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Abstract:采用SCS－6 SiC連續(xù)纖維和箔－纖維－箔法制備SiC長纖維增強的TC4和Ti40基復(fù)合材料，研究復(fù)合材料的微觀組織結(jié)構(gòu)，結(jié)果表明：采用925℃的固化工藝制備長纖維SiC/TC4 和SiC/Ti40復(fù)合材料是合適的；SiC/TC4和SiC/Ti40復(fù)合材料的界面反應(yīng)層厚度分別為0．8μm和0．6μm，基體與纖維的界面結(jié)合良好，在SiC/Ti40復(fù)合材料兩纖維間區(qū)域存在TiC析出物。

Abstract:Considering the characteristics of centrifugal casting technology with investment shell, the mathematical model of solidification process of gamma titanium aluminide turbochargers was established, and the model for shrinking and feeding was deduced under the condition of centrifugal pressure. Then, temperature field and shrinkage defects of gamma titanium alunimide turbocharger with different technologies were simulated. The results showed that the temperature distribution could be calculated and the shrinkage defects could be predicted with the model, and the simulation results coincided with the experimental results quite well. It is indicated that the optimum process to remove shrinkage defects presented in the preceding paper is rational.

Abstract:采用X射線衍射儀（XRD）和差熱分析儀（DTA）研究了Mo-67at%Si元素混合粉末在中等強度的機械研磨（合金化）過程中的結(jié)構(gòu)變化過程，結(jié)果表明，在中等強度的研磨過程中，β－MoSi2是初生相，且在隨后的研磨過程中非晶化；在高研磨強度下生成α－MoSi2的量大于β－MoSi2,且α－MoSi2的含量隨研磨時間的增加而增加，差熱分析表明亞穩(wěn)相β－MoSi2隨溫度的升高會向α－MoSi2轉(zhuǎn)變。

Abstract:通過大角度的粉末X射線衍射測定了正磷酸鈉鉀鈣[(Ca2KNa(PO4)2)]晶體陶瓷的晶格參數(shù)，分析化學(xué)純度的碳酸鈣，磷酸二氫鉀、磷酸二氫鈉按照2：1：1的摩爾比混合后于1300攝氏度高溫反應(yīng)4h，得到了組合符合Ca2KNa(PO4)2的正磷酸鈉鉀鈣陶瓷，在10度－130度的2θ掃描角范圍內(nèi)，在室溫下進(jìn)行粉末X射線衍射。測定結(jié)果顯示，高溫合成的Ca2KN2(PO4)2晶體相是α－CaKPO4和α－CaNaPO4晶體的高溫固溶體，呈六方晶體結(jié)構(gòu)，晶格參數(shù)為：α0＝0．54396nm,C0=0.72976nm，晶胞體積V＝0．187nm^3.

Abstract:A model for the temperature field across the interface during explosive welding has been proposed. The model can be used to analyze the reason of amorphous phase emerging on the interface during explosive welding, and the results can explain the phenomena as metioned above very well.

Abstract:用原位自生法制備了Ti－54Al-x B(at%)和Ti-50Al-x B(at%)合金并利用XRD和SEM對合金的相組成和微觀組織進(jìn)行了研究，結(jié)果表明：細(xì)棒狀TiB2主要以數(shù)個或更多個呈族聚形式分布于晶界處，細(xì)棒狀TiB2(1010}面存在與[0001]晶向垂直的薄片狀凸耳；有些細(xì)棒狀TiB2生長成垂直交叉狀的簡單十字形或“T”字形，族聚形式細(xì)棒狀TiB2實際為三維空間較復(fù)雜的十字或“T”字形的復(fù)合形，研究還表明，細(xì)棒狀十字形TiB2晶體的這種結(jié)果與其{1010}面上的生長臺階有關(guān)。

Abstract:The forming mechanism for the crack produced in the process of laser forming 316L stainless steel powder alloy has been studied in the paper by micro measurements. The results show that the cladding cracks were formed in grain boundary with dendritic structure commonly and presented a characteristic of cracking along grains. There was obvious oxidation color on the fracture section of the cracks. SEM photos show that the orientation and profile of dendrite grains are distinct and the dendrites are rather round on the crack surface. All these show that the cracks were formed at high temperature. The crack formed in the cladding layers is the solidification crack, which belongs to the domain of hot crack, mainly due to the separation of the liquid films in the grain boundary under the action of tension stress existed in the cladding layers which was produced in RLF process.

Abstract:利用熱力學(xué)計算,分析了一些材料在高溫下與金屬鈾及鈾合金反應(yīng)的可能性,得到了這些反應(yīng)ΔG°與溫度的關(guān)系圖。通過比較和分析這些材料對鈾及鈾合金熔體在高溫下的化學(xué)穩(wěn)定性,發(fā)現(xiàn)氧化釔對金屬鈾和鈾合金熔體的化學(xué)穩(wěn)定性最好,為熔鑄金屬鈾和鈾合金的石墨坩堝理想涂層材料。

Abstract:采用高頻感應(yīng)對ZM5鎂合金表面進(jìn)行合金化改性處理，并對改性層組織和腐蝕行為進(jìn)行了研究，結(jié)果表明，鎂合金經(jīng)高頻感應(yīng)表面合金化改性處理，表層區(qū)域具有幾乎連續(xù)的β－（Mg17Al12)相的細(xì)化晶粒區(qū)，認(rèn)為這種均勻連續(xù)的β相將外部環(huán)境與鎂的合金中的α相隔離，從而使鎂合金的腐蝕速率降低。

Abstract:采用粉末冶金法制備出PSZ－Ni系復(fù)合材料，對不同組成的復(fù)合材料在20℃－1200℃升溫氧化過程進(jìn)行了TC分析。結(jié)果表明，金屬Ni組元的氧化程度隨陶瓷組元的增加而增加，且高溫時更加嚴(yán)重，其原因主要是：一方面PSZ具有較高的導(dǎo)氧率導(dǎo)致氧向材料內(nèi)部迅速擴散；另一方面，大量的金屬－陶瓷界面大大縮短了氧的擴散途徑；PSZ高的導(dǎo)氧率以及金屬（陶瓷）是呈顆粒分散存在，使金屬的表面積大大增加導(dǎo)致金屬相氧化加劇。

Abstract:A corrosion resistant Ni2Si/Ni3Si2 silicide alloy coating was fabricated on a substrate of low carbon steel A3 by laser cladding of the Ni76Si24 alloy powders. The laser clad silicide alloy coating has a rapidly solidified homogeneous microstructure consisting of plate like Ni2Si primary phase and minor amount of Ni2Si/Ni3Si2 eutectics and is metallurgically bonded to the steel substrate. The corrosion resistances of the silicide alloy coating in the water solutions of 0.5mol/l H2SO4 and 3.5% NaCl were evaluated utilizing the electrochemical polarization corrosion test method. Because of the inherent excellent corrosion resisting properties of the constituting phases Ni2Si and Ni3Si2, and the rapidly solidified homogeneous microstructure, the laser clad Ni2Si/Ni3Si2 silicide alloy coating exhibits excellent corrosion resistance.

Abstract:The powder sintered technology for manufacturing thick metal hydride electrodes has been extensively investigated. A slurry consisting of hydrogen storage alloy powder mixed with fine nickel powder and some additives was pasted onto the nickel foam as a current collector. By choosing adjustable sintering parameters, the composite metal hydride electrode was obtained. The effects of sintering parameters on the electrochemical properties of sintered metal hydride electrode have been characterized. The results showed that the activation and high rate discharge ability were greatly improved and comparable to that obtained with conventional pasting process for sintered hydride electrode. In order to design the thick metal hydride electrode Suitable for the oxygen diffusion electrode of airmetal hydride semi fuel cell, the electrochemical characteristics of thick metal hydride electrode were comparativly studied for different metal substrates, suchas perforated nickel strip, perforated copper foil and copper mesh. As a consequence, the thick metal hydride electrode employing the perforated copper foil as a current collector has been evaluated to be suitable for the airmetal Hydride semi fuel cell.

Abstract:A kind of new type lubricating coat for cold drawing of titanium alloy was developed with chemical method. The coat with grey black color possesses strong bonding force with titanium alloy matrix, and is mainly composed of Na3TiOF5.The tensile frication resistance forces are greatly reduced and the surface reality of titanium is improved when this kind of coat was applied with the mixed solid lubricants of graphite and MoS2 .

Abstract:The effects of the microstructure and the strain rate on the room temperature tensile properties of Ti 47Al 2Cr(at%) with fully lamellar microstructures were investigated. It is shown that the room temperature tensile strength and ductility increase with the decrease of colony size and lamellar spacing. The room temperature tensile strength increases with the increase of strain rate. The room temperature ductility of low ductility alloy is not sensitive to strain rate, but the ductility of high ductility alloy is sensitive and increases with the increase of the strain rate.

Abstract:This paper focuses on the main factors on heat conductivity for carbon carbon composites: the orientation of the carbon fiber; the temperature of heat treatment and the microstructure of the pyrolytic carbon matrix. The results show that it is the CVD pyrolytic carbon that determines the heat conductivity of carbon carbon composites, and the effect of heat treatment temperature is limited. The results also show that the CVD pyrolytic carbon that has high concentration of RL has high heat conductivity.

Abstract:對定向凝固Ni3Al基超合金IC6，以不同功率密度的強脈沖離子束進(jìn)行照射，利用X射線衍射分析，研究了輻照后材料表面所產(chǎn)生的物相變化，結(jié)果表明：當(dāng)以低功率密度輻照時，材料表面形成形變織構(gòu)；隨著功率密度的增加，材料表面還會發(fā)生部分非晶化，當(dāng)功率密度進(jìn)一步增加時，材料表面出現(xiàn)了新相。

Abstract:The hydrogen storage properties of Ti1.2Fe+xwt%Mg(x=1,3,5) alloys have been investigated. The results show that the modified alloys can be activated at room temperature without any thermal treatment because of the addition of Mg and excess stoichiomentriy of Ti in alloys. The alloy Ti1.2Fe+3wt%Mg(Ti1.2FeMg0.12)is comparatively light in weight and has a large storage capacity,attaining 1.9wt%H2(213 ml/g),and small pressure hysteresis, so suitable for the hydrogen storage system with portable hydrogen fuel cell power. In the paper, the influence and mechanism of the addition of Mg and excessive Ti on the activation behavior and hydrogen storage capacity for the alloys have also been discussed.

Abstract:采用熱壓反應(yīng)燒結(jié)技術(shù)，使用Ti-Ni混合金屬粉末焊料對SiC陶瓷進(jìn)行連接，探討了焊接溫度、保溫時間、焊料厚度以及焊接壓力等工藝參數(shù)對連接件抗彎強度的影響規(guī)律，并通過對連接界面及焊料反應(yīng)產(chǎn)物進(jìn)行SEM，EDS，XRD分析，進(jìn)一步考察了焊接工藝對連接件的斷裂類型，焊料反應(yīng)產(chǎn)物及其結(jié)合強度的影響規(guī)律。結(jié)果表明，采用適當(dāng)?shù)倪B接工藝，Ti-Ni焊料與母材可通過適當(dāng)且適度的界面反應(yīng)獲得牢固結(jié)合，此時界面反應(yīng)產(chǎn)物為以TiC,NiTi為主含Ni3C,Ni16Ti6Si7的混合物，且具有較高強度的TiC以彌散相形式分布在以具有一定韌性的金屬間化合物NiTi為主的基質(zhì)中，對接頭性能的改善起到關(guān)鍵作用。在本實驗范圍內(nèi)，在連接溫度1100攝氏度，保溫時間20min，焊接壓力12．7MPa，焊料厚度0．3mm條件下可獲得最佳陶瓷接頭，其相對抗彎強度為53％。

Abstract:分析了β'Sialon和Ce-TZP陶瓷熱擠壓模的力學(xué)性能，并與3Cr2W8V模具鋼熱擠壓模進(jìn)行對比試驗。結(jié)果表明：2種陶瓷熱擠壓模的使用壽命均明顯高于3Cr2W8V熱作模具鋼熱擠壓量；β'Sialon陶瓷熱擠壓模的使用溫度明顯高于Ce-TZP陶瓷熱擠壓模的使用溫度。

Abstract:在845℃－860℃，6min的真空條件下，采用AgCuTi焊料封接藍(lán)寶石與熱等靜壓99％氧化鋁，研究了AgCuTi焊料與藍(lán)寶石界面的反應(yīng)機理，同時對影響封接結(jié)合強度與氣密性的因素－氧化鋁的表面狀況和焊接后的退火進(jìn)行了分析，得出了控制焊接質(zhì)量的處理方法。