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Abstract:研究了Al-1％Si合金水平連鑄過程中施加功率超聲對鑄坯凝固組織的影響，并對其機(jī)理進(jìn)行了探討。實(shí)驗(yàn)結(jié)果表明，隨著超聲波功率的提高，鑄坯凝固組織得到了細(xì)化，同時Si元素晶界偏析得到了抑制。理論分析認(rèn)為當(dāng)功率超聲頻率為22．3kHz時，能夠發(fā)生空化效應(yīng)的最大空化泡半徑為1．02×10^-4m，且隨著超聲功率的增加，空化泡數(shù)量增多?？栈荼罎r產(chǎn)生局部高溫高壓，從而導(dǎo)致晶粒細(xì)化，改善了Si元素的分布情況。

Abstract:討論了Mn對鎂基準(zhǔn)晶中間合金中三維二十面體球形準(zhǔn)晶相形成過程的影響。研究表明：當(dāng)在Mg-Zn-Y基準(zhǔn)晶中間合金熔體中加入一定量的Mn元素后，在常規(guī)鑄造條件下的結(jié)晶凝固過程中，完全可以改變Mg-Zn-Y基準(zhǔn)晶中間合金中準(zhǔn)晶的形成過程，獲得穩(wěn)定的均一二十面體初生Mg45Zn47Y5Mn3準(zhǔn)晶相，避免了十面體準(zhǔn)晶相的出現(xiàn)，改變了準(zhǔn)晶相最終的形貌，由于Mn的加入，使初生準(zhǔn)晶相的顆粒尺寸明顯變小，使之由尺寸為60gm～80gm的花瓣?duì)钭兂沙叽鐬椤?0gm的球形狀。Mn的加入，降低了鎂基準(zhǔn)晶中間合金的生產(chǎn)成本，為工業(yè)化生產(chǎn)提供了便利條件。

Abstract:用高溫固相法在900℃，保溫6h的條件下制備了YVO4單相粉末樣品。在紫外光254nm激發(fā)下，YVO4：Eu^3＋的激發(fā)光譜由VO4^3＋的吸收帶和Eu^3＋的電荷遷移帶組成。發(fā)射光譜為Eu^3＋的^5D0→^7Fj（J=1,2，4）躍遷。在Eu^3＋含量一定的情況下?lián)诫sBi^3＋和sc^3＋，隨著Bi^3＋濃度的增加，激發(fā)光譜寬化，但發(fā)射強(qiáng)度變?nèi)?；SC^3＋濃度的增加則使YVo4：Eu^3＋的發(fā)射強(qiáng)度先增加后降低。在147nm激發(fā)下，（Y,Bi，Sc）VO4：Eu^3＋的發(fā)射光譜相對于YVO4：Eu^3＋有降低趨勢。

Abstract:Electronic properties of several Hg1-xMnxTe wafers before and after chemical polish were characterized by Van Der Pauw method at 77 K. Results showed that values of resistivity and Hall coefficient of the wafers before etching are lower than those after etching, while Hall mobility and carrier density were higher. The maximum of resistivity decreased by 25%, the maximum of Hall mobility increased by 31%, but Hall coefficient and carrier density changed only by about 2% before and after etching. There existed a lot of dislocations in surface damaged layer, resulting in the decrease of Hall mobility of charge carrier, but the values of Hall mobility of wafers before chemical polish were higher, the minimum of which increased by 21%. It is a abnormal phenomena. All the experimental results can be explained using a three-layer model.

Abstract:以Pt，Pd，Rh3種貴金屬作為汽油車用三效催化劑的主要催化活性組分，制備了2組具有不同組合與分布形式的分層催化劑和分區(qū)催化劑，并通過發(fā)動機(jī)臺架測試系統(tǒng)進(jìn)行了催化活性評價。通過對表征催化劑催化性能的空燃比特性、起燃特性和催化轉(zhuǎn)化效率的對比分析，研究了3種貴金屬的組合與分布對催化劑3大特性的影響。結(jié)果表明：貴金屬的組合與分布方式會對催化劑的3大特性產(chǎn)生顯著影響；貴金屬分層分布催化劑與分區(qū)催化劑相比具有更高的空燃比特性和起燃特性，其中PtRh（o）／Pd（i）催化劑表現(xiàn)最佳，但貴金屬分區(qū)催化劑，主要是PtRh組合在近發(fā)動機(jī)端的分區(qū)催化劑，在所有催化劑中表現(xiàn)出最優(yōu)異的起燃特性；因此，在進(jìn)行歐3、歐4等車用排放控制系統(tǒng)設(shè)計(jì)時，可以利用不同貴金屬組合與分布催化劑的獨(dú)特性能優(yōu)勢，在同一載體或同一系統(tǒng)中的不同載體上進(jìn)行可控的貴金屬負(fù)載與分布，來提高催化劑的綜合性能；以這種方式獲得的效果預(yù)期比單純提高貴金屬含量獲得的效果好得多。

Abstract:The influence of Suction cast on phase structures and hydrogen storage properties of TiVCr based alloys has been investigated in this work. It is showed that suction cast is beneficial to the formation of a single solid solution phase with BCC structure resulting in the slight decrease of the lattice parameters. The slope coefficient Sf and the desorbing plateau pressure of the alloys were decreased and the capacity of absorption and desorption was increased by suction cast. Also, the activation performances of the alloys were reduced by suction cast. The desorbing plateau pressure and the capacity of desorption of the alloys increased with increasing Cr content.

Abstract:為開發(fā)免訓(xùn)練、高可恢復(fù)變形量的FeMnSiCrNi合金，研究了直接時效和形變時效對FeMnsiCrNiNbC合金形狀記憶效應(yīng)的影響，通過TEM分析了微觀組織的變化。結(jié)果表明：與直接時效相比，10％室溫形變后時效對合金形狀記憶效應(yīng)的提高更顯著。形變后產(chǎn)生的晶體缺陷提供了NbC的形核位置，使NbC的析出速度顯著增加，析出數(shù)量增多，粒徑減小，因而對基體的強(qiáng)化效果更顯著。同時NbC析出導(dǎo)致的彈性應(yīng)變場提高了應(yīng)力誘發(fā)￡馬氏體逆轉(zhuǎn)變的可逆性。

Abstract:On the basis of ascertaining that phosphomolybdic acid modified platinum electrode has higher catalytic activity to methanol oxidation, three kinds of transition metal substituted phosphomolybdic acids were synthesized, and the IR spectrum indicated that the compounds still kept Keggin structure. The transition metal substituted phosphomolybdic acid modified platinum electrodes were prepared, and the electrochemical behaviors of the transition metal substituted phosphomolybdic acid modified platinum electrodes and their electrocatalytic effects to methanol oxidation were studied. Meanwhile, the results showed that the three kinds of heteropolyacid modified platinum electrodes had higher electrocatalytic activity to methanol oxidation, manganese substituted phosphomolybdic acid modified platinum electrode had the highest electrocatalytic activity among them.

Abstract:采用熱液靜擠壓工藝對液相燒結(jié)態(tài)93W-4．9Ni-2．1Fe合金進(jìn)行了變形，擠壓溫度為1200℃，變形量60％～75％：系統(tǒng)研究了擠壓態(tài)合金力學(xué)性能與顯微組織之間的關(guān)系。結(jié)果表明，擠壓態(tài)合金的鎢顆粒內(nèi)部表征為高密度位錯構(gòu)成的胞狀亞結(jié)構(gòu)，而粘結(jié)相在擠壓過程中發(fā)生了動態(tài)再結(jié)晶。擠壓態(tài)合金的強(qiáng)度隨著變形量的增大而不斷增加，延伸率則隨著變形量的增大而不斷減小。

Abstract:HfO2 thin films were prepared by electron beam evaporation.The residual stress was measured by viewing the substrate deflection using ZYGO interferometer. The microstructure of the HfO2 thin films was inspected by X-ray diffraction (XRD). The results show that the stress is tensile and the value of the residual stress decreases with the increase of the thin film thickness, and residual stress becomes stable when the film thickness reaches a certain value. The interplanar distance of the thin film increases with the increase of the thin film thickness, which is corresponding to the variation of the residual stress. The evolution of the residual stress may be due to the variation of the microstructure as the increasing of the thin film thickness.

Abstract:GaN epitaxy films were grown on (0001) oriented sapphire substrate by metal-organic vapor deposition(MOCVD). AFM and SEM were used to analyze the surface morphology of GaN films. Hardness and critical load of GaN films were measured by an nano-indentation tester, friction coefficient by reciprocating UMT-2MT tribometer. It is found that the surface of GaN film is smooth and the epitaxial growth mechanism is in two-dimension mode, GaN epitaxy films also belong to ultra-hardness materials, whose hardness is 22.1 MPa and elastic modulus is 299.5 GPa. Adhesion strength of epitaxial GaN to sapphire is high, and critical load reaches 1.6 N. Friction coefficient against GCr15 ball is steadily close to 0.13, while GaN films turns to be broken rapidly by using Si3N4 ceramic ball as counterpart.

Abstract:The microstructure of the laser cladding coating with pre-placed B4C and B4C+Ti powders on TC4 substrate was analyzed using XRD, SEM and EDS. The results showed that both the coatings consisted of TiB2, TiB, TiC1-x and Ti phases. Some of Ti in the substrate was melted and mixed into the laser melting pool and reacted with B4C in-situ producing TiB, TiB2 and TiC1-x. The in-situ produced TiC1-x shows morphology of dendrite. The in-situ produced TiB2 shows morphology of whisker with larger size. The in-situ produced TiB shows morphology of whisker with smaller size. The bonding between the coating and TC4 alloy substrate was perfect. No crack and void were found at the interface. The heat-affected zone in the Ti substrate exhibited typical martensite morphology of quenched microstructure. Compared with B4C cladding coating, the B4C+10wt%Ti cladding coating had a finer microstructure and higher content of TiB phase and lower content of the TiB2 phase.

Abstract:采用熱分解法制備了以鈦為基體、SnO2＋Sb2O3為中間層、RuO2＋PbO2為活性層的Ti／SnO2＋Sb2O3／RuO2＋PbO2電極。應(yīng)用極化曲線法和循環(huán)伏安法測定不同RuO2含量下電極在25℃，0．5mol／LH2SO4溶液中的電催化活性。實(shí)驗(yàn)結(jié)果表明，隨著RuO2含量的增加，相同電極電位下的電流密度增大；相同的掃描速率下，RuO2含量增加，電極的伏安電荷值增加，即電極的電催化活性隨著RuO2含量的增加而增加。在1．0mol／LH2SO4溶液中，60℃、電流密度為2．0A／cm^2條件下，電極壽命快速檢測結(jié)果表明，Ti／SnO2＋Sb2O3／RuO2＋PbO2電極的壽命隨RuO2含量的增加而下降；但與不加有SnO2＋Sb2O3中間層的Ti／RuO2＋PbO2電極相比，電極壽命則顯著增加。RuO2的含量還對電極的表面形貌有明顯的影響。

Abstract:In order to develop the AB5-type hydrogen storage alloys with multi-component alloying elements, the alloys MlNi3.55Co0.3Mn0.4Al0.25Cu0.15Fe0.1Cr0.1Zn0.13Vx(x=0.02, 0.05, 0.08) were prepared, and their discharge capacity, cycle stability were tested and analyzed. The results show that the low-Co content hydrogen storage alloys with additive V has good electrochemical properties. It is found that the electrochemical properties of low-Co content hydrogen storage alloys with x=0.02 are better than those of the other alloys. The effect of V on the electrochemical properties is related to the change of the microstructures of the alloys.

Abstract:The influence of gold nanoparticles on the optical properties of dye molecules of Rhodamine 6G (R6G) and fluorescein (FL) has been studied. The adsorption of positively charged R6G on the surface of gold nanoparticles passivated with citrate resulted in a red-shift of the surface plasmon resonance (SPR) of the gold nanoparticles. Negatively charged FL, on the other hand, had slight influence on the SPR of the gold nanoparticles, likely due to the electrostatic repulsion between FL and citrates. The surface-enhanced Raman spectrum of R6G on the gold nanoparticles demonstrated that R6G adapted a parallel orientation relative to the surface of the gold nanoparticles. The nonradiative energy decay and unfavorable orientation of R6G to gold nanoparticles led to a decrease in the intensity of the emission of R6G. In contrary, the emission intensity of FL was substantially increased in the presence of the gold nanoparticles, due to the necessary space generated by the electrostatic repulsion between FL molecules and the citrate-passivated gold nanoparticles.

Abstract:The phase transition of Copper-tungsten films deposited on Si (100) and Al2O3 substrates took place by means of in situ annealing in vacuum chamber at different temperatures. X-ray diffraction (XRD) and the polarization phase shift technique were employed to characterize the microstructure and residual stress of Cu-W films, respectively. The results indicated that the two successive but distinctive stages of phase transition appeared with the change of annealing temperatures, i.e., W (Cu) solution formation and two-phase crystalline (W and Cu) structure formation. The relationship between phase transition and residual stress was investigated, the tensile stress was caused during phase transition, whereas it was released with crystalline growth.

Abstract:The roles of X-ray diffraction and electron diffraction have been reported in crystal structure study of LiCoO2, the cathode materials of lithium ion battery. The crystal structures of the LiCoO2 synthesised at different temperatures and the delithiated product LixCoO2(0

Abstract:采用新型等離子浸沒離子注入和沉積（PIIID）法以C2H2為等離子源對NiTi合金進(jìn)行表面改性。利用Raman光譜分析膜層結(jié)構(gòu)；采用納米壓痕和光電子能譜（XPS）分析涂層前后NiTi合金的表面力學(xué)性能和表面成分，利用電化學(xué)阻抗譜和動電極化測試涂層前后基體的耐腐蝕性能。結(jié)果表明：NiTi合金表面的膜層是DLC：經(jīng)過PIIID處理后，基體表面由原先的TiOz轉(zhuǎn)變?yōu)镈LC；納米硬度和楊式模量得到提高；耐腐蝕性能獲得明顯改善。

Abstract:用XRD和SEM對Mg-Ni體系燃燒合成產(chǎn)物進(jìn)行了研究。結(jié)果表明：Mg—Ni壓坯預(yù)熱至440℃以上均可熱爆合成Mg2Ni，且預(yù)熱速度越大產(chǎn)物越致密；過大的壓坯密度，降低了體系的燃燒溫度，影響Mg，Ni間的反應(yīng)程度；而對于細(xì)小的Mg粒，由于較高的燃燒溫度，導(dǎo)致合成產(chǎn)物出現(xiàn)嚴(yán)重的燒結(jié)現(xiàn)象；此外熱爆合成產(chǎn)物在一定溫度下適當(dāng)?shù)谋?，有助于提高M(jìn)g2Ni的純度。

Abstract:The kinetics of the hydrogen reduction of MoO3 to MoO2 and MoO2 to Mo were investigated. The results showed that the major step of the reduction of MoO3 to MoO2 was controlled by interface-chemical reaction. The apparent activation energy of this step was 58.1 Ll/mol. The major step of the reduction of MoO2 to Mo was controlled by inner diffusion. The apparent activation energy of this step was 30.1 kJ/mol.

Abstract:Nanostructured bulk of W-Cu alloy was prepared by mechanical alloying and hot pressed sintering. The nanostructured W-Cu material shows the characteristic of the spreading electric arcs, and the commercially used W-Cu alloy exhibits the characteristic of the localized arcs during the electric breakdown. The effect of nanostructured W-Cu alloy is caused by a larger number of electrons emitted during the discharge with a low electron work function, and highly conductive grain boundaries and many nano-metre-scale grains could narrow the potential barrier at the tungsten-copper interface.

Abstract:將Zr-Sn-Nb新鋯合金樣品分組進(jìn)行不同的熱加工，用透射電鏡（TEM）和高分辨電鏡（HRTEM）觀察并分析它們的顯微組織和第二相粒子成分。TEM觀察發(fā)現(xiàn)，1000℃樣品與580℃樣品相似，第二相粒子呈彌散分布。其它樣品中第二相粒子分布不太均勻，隨著保溫溫度升高，帶狀分布的第二相增多。EDS分析發(fā)現(xiàn)樣品中存在Nb／Fe比不同的2種Zr-Nb-Fe第二相粒子和不含F(xiàn)e元素的βNb粒子。

Abstract:對電阻率為10^3-6Ω·cm的In摻雜Cd0．9Zn0．1Te晶片在Te氣氛和Cd／Zn平衡蒸汽壓下進(jìn)行了熱處理，對電阻率為10^8-9Q·cm的非摻雜晶片則在In氣氛和Cd／Zn平衡蒸汽壓下進(jìn)行了熱處理。結(jié)果表明，In摻雜Cd0．9Zn0．1Te晶片經(jīng)處理后電阻率可提高3個數(shù)量級。非摻雜晶片在In氣氛中熱處理可很容易地改變導(dǎo)電類型，在熱處理溫度700℃，In分壓6．1×10^-4Pa，退火時間達(dá)48h后，電阻率可以提高到2．6×10^9Ω·cm。

Abstract:The mechanical properties of Ti-6Al-4V alloy by laser rapid forming (LRF) have been investigated. The results show that the mechanical properties of the as-deposited Ti-6Al-4V alloy have the characteristics of higher strength, lower ductility and more distinct anisotropy properties as compared to wrought. The microstructure, content of oxygen and metallurgical flaw of the laser formed samples will have effect on the tensile test results. It is the microstructures that play crucial roles on the mechanical properties, while the oxygen content and ill-bonding flaw are in the next place. For the LRF Ti-6Al-4V alloy with the oxygen content meeting GJB GJB2921-1997, a basket weave microstructure obtained through the solution-aging treatment brings forth the best mechanical properties. Not only the strength but also the ductility is over than that of the wrought specification.

Abstract:A new alloy belonging to Ti-AI-V-Si system has been developed on the base of Ti-6Al-4V, designated as TC4S. Experimental test results show that mechanical properties of TC4S have been improved evidently by proper adjusting the contents of Al and V, adding small amount of Si when compared with conventional Ti-6Al-4V alloy. The satisfied match among the strength, the ductility and the fracture toughness of the alloy has been reached, and meets the requirements of the design. The strength of TC4S alloy can be increased by 60 MPa-100 MPa on the condition of the slight damaging its plasticity and toughness, compared with Ti-6Al-4V ELI.

Abstract:采用放電等離子燒結(jié)（SPS），通過Ti與B4C之間的原位反應(yīng)合成TiC＋TiB／Ti復(fù)合材料。首先通過熱力學(xué)計(jì)算判斷可能發(fā)生的反應(yīng)，利用x射線衍射（XRD）、掃描電鏡（SEM）對球磨混合粉以及燒結(jié)后材料的相組成和顯微組織進(jìn)行了研究，測定材料的相對密度和硬度，并探討了Ti與B4C采用放電等離子燒結(jié)制備TiC＋TiB／Ti復(fù)合材料的致密化過程和反應(yīng)機(jī)理。結(jié)果表明，采用SPS技術(shù)，在1150℃保溫5min的條件下，Ti與B4C能同步完成反應(yīng)、燒結(jié)、致密化，生成TiC＋TiB／Ti復(fù)合材料，并且原位生成的增強(qiáng)相分布均勻且細(xì)小。

Abstract:通過鼠傷寒沙門氏菌回復(fù)突變試驗(yàn)（Ames試驗(yàn)）對TLE及TLM2種β型醫(yī)用鈦合金的致突變作用進(jìn)行生物學(xué)評價，試驗(yàn)分別設(shè)計(jì)5個劑量組、自然回變對照組、溶劑對照組以及陽性對照組，采用平板摻入法在加與不加S9混合液的條件下完成。統(tǒng)計(jì)學(xué)分析結(jié)果顯示：2種聲型醫(yī)用鈦合金每劑量組各菌株回變菌落數(shù)均與自然回變菌落數(shù)接近，未超過其2倍，而陽性對照組超過自然回變菌落數(shù)的2倍以上。說明TLE，TLM在檢測劑量（0．16ul/皿～100ul／皿）范圍內(nèi)反應(yīng)結(jié)果為陰性，即不具有點(diǎn)突變誘變性。

Abstract:采用拉伸試驗(yàn)、掃描電鏡和透射電鏡等測試手段，研究了固溶淬火后預(yù)變形程度對新型高強(qiáng)Al-Cu-Li-X鋁鋰合金2A97組織和性能的影響。結(jié)果表明：隨預(yù)變形量增加，135℃時效48h合金強(qiáng)度明顯提高，塑性緩慢下降，變形量為4．7％合金的抗拉強(qiáng)度為584MPa，延伸率為12．6％，淬火后的預(yù)變形量控制在4％-6％得到比較理想的強(qiáng)塑性匹配。預(yù)變形促進(jìn)基體乃相析出，并使其顯著細(xì)化和均勻分布。

Abstract:Amorphous melt-spun ribbons of Pr4.2Tb0.3Fe78B17.5 alloy were consolidated into bulk nanocomposite magnets by Spark Plasma Sintering method. Effect of sintering conditions on the density, microstructure and magnetic properties were studied. Higher sintering temperature improved the densification of the magnets, while deteriorated their magnetic properties simultaneously due to the excess crystal grain growth. Magnet possessed a Br of 1.04 T and a JHc of 220 kA/m under the optimal sintering condition, and its microstructure contained satisfied grains with an average size of about 20 nm.

Abstract:將AZ91D鎂合金鑄錠在330℃往復(fù)擠壓4道次后，在300℃連續(xù)正擠壓制成Ф5mm的絲材，用OM，SEM分析不同方式擠壓前后組織的變化，研究往復(fù)擠壓及隨后正擠壓對其組織與性能的影響。研究表明，AZ91D鎂合金往復(fù)擠壓4道次及連續(xù)正擠壓制備的矽5mm絲材組織均為等軸晶，晶粒尺寸分別為小于10um及1um～3um。經(jīng)往復(fù)擠壓及隨后的正擠壓，AZ91D鑄造鎂合金的綜合力學(xué)性能均可得到顯著提高，其主要原因是基體組織α-Mg和強(qiáng)化相β-Mg17Al12的細(xì)化。往復(fù)擠壓4道次后，材料真應(yīng)變高達(dá)20．36，正擠壓過程中等效應(yīng)變速率達(dá)到0．192s^-1，AZ91D鎂合金往復(fù)擠壓及正擠壓晶粒的細(xì)化機(jī)制主要包括破碎、動態(tài)再結(jié)晶和動態(tài)回復(fù)。

Abstract:通過高溫?zé)崮M壓縮試驗(yàn)和微觀組織研究，探索了熱變形參數(shù)對BT22鈦合金內(nèi)部顯微組織的影響。結(jié)果表明：BT22鈦合金組織對溫度敏感，鍛造建議在780℃進(jìn)行，嚴(yán)格控制溫升（尤其是終鍛溫度）。在兩相區(qū)鍛造時，隨變形速率的增加，α相尺寸減小。在60％～70％之間存在著晶粒明顯細(xì)化的臨界變形量，這一臨界變形量是鍛造時必須控制的最小變形量。

Abstract:以MgO為原料、RECl3-KCl-MgCl2為電解質(zhì)，熔鹽電解法制取Al-Mg-RE三元合金。結(jié)果表明：RE是由Al直接還原得到，而Mg是由電解得到的：可制得RE含量為0-8％～1．2％，Mg含量為1％-4％的三元合金；電解溫度在720℃～780℃之間，電流效率隨電解溫度的升高而升高，電流效率最高可達(dá)到81．3％，但超過780℃，電流效率隨電解溫度的升高而降低；電流密度在0．8A／cm^2時電流效率最高，過低或者過高的電流密度都可以降低電流效率；電解過程中基本上不產(chǎn)生Cl2。

Abstract:Through thermodynamic calculation and experiment analysis, the cause of impurity forming in preparing La1-xSrxMnO3 by self-propagating high-temperature synthesis (SHS) was studied and the suggestion was given in this paper to avoid or diminish it. The results show that La2SrO4 impurity was produced inevitably in the products synthesized by SHS because the Gibbs free energy of La2SrO4 forming reaction is equivalent to that of SrMnO3 forming reaction when MnO2 was adopted as dilution. When La1-xSrxMnO3 was used as dilution, La2SrO4 forming could be avoided. The over-dilution of La1-xSrxMnO3 resulted in Mn3O4 impurity forming, which could be avoided by adjusting the proportion of dilution and controlling the reaction speed and system temperature of SHS process.

Abstract:采用粉末冶金法制備高溫稀土永磁Sm（Co0.72Fe0．15Cu0.1Zr0．03）7.5，研究了燒結(jié)溫度對磁體磁性能的影響。結(jié)果表明：燒結(jié)溫度過低，則磁體的致密度較低，難以獲得優(yōu)良的磁性能；燒結(jié)溫度過高，則Sm揮發(fā)，磁體的Sm含量降低，磁性能惡化。磁體的最佳燒結(jié)條件為：溫度1215℃，保溫45min。在上述條件制備的磁體在25℃及500℃時的剩磁夙、內(nèi)稟矯頑力Hci、最大磁能積（BH）max分別為：0．94T，2276．6kA／m，171．9kJ／m^3及0．67T，509．4kA／m，81.2kJ／m^3；磁體的占．日退磁曲線在500℃時保持為直線，內(nèi)稟矯頑力溫度系數(shù)聲（25℃-500℃）為-0，16％／℃，最高使用溫度達(dá)到533℃。

Abstract:To avoid the disadvantages resulting from the interface between matrix and reinforcement for metal matrix composites (MMCs), a novel in-situ synthesizing technology, based on powder metallurgy, is presented in this paper. A kind of aluminum matrix composite reinforced by in-situ intermetallic compound fiber was prepared. The results showed that in-situ fiber was distributed uniformly in matrix, parallel to the extrusion direction. Yield strength of in-situ MMCs is 28% and 95.7% higher, respectively than those of ex-situ MMCs and matrix aluminum, and fracture strength is increased by 20.6% and 88.5% correspondingly. The strengthening mechanism of in-situ MMCs is that the excellent interface bonding between the matrix and the reinforcement. The matrix exhibits its strong strength, and the reinforcement exhibits its strong strength. The fracture mechanism of in-situ MMCs is the brittle fracture and cleavage crack of fibers.

Abstract:采用差熱分析、顯微硬度測試、X射線衍射分析對牙科低金含量銀鈀合金的時效強(qiáng)化機(jī)制進(jìn)行了初步探討。結(jié)果表明：400℃等溫時效20min和459℃等溫時效10min樣本的顯微硬度較ST組樣本分別提高了50％和128．5％，600℃等溫時效5min組樣本顯微硬度較ST組樣本降低了8％；合金在459℃和600℃有明顯CuPd相析出，但是CuPd相與硬度的提高沒有聯(lián)系，合金硬度提高與Cu原子從基質(zhì)相析出有關(guān)。

Abstract:利用能譜分析（EDS）、掃描電鏡（SEM）和電化學(xué)測試等分析手段，研究了以微弧氧化為前處理，以硫酸鎳為主鹽的鎂合金“無氟酸性”化學(xué)鍍工藝及其鍍層性能。結(jié)果表明：微弧氧化膜可以有效地防護(hù)鎂合金，在其表面實(shí)現(xiàn)以硫酸鎳為主鹽的“無氟酸性”化學(xué)鍍，得到了對環(huán)境友好的化學(xué)鍍新工藝：所得微弧氧化一化學(xué)鍍層致密、顆粒細(xì)小，鍍層HV硬度為10195MPa，耐蝕性能顯著提高，自腐蝕電位提高為-0．2V左右，鈍化區(qū)間達(dá)800mV左右：化學(xué)鍍層與鎂合金基體結(jié)合力明顯加強(qiáng)。

Abstract:The mechanical properties of SiC Particulate reinforced AZ81 magnesium Base composites prepared by powder metallurgy were studied in the article. The mechanism of mechanical properties was also investigated. The experimental results show that tensile strength, fracture toughness, Vickers hardness of SiCp/AZ81 composites were remarkably improved when a proper volume of SiC were added, their maximum can reach 271.61 MPa, 5.96 MPa-m1/2, 2.52 GPa, respectively.

Abstract:采用粉末注射成形方法制備了鈦合金坯體，然后利用溶劑脫脂方法脫除坯體中可溶性粘結(jié)劑。通過對溶劑脫脂動力學(xué)分析表明，在脫脂過程中，存在動力學(xué)控制步驟轉(zhuǎn)化的過程，提出了脫脂臨界厚度的概念。當(dāng)厚度超過5mm時，試樣脫脂過程受擴(kuò)散控制，在常溫下進(jìn)行溶劑脫脂時，其擴(kuò)散系數(shù)為1．86×10^-6cm^2·s^-1，活化能為12．96kJ．mol^-1.K^-1；在厚度小于5mm時，試樣脫脂過程受粘結(jié)劑溶解和擴(kuò)散混合控制。

Abstract:采用擠壓鑄造法制備TiB2p／Al復(fù)合材料，并借助XRD，SEM，TEM和三點(diǎn)彎曲、摩擦磨損等分析測試手段研究了該材料的組織和性能。結(jié)果表明，復(fù)合材料組織致密，顆粒分布均勻，相組成主要為Al和TiB2。TEM觀察表明，T6態(tài)復(fù)合材料基體中發(fā)現(xiàn)大量細(xì)小的β＇析出相和位錯。部分界面上存在不連續(xù)的塊狀反應(yīng)物MgAl2O4。45％TiB2P／Al（體積分?jǐn)?shù)，下同）復(fù)合材料的抗彎強(qiáng)度為934MPa，彈性模量為183GPa，比30％TiB2P／Al復(fù)合材料的分別提高了34％和28％。常溫干摩擦條件下，TiB2P／Al復(fù)合材料摩擦系數(shù)變化平緩（在0．2左右波動），明顯低于鋁合金的摩擦系數(shù)；且復(fù)合材料的磨損表面較為平整、光滑，未觀察到大塑性變形，呈現(xiàn)出良好的自潤滑性能。

Abstract:TiB2/Cu matrix Interpenetrating phase composites (IPCs) with high ceramic content (~vol.83%) were prepared adopting high temperature sintering and subsequently melt-infiltration. The morphologies and microstructures of TiB2/Cu IPCs before and after thermal ablation were studied by SEM and EPMA. The thermal shock behavior and ablation-resistance of TiB2/Cu IPCs were investigated using plasma arc heating. The results showed that no crack was found on the ablated surface during the process of instantaneous heating and cooling, which revealed that TiB2/Cu IPCs have a good thermal shock resistance. Melt Cu phase presented obviously a gradual distribution among the ablation zone, transition zone and matrix zone, and no metal phase was detected near the ablation zone, it means that the melt play a role of sweat cooling during elevated temperature. The ablation-resistance mechanisms mainly include sweat cooling, chemical ablation and mechanical denudation.

Abstract:Copper was induced into W powder by electroless, The compacts made from chemical copperplated W powder were infiltrated, and W/15 Cu composites were prepared. The microstructures of the composites were investigated by mean of scanning electron microscope Density, hermeticity and coefficient of thermal expansion were measured. After comparing microstructures and physical property of the W/15Cu made by conventional process, the effects of chemical copperplated W powder on properties of W/15Cu were discussed. The results showed that chemical copperplated W powder could improve the compactibility of W compact, the microstructure and the physical properties of W/15Cu composite. It is indicated that when the compact contains 2% copper, the properties of the material are fairly satisfactory.

Abstract:Adopting a novel synthesizing method-low temperature reaction melting (LRM), a MgO particulate reinforced magnesium matrix composite was in-situ fabricated using pre-oxidized Mg powders. The microstructures and mechanical properties of the composite were investigated by microstructure observation and tensile tests. The results showed that, due to the melting of Mg powders during LRM treatment, the oxide film on the surface of Mg powder was effectively broken into pieces, refined and subsequently, spheroidized into particulates with micron or sub-micron sizes by the joint effect of the liquid phase Mg and the surface tension of MgO itself. Moreover, The formed MgO particulates possess not only good interfacial bonding with the matrix and uniform distribution, but also high strength and stiffness, which is beneficial to improving the reinforcement effect to the matrix. As a result, the LRM method can bring better microstructures and mechanical properties to the composite compared to powder metallurgy process.

Abstract:Composite electroplating is one of the new methods to produce composite materials, it has been developed rapidly in the last three decades, especially in technology and properties, but the research of its forming mechanism lags behind the research of technology and properties. In this paper, based on the review of enough research works, the general situation research was introduced from the point of view of history and status quo, the main contents and application scope were reviewed, and the mathematical models were presented, as well as the latest progress on composite electroplating mechanism was discussed. Meanwhile, its research direction and developing trends were prospected.