。這主要在于氧化初期生成的ＴｉＯ２在隨后氧化過程中沒有發(fā)生長大，從而保證了保持性氧化膜的完

Abstract:以單聚合物組元石蠟基粘結(jié)劑ＷＰ－ＥＶＡ和ＰＷ－ＨＤＰＥ作為對比，選擇具有良好產(chǎn)流變學性能的ＰＷ－ＥＶＡ－ＨＤＰＥ多聚合物組元石蠟基粘結(jié)劑，研究其脫脂保形性和分步快速脫脂過程。研究結(jié)果表明：采用分步快速脫脂，ＰＷ－ＥＶＡ－ＨＤＰＥ粘結(jié)劑中的ＰＷ、ＥＡＶ、ＨＤＰＥ可分別在３５０℃、４２０℃、５００℃有序地分為３步依交脫除，該粘結(jié)劑體系具有最佳脫脂保形性能。

Abstract:A novel W nano ThO 2 electrode has been prepared by hot pressing. Through vacuum arc discharge, electron emission sites on the cathode were examined using SEM. Also, the electric field strength of the starting arc was measured. As compared with the traditional electrode, the W nano ThO 2 electrode has a higher electron emission ability and a much lower work function.

Abstract:CuCr25W1Co1 electrical contact alloys were prepared by a vacuum smelting method and their properties were measured. The results show that selective strengthening by W and Co improves the breakdown fields of CuCr alloys, and that vacuum smelting is an effective method to produce CuCr contact material, it saves Cu and Cr, improves properties, and is suitable for large scale production.

Abstract:Using pure Ti and Ni powders, a porous TiNi shape memory alloy has been prepared by self propagating high temperature synthesis(SHS). The porous SHS samples possess a regular shape, stable dimensions, and relatively satisfactory porous interconnections etc. The density, maximum pore size, permeability, pore structure, element distribution and phase composition of the porous samples have been analyzed. The results show that the SHS process used for producing TiNi alloys with high porosity and low density possesses many advantages, such as full alloying, homogenous composition, high porosity (over 50%), simplifying processing, energy savings etc. Accordingly it is an ideal method for producing TiNi alloys.

Abstract:采用發(fā)射光譜分析技術(shù),研究了鈦及鈦合金中Zr,Ru,Pd,Hf,Cu,Y,V,Mo,Nb,Al,Co,Ni,Ta,Bi,Sn,Cr,Mn的光譜測定方法。結(jié)果表明,選用碳粉作為緩沖劑,使用淺孔電極和大電流激發(fā),一次攝譜可同時測定17個雜質(zhì)元素。測定下限為3×10-4%～15×10-3%,相對偏差在15%以內(nèi)。

Abstract:The working principle of polishing equipment for polishing the outer surface of zirconium alloy tubing for nuclear reacts is described. Some key issues in the development and operation features of the equipment are also presented. A free polishing method and four polishing heads with various sizes of abrasive tapes are adopted for long and minor zirconium alloy tubing, and multiple pass polishing can be conducted in one cycle of operation. An adjustable instrument with various functions can keep stabilize the operation of the equipment. The polishing process is controlled automatically.