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Abstract:介紹了Mo，Ta，W藥型罩材料的制備、材料的力學性能及材料的彈道試驗。結果表明，Mo，Ta，W，貧鈾合金的侵徹性能均較傳統(tǒng)Cu藥型罩材料有很大的提高，完全可替代Cu材并滿足現(xiàn)代武器發(fā)展的要求。同時，還提出了難熔金屬藥型罩材料的研發(fā)方向。

Abstract:采用粉末冶金方法制備多孔鈦樣品，孔隙率約為40％，最大孔徑為240μm。經(jīng)過NaOH溶液、熱處理后，多孔鈦再在Na2HPO4溶液和飽和Ca(OH)2溶液中分別浸泡進行預鈣化處理。未經(jīng)預鈣化處理的樣品在SBF中浸泡，形成表面磷灰石涂層約需28d的時間。經(jīng)過預鈣化的樣品在SBF中浸泡只需4d，這說明預鈣化過程大大提高了多孔鈦的生物活性。其作用機理為：預鈣化過程中樣品表面的鈦酸鈉水解，形成帶負電的Ti-OH基團，使Ca^2 離子吸附到表面。在SBF中浸泡時，表面附近在短時間內達到鈣一磷過飽和。且Ca^2 離子增大表面附近的DH值，Ca^2 離子和PO4^3-離子、OH^-離子的活度積增大，刺激了磷灰石成核并形成涂層。除堿熱處理并預鈣化的樣品外，其余樣品表面磷灰石的Ca／P原子比均小于人體自然骨的Ca／P原子比。涂層的結晶細小而薄，不破壞多孔鈦的孔隙結構。

Abstract:Osteoblast differentiation of rabbit bone marrow cells on apatite-coated titanium by alkali-heat treatment was investigated in present paper. Titanium was subjected to alkali-heat treatment and soaked in acellular simulated body fluid to prepare surface apatite layer. Cell behavior and alkaline phosphatase activity and osteocalcin on apatite-coated titanium were compared with those on commercially pure titanium in vitro. The results show that initial cell adhesion on apatite-coated titanium is higher than that on pure titanium while cell growth rates at a late stage are not significantly different for both groups. Early and later osteoblast differentiation marks, alkaline phosphatase activity and osteocalcin, on apatite-coated titanium are higher than those on pure titanium. Apatite-coated titanium by alkali-heat treatment can increase osteoblast adhesion and displays a higher differentiation capacity for osteoblasts differentiation than that for commercially pure titanium.

Abstract:Polycrystalline samples La2/3Ca1/3MnO3 (LCMO), La2/3(Ca0.5Ba0.5)1/3MnO3 (LCBMO), La2/3Ba1/3MnO3 (LBMO), La2/3(Sr0.5Ba0.5)1/3MnO3 (LSBMO) and La2/3Sr1/3MnO3 (LSMO) have been prepared by a solid state reaction method. We have observed the temperature dependences of the electric resistivity and magnetoresistance from 77 K up to 800 K. Experimental results indicate that the presence of grain boundaries in the colossal magnetoresistance (CMR) materials prepared by the mechanical alloyed method leads to a large magnetoresistance effect at low temperature, and there exists a pronounced metal-semiconductor transition around TC. According to the models of spin-polarized electron tunneling and percolation, the magnetoresistance as a function of temperature has been explained well. The temperature dependence of resistivity at high temperature is well fit by nonadiabatic small polaron hopping model for LCBMO and LSBMO samples, and their activation energies are obtained. Also it has been found that annealing processing affects the resistivity significantly.

Abstract:為深入研究激光熔覆反應合成TiCp／Al復合材料過程，數(shù)值計算該過程的溫度場和流場時需將所發(fā)生的化學反應熱納入計算。因此本文采用在試樣掃描過程中突然停止激光發(fā)射的辦法，得到反應過程中不同階段所形成的組織，進而判斷出各階段所發(fā)生的反應；利用差熱分析法(DTA)和熱力學計算法確定反應熱焓值。研究表明：激光熔覆條件下Al-Ti-C粉料層中合成反應的過程為：先發(fā)生3Al Ti→Al3Ti反應，再發(fā)生Al3Ti C→TiC Al反應。3Al Ti→Al3Ti的反應熱為146．63kJ／mol，Al3Ti C→TiC Al的反應熱為38．60kJ／mol。該反應熱焓值可用于溫度場和流場的數(shù)值模擬計算。

Abstract:The SmCo/Cr films have been prepared with the help of DC magnetron sputtering method. The structure of Cr underlayer depended on several sputtering factors, and directly influenced the coercivity of SmCo/Cr films. The orthogonal design of experiments and mathematical statistical method are considered as the effective methods to optimize sputtering condition of Cr underlayer for high coercivity of SmCo/Cr films. Using the orthogonal design method, the effects of the four factors, such as, the target-substrate distance, the DC power, the sputtering pressure and the sputtering time were simultaneously investigated by only 9 experiments. The optimal condition of Cr underlayer was obtained, that is 4 cm in T-S distace, 50 W in DC power, 0.5 Pa in sputtering pressure, 9 min in sputtering time. The target-substrate distance, the DC power and the sputtering pressure are very important factors for coercivity, on the other hand, the effect of sputtering time is not obvious. It can be proved that our orthogonal design of experiment is of 95% confidence.

Abstract:The isothermal CVI (chemical vapor infiltration) process of carbon/carbon composites is controlled by many factors and its efficiency is very low. Manufacturing of C/C composites with isothermal CVI processes is costly and thus limits commercial applications of C/C composites. Based on the fuzzy neural network (FNN) technique and genetic algorithm, a predicting system for isothermal CVI process was proposed and established. The simulation results of FEM called virtual samples were selected as the network's training samples. Based on the FNN system, the influences of main infiltration parameters, such as infiltration temperature, precursor gas flow ratio and rate, had been studied; and they are good instructions for the design and optimization of CVI process. Using this FNN system, we expect that we can reduce the time of development and densification, thus reducing manufacturing cost.

Abstract:An artificial neural network (ANN) model is proposed to predict mechanical properties of Ti-10V-2Fe-3Al titanium alloys. The input parameters of the neural network (NN) model are deformation temperature, degree of reduction, cooling rate, solution temperature and aging temperature. The outputs of the NN model are five most important mechanical properties namely ultimate tensile strength, tensile yield strength, elongation, reduction of area, and fracture toughness. Extensive experiments for correlating forging technology to mechanical properties were conducted in Ti-10V-2Fe-3Al alloy to train the NN. Compared to the traditional regression method, the ANN model has a better compatibility and adaptability. The model can be used for the prediction of properties of Ti-10V-2Fe-3Al alloy as functions of processing parameters and heat treatment cycle. It can also be used for the optimization of the processing and heat treatment parameters.

Abstract:W6.56Ni2.28Fe tungsten heavy alloy from the elemental powders of W, Ni and Fe was mechanically alloyed(MA). Phase was defined by XRD. Microstructure was observed by TEM (JEM-2000 type). Phase evaluation, grain size and lattice distortion of these powders were determined and discussed. And nano-crystalline supersaturated solid solutions and amorphous were prepared by MA. A thermodynamic model was developed based on Miedema semi-experimental theory to calculate the driving force for phase evolution. The thermodynamic analysis showed that there is no chemical driving force to form amorphous alloys. The model of multilayer amorphization during MA was applied to illustrate the feasibility of amorphization of powder with neither ?Hmix << 0 nor DB >DA

Abstract:含鍶羥基磷灰石的骨缺損修復效果優(yōu)于羥基磷灰石。采用濕法合成含鍶羥基磷灰石和羥基磷灰石，分別在300℃，600℃，900℃熱處理。用Rigaku D／max-3C型X射線衍射儀(XRD)，PE1760．X傅氏紅外光譜儀(IR）和X射線散射能譜(EDX)分析粉樣和片樣的成分，用S-2700掃描電鏡(SEM)觀察形貌。結果表明：鍶使羥基磷灰石的晶面間距變大，熱穩(wěn)定性變差，900℃熱處理分解出β-Ca3(PO4)2和CaO2含鍶羥基磷灰石的OH^-紅外吸收峰弱于羥基磷灰石，但兩者的Off和PO4^3-峰位置接近；含鍶羥基磷灰石在模擬體液中的溶解．再結晶過程強于羥基磷灰石。

Abstract:Transformation characters of two kinds of TiNiCu two-way shape memory effect (TWSME) spring during excension and contraction training were investigated by DSC measurement during thermo-mechanical training. One of the TWSME spring could extend upon heating and contract upon cooling, the other could contract upon heating and extend upon cooling. The results showed that before training the profile of endothermic peaks were composed of several small peaks. With training the amount of the small peaks decreased. After the stabilized TWSME induced into the TiNiCu alloy, there was only one sharp peak appear. This can attribute to the dislocations structures creates an anisotropic stress field, which guides the orientation of martensite variants very similar. And the dislocations also leads to the decrease of As and Af.

Abstract:提出了粉末注射成形冷凝蒸氣脫脂新方法，介紹了其工作原理，考查了脫脂溫度、時間對粘結劑脫除率的影響。根據(jù)Fick第二定律建立了粉末注射成形平板試樣、球形試樣和圓棒試樣冷凝蒸氣脫脂過程的數(shù)學模型，并給出了該模型的1種圖形解法。實驗結果表明：該方法脫脂效率高，脫脂坯強度大。利用所建立的機理模型和圖形解法可以對簡單規(guī)則形狀成形坯的脫脂過程進行預測，預測結果與實驗結果很好的吻合。

Abstract:熱處理溫度顯著影響Ni3Al(Zr)合金的顯微組織和室溫力學性能。本實驗采用SEM，TEM，AES等手段對軋制處理后的試樣進行了研究。隨著熱處理溫度升高，再結晶體積百分數(shù)增加，再結晶晶粒尺寸增大，室溫拉伸強度降低。但室溫拉伸塑性隨熱處理溫度升高而增加，在850℃熱處理時達到最大值，然后隨熱處理溫度升高而顯著降低。俄歇能譜(AES)研究表明Zr在850℃熱處理時的晶界偏聚量明顯高于1100℃熱處理時的偏聚量，說明Zr在室溫的塑化作用與其在晶界的分布有關。

Abstract:Basswood was transformed by high-temperature pyrolysis into carbon performs (charcoal) and subsequently converted into cellular SiC-ceramics possessing pseudomorphous microstructure by the reactive-infiltration of Si into CB-template in Ar atmos- phere.Thermogravimetric analysis (TGA) was applied to reveal the pyrolysis behavior of basswood powder.Scanning electron microscopy (SEM) and X-ray diffraction (XRD) were employed to characterize and analyze the microstructures and phase identification of CB-template and final SiC ceramics.The infiltration mechanism of liquid Si into charcoal and the basic properties of cellular SiC were also given.The results showed that CB-template was amorphous carbon materials.Final cellular SiC was composed of the major phase ?-SiC and a little unreacted carbon.Compared to charcoal,cellular SiC possessed higher mechanical properties.The improvement of the mechanical properties of materials was mainly caused by the following factors:one was the conversion of carbon fibres into SiC fibres,and the another was the volume expansion during CB-template-to-cellular SiC conversion,which inhibited the initiation and propagation of cracks and made cracks deflect.

Abstract:Microhardness testing was conducted on a series of TiCN-based cermets with different contents of metallic binders (5 binders, Mo?Ni=2?1) in the applied load range from 0.49 N to 9.8 N. Significant indentation size effect in the measured microhardness was observed for each test sample. Based on the energy-balance consideration, a new theoretical explanation is presented for the indentation size effect of microhardness of test sample. It is shown that only part of the work done by applied load has been transformed into the energy to cause the irreversible volume deformation of material during indentation. The extra dissipation of the work done by applied load is the main cause for decreasing tendency of microhardness with increased indentation size. The load-independent hardness was found to decrease with the increasing metallic binder content. This can be attributed to the fact that the hardnesses of metallic binders are lower than that of the TiCN matrix.

Abstract:TiB2-Cu-Ni five-layer metal-ceramic functionally graded material (FGM) was produced by self-propagating high- temperature synthesis (SHS) under the conditions of pseudo hot isostatic pressing (PHIP). The microstructure and composition of the FGM before and after test were examined by SEM and EPMA etc. The FGM was heated for 20 seconds by plasma torch arc heater to investigate thermal shock resistance and ablation behaviour. The results show that the stacked interface between layer and layer of FGM is obscure, which shows that the bonding between layer and layer is good. The FGM did not burst apart when the surface temperatures of FGM increased and went down drastically in a very short moment. Moreover, no apparent cracks were found on the ablation surface of FGM. These results show that the thermal shock resistance of FGM is excellent. The mass loss of FGM after ablation test is only 0.5 g, which shows that the resistance to ablation and erosion of FGM is good. The ablation mechanisms of the material are volatilization of metal binder, hot chemical ablation and mechanical erosion. This FGM can be used widely as nozzle and throat in the solid rocket motor.

Abstract:Photo-catalytic nano titanium dioxide film has been prepared by electrochemical oxidation process. The microstructure and grain morphology in the film are characterized by TEM and XRD. The photo absorption character of the film is measured using spectrometer. It shows that porous amorphous titanium dioxide films are formed by the electrochemical oxidation process in the dielectric solution at an applied voltage and temperature. The amorphous film transforms into nano crystallized titanium dioxide film with anatase structure by means of heat treatment. The oxidation current density decrease with time increase at the voltage of 0~80 V in logarithm law. The grain size in the film is about 20 nm~40 nm. The film has high photo catalytic activity as demonstrated by the degradation test of acid red B in dye solution.

Abstract:用鋯鹽的前驅物(ZrO(OH)2)膠體與氯鉑酸銨均勻混合．經(jīng)過高溫燒結．得到納米ZrO2均勻分布于鉑的坯料，再通過壓力加工方法制成納米氧化锫/鉑復合材料(納米ZrO2／Pt)的試樣。用金相顯微鏡，掃描電鏡(SEM)觀察發(fā)現(xiàn)，納米ZrO2顆?？擅黠@細化基體鉑。納米ZrO2/Pt復合材料的拉伸斷口形貌也與純鉑明顯不同。在高分辨透射電子顯微鏡(HREM)下觀察可見，ZrO2顆粒周圍鉑原子排列發(fā)生了扭曲，由此導致鉑的力學性能發(fā)生很大變化．納米ZrO2/Pt復合材料的抗拉強度(σb)達470MPa．1400℃下的拉伸強度(σb)達15MPa，斷裂伸長率(δ)為20％，硬度(HV)為940MPa．分別是純鉑的3．6倍 10倍，0.5倍和2．3倍。

Abstract:The properties of PW-EVA-HDPE binder with the addition of MW were studied. It shows that the addition of MW from 1% to 30% (mass fraction) causes an increase in the tensile strength and a decrease in shrinkage of the binder. After blending PW with MW, the crystallation behavior of wax matrix changes, that is resulting in fine grain for the binder and more isotropic microstructure for the feedstock. The powder loading capacity increases and the feedstock becomes more homogeneous. The reason of the modification is also discussed.

Abstract:針對鈦齒表面的氧化滲透問題，配制新型涂料，用熔模鑄造法原位制取鈦片試樣模擬鈦齒生產(chǎn)過程。利用能譜(EDX)和X射線衍射(XRD)分析鈦片的化學組成和物相，普通金相顯微鏡觀察顯微組織。結果表明，配制的新型涂料能將鈦片表面氧化滲透層的厚度降至50μm左右，鈦片的滲入元素為鎢和釔。顯微硬度分析表明，鎢的滲入惡化了鈦片的機械性能和使用性能，在蠟模表面均勻涂敷涂料可消除釔的滲入。鈦片表面的氧化滲透是由鑄造過程中熔鈦與涂料在界面處發(fā)生冶金反應的結果。

Abstract:Pure Indium oxide powder was synthesized by chemical precipitation. In2O3 based gas sensing materials doped with noble metal catalyst were made by impregnation. The phase composition of powders was determined with XRD. The gas sensitivity of these side-heated gas sensors were tested in static state by using RQ-2 gas sensitive behaviour analyzer and ploted the curves of gas sensltivity against temperature for several kinds of gas. The results showed that In2O3 based gas sensors can be used to detect gas selectively or generally because of its high gas sensitivity, proper resistance and quick response and recovery.

Abstract:采用溶膠-浸漬法，成功地在三維編織碳纖維的纖維表面涂覆SiO2，并通過碳熱還原反應制得厚度約為0．55gm的SiC涂層。研究了涂層／編織碳纖維(復合纖維)氧化反應的動力學和反應機理。結果表明：涂層能明顯提高編織碳纖維的抗氧化性能：復合纖維的氧化反應過程可以分為2個階段：第1階段為反應控制；第2階段為擴散和反應共同控制。

Abstract:通過對某種鑄態(tài)和預淬火態(tài)亞共析U-Nb合金樣品的900℃等溫淬火實驗，利用金相顯微鏡(OM)，透射電鏡(TEM)和X射線衍射(XRD)等方法研究了單靠熱處理工藝細化該種鑄態(tài)合金晶粒的可行性。實驗結果表明，由a y1-2兩相組成的鑄態(tài)樣品在a y1-2→y1等溫轉變過程中沒有明顯的重結晶行為，y1新相的晶粒特征表現(xiàn)為原y1晶界的平直化遷移，因此淬火后晶粒不能細化；由單一a″相組成的預淬火態(tài)樣品在a″→y1等溫轉變過程中則發(fā)生完全重結晶，等溫0．25h能使晶粒尺寸減小1倍。分析認為，該種鑄態(tài)合金通過預淬火處理使晶格缺陷增多，以及所生成的單一a″相中存在大量的孿晶結構降低了等溫轉變時y1新相的形核能導致了a″→y1等溫轉變發(fā)生重結晶。結論認為，采取兩次淬火的熱處理方法可以細化該種鑄態(tài)亞共析U-Nb合金晶粒。

Abstract:The phases formed by erbium in alloys with 5.6%Zn, 1.9% Mg, 1.6% Cu,1.0% Li,0.3% Er(wt%) is investigated by TEM. Most of erbium is formed with aluminum to Al3Er phases which look like block, dot, lath or worm. Some of Al3Er phases are coherent with alloys matrix, and fine Al3Er phases can be sites for ? (MgZn2) heterogeneous precipitation. Saturated erbium is segregated to grain boundary seriously and there is small Al3Er phase in grain boundary, where precipitates are not continuous.

Abstract:測量和比較Zr-4合金樣品分別在400℃，10.3MPa過熱水蒸汽，0．01mol／L和0．04mol／L的LiOH水溶液中腐蝕后氧化膜／金屬界面處氧化膜內的壓應力，發(fā)現(xiàn)在0．04mol／L LiOH水溶液中腐蝕樣品的壓應力始終低于在0．01mol／L LiOH水溶液中腐蝕的樣品，也始終低于在400℃水蒸汽中腐蝕的樣品；0．01mol／L LiOH水溶液中腐蝕的樣品，其界面處的壓應力在氧化膜達到一定厚度后也低于在400℃水蒸汽中腐蝕的樣品。這表明一定濃度的LiOH水溶液在氧化膜生成過程中會降低氧化膜中的壓應力，LiOH水溶液濃度越高，這種作用越明顯。

Abstract:Ce0.67Tb0.33MgAl11O19: Gd3+ has been synthesized by processing of sol-gel, the influence of Gd doping on fluorescence of Ce0.67Tb0.33MgAl11O19 was investigated by changing the concentration and the substituted object of Gd3+ ion. The effects of substituting a part of Ce and a part of Tb with Ga on fluorescence of Ce0.67Tb0.33MgAl11O19 was studied respectively. Gd3+ transfers the energy absorbed by Ce3+ to Tb3+ efficiently, so the fluorescence intensity of Ce0.67Tb0.33MgAl11O19 changed less when Gd3+ is doped into Ce0.67Tb0.33MgAl11O19, even enhanced to some extent, And the emission color of Ce0.67Tb0.33MgAl11O19 will change a little.