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Abstract:采用試驗和有限元方法研究了熱處理制度對金屬基短纖維復(fù)合材料(MMC)蠕變性能的影響，同時考慮了2種不同熱處理制度和1種鑄造狀態(tài)。試驗結(jié)果表明，MMC的蠕變響應(yīng)與熱處理制度有關(guān)。在相同蠕變應(yīng)力時，鑄態(tài)試樣有最小的最小蠕變應(yīng)變率和最長的蠕變壽命，而熱處理制度2(試樣在550℃保溫24h后隨爐冷卻)具有明顯的最大的最小蠕變應(yīng)變率和最短蠕變壽命，熱處理制度1(試樣在550℃保溫24h后水冷)具有中等的最小蠕變應(yīng)變率和中等的蠕變壽命。用單胞模型結(jié)合有限元方法模擬分析了熱處理的影響，結(jié)果表明，熱處理制度的影響可以歸于熱處理引起的殘余應(yīng)力和殘余應(yīng)變以及它們的歷史，具體可以歸于基體的蠕變耗散能、纖維軸向力和纖維—基體界面力。同時考慮了單胞模型的參數(shù)對上述分析結(jié)果的影響。

Abstract:An unified model is presented to establish the quantitative relations between yield strengths of aged Al alloys containing plate/disc like or rod/needle like precipitates and the sizes, volume percentages of precipitates, The nucleation, growth and coarse of the precipitates are integrated into the age strengthening model based on some acceptable assumptions. The aging strengthening of AA6061 and an Al Zn Mg alloy has been satisfactorily simulated and predicted. Furthermore, the dependence of aspect ratio of plate/disc like or rod/needle like precipitates on aging temperature and processing condition is discussed in detail.

Abstract:運(yùn)用有限元軟件對W／Cu梯度材料進(jìn)行了熱應(yīng)力優(yōu)化設(shè)計，結(jié)果表明，在30MW／m^2的表面熱流負(fù)荷下，經(jīng)過優(yōu)化設(shè)計的W／Cu功能梯度材料有較好的熱應(yīng)力緩和效果，與非梯度材料相比等效熱應(yīng)力降低了62．3％，表面工作溫度下降了50℃；與單純金屬W相比，W／Cu梯度材料的表面工作溫度較之大幅度降低445℃。

Abstract:用Al／Ti／Al復(fù)合層作連接材料，通過連接溫度下原位生成金屬間化合物真空連接Si3N4陶瓷。研究了Al與Ti的厚度匹配和工藝參數(shù)對接頭顯微組織及其強(qiáng)度的影響和接頭的形成過程。結(jié)果表明：當(dāng)原位生成的連接層金屬組織為Al3Ti／Ti／Al3Ti時，由于純金屬間化合物Al3Ti脆性大，且其與剩余Ti片的結(jié)合強(qiáng)度低，陶瓷接頭強(qiáng)度低；當(dāng)連接層金屬組織為大量Al3Ti顆粒加少量Al基固溶體時，連接層金屬能獲得良好的強(qiáng)化效果，與用純Al連接的接頭相比，接頭室溫和高溫強(qiáng)度顯著提高。Al與Ti的厚度匹配和連接參數(shù)適當(dāng)時，接頭室溫和600℃剪切強(qiáng)度可分別達(dá)到89．4MPa和29．7MPa。

Abstract:以有機(jī)基流延工藝制備出了不同Ni含量的NiO／Sm0.2Ce0.8O1.9(NiO／SCO)燃料電池陽極支撐體膜。研究了制備工藝條件和Ni含量等因素對陽極膜微結(jié)構(gòu)和性能的影響。試驗結(jié)果表明：NiO／SCO流延生坯的燒結(jié)溫度對最終陽極燒結(jié)體的孔隙特性有著決定的影響；為獲得具有較高孔隙率和一定孔徑分布的陽極燒結(jié)體，生坯的燒結(jié)溫度應(yīng)不超過1350℃；此外，不同含Ni量陽極流延生坯的燒結(jié)行為及燒結(jié)體的性能也存在明顯的差異，在相同的燒結(jié)溫度下，高含Ni量陽極燒結(jié)體的孔隙率和孔徑都明顯小于低含Ni量的燒結(jié)體，其晶粒的平均尺寸則增大。對不同溫度下Ni／SCO陽極電導(dǎo)率的測量結(jié)果則表明，Ni／SCO陽極的導(dǎo)電性能也與其Ni含量和制備工藝有著密切的關(guān)系。

Abstract:在激光掃描涂覆Al-Ti-C活化粉料層的鋁合金試樣過程中，突然停止激光發(fā)射，以在激光束前面形成合成反應(yīng)過程中不同階段所產(chǎn)生的組織，判斷所發(fā)生的化學(xué)反應(yīng)，即先發(fā)生3Al Ti→Al3Ti反應(yīng)，形成塊狀A(yù)l3Ti；以后再發(fā)生Al3Ti C→TiC 3Al反應(yīng)，形成大量TiC顆粒。將實(shí)驗與數(shù)值模擬相結(jié)合，采用試錯法求得：3Al Ti→Al3Ti的反應(yīng)溫度為650℃，Al3Ti C→TiC 3Al的反應(yīng)溫度為810℃。

Abstract:It was found that a homogeneous and porous titania layer containing Ca and P was formed and converted into a duplex oxidation layer with hydroxyapatite crystallography by the micro arc oxidation of titanium in calcium phosphate electrolyte. The layer morphology and phase composition were not significantly changed by the Ca concentration. Only the concentration of Ca2+ions in solution, the related Ca and P content and the Ca/P atom ratio in the layer increase with increase of Ca concentration in the lower concentration of Ca. It was noted that the HA crystal morphology, the phase ratio and the Ca/P ratio vary with the hydrothermal temperature and Ca concentration of the electrolyte. The HA crystals can be fined by shortening the hydrothermal time. The above results contribute to the optimization of the composition and morphology of the TiO2/hydroxyapatite composite layer on biomedical titanium.

Abstract:The processes of permeation and diffusion of hydrogen in Ti and Ti alloys can be described into three styles: the hydrogen permeating into Ti matrix and dissolved from and titanium hydride diffuses into Ti matrix under a hydrogen pressure; the hydride diffuses with the dislocation movement; and the titanium hydride forms and moves.

Abstract:為探討晶粒尺寸變化對三元復(fù)相合金氧化行為的影響，采用機(jī)械合金化制備了納米晶三元Cu-20Ni-20Cr合金，并對比研究了該合金與同成分的鑄態(tài)合金在700℃～800℃，0．1MPa純氧氣中的氧化行為。結(jié)果表明，鑄態(tài)合金表面沒有形成連續(xù)的Cr2O，保護(hù)膜，而是形成了含有所有組元氧化物及它們復(fù)合氧化物的復(fù)雜氧化膜結(jié)構(gòu)。納米晶Cu—20Ni—20Cr合金在700℃時合金表面形成了連續(xù)的Cr2O3氧化膜，而800℃時雖沒有形成Cr2O3外氧化膜，但氧化膜規(guī)則平坦，外層是CuO，中間層是Cu2O，NiO和Cr2O3組成的混合氧化物區(qū)，內(nèi)層則形成了一薄但不連續(xù)的Cr2O3層。晶粒細(xì)化降低了合金表面形成Cr2O3氧化膜所需活潑組元Cr的臨界濃度。

Abstract:通過對工業(yè)生產(chǎn)的7475鋁合金加入不同含量的鈹，研究了鈹對合金的再結(jié)晶動力學(xué)及時效行為的影響。實(shí)驗結(jié)果表明：加入0．023％Be能有效地提高7475鋁合金的再結(jié)晶溫度，降低再結(jié)晶速度，使合金的晶粒得到細(xì)化，且硬度值仍高于不含鈹?shù)暮辖?；鈹含量?．7％時，上述影響減弱。鈹能有效地降低7475鋁合金的時效硬化時所需時間，同時提高了合金的硬度值，HB最高可達(dá)1400MPa。借助電子衍射分析，觀察并討論了合金中的析出相η′相、β相與基體間的位相關(guān)系的變化和差異。

Abstract:采用引入有機(jī)添加劑的超強(qiáng)堿共沉淀法可制備出粉末粒子尺寸為10nm左右的高純納米多晶氧化鋯粉末。通過控制適當(dāng)?shù)墓に嚄l件，得到了室溫穩(wěn)定的納米四方／立方多晶氧化鋯粉末。用X射線熒光光譜、X射線衍射、透射電鏡、粒度分析儀等手段對粉末性能進(jìn)行了表征。實(shí)驗結(jié)果表明：超強(qiáng)堿共沉淀法所制備的粉末具有純度高、氯離子等雜質(zhì)少等特點(diǎn)；該粉末在室溫和小于873K熱處理時，均以穩(wěn)定的立方或四方相存在；經(jīng)873K處理的粉末粒子尺寸為10nm左右；在1123K處理后，形成固溶完全的穩(wěn)定納米四方多晶氧化鋯粉末，粒子尺寸小，分散性好，粒度分布窄。與其它濕化學(xué)方法相比，添加聚合物的超強(qiáng)堿共沉淀法具有工藝操作簡單、節(jié)約資源和環(huán)境污染小的優(yōu)點(diǎn)。

Abstract:采用Ti，Al和C元素粉末為反應(yīng)物原料，通過燃燒合成法首次成功地制備出了單相三元碳化合物Ti2AlC1-x。實(shí)驗結(jié)果表明：若以“理想”晶體結(jié)構(gòu)化學(xué)式Ti2AlC化學(xué)計量比為起始反應(yīng)原料配比，燃燒產(chǎn)物主晶相為Ti2AlC2；以缺碳的非化學(xué)計量比(Ti2AlC1-x)為反應(yīng)原料配比，即Ti：Al：C=3：1．5：1=2：1：0．7(摩爾比)，得到單相的燃燒產(chǎn)物Ti2AlC1-x。從熱力學(xué)原理的角度探討了不同原料摩爾配比對燃燒產(chǎn)物相組成的影響機(jī)理。

Abstract:P hydroxybenzoate esters were synthesis using ethanol, propanol, butanol and p hydroxybenzoic acid as reactants, and reaction conditions. It is shown that TiSiW12O40/TiO2 is an excellent catalyst for the synthesis of p hydroxybenzoate esters, and that the optimal reaction conditions are 4:1 for the molar ratio of alcohol to acid, 2.0%of total reactant mass for the catalyst, and 2 h for the reaction time. Under these conditions, yields of 87.5%, 89.2%and 91.1%can be reached for the ethyl ester, propyl ester, and butyl ester, respectively.

Abstract:A MoSi2 SiC p composite was prepared by a reactive sintering without pressure. The results showed that a dense MoSi2 SiC p composite can not be made directly from the molybdenum and silicon powders reacted with carbon powder, but from the alloyed MoSi2 powder reacted with silicon and carbon powders. The strength and electrical resistivity of MoSi2 SiC p composite with various silicon carbide contents were measured and analysed at the same time. The results showed that the highest strength was 157 MPa and the electrical resistivity increased with the increase of SiC content.

Abstract:用非平衡交流微弧氧化法于Na2SiO3-KOH-(NaPO3)6溶液中在Ti6Al4V表面形成氧化物陶瓷膜。分別用掃描電鏡、電子探針及X射線衍射研究了陶瓷膜的組織形貌、元素分布和相組成。相對致密均勻的膜層主要由TiO2(鈣鈦礦相及金紅石相)及非晶相組成。厚約20μm的膜可分為3層：過渡層、致密層與疏松層。電解液所含元素Si，P進(jìn)入到膜層中，表明電解液組元急烈參與微弧氧化反應(yīng)，這為通過選擇電解液來設(shè)計膜層的相組成進(jìn)而對膜層進(jìn)一步改性提供途徑。

Abstract:The morphology and deformation behavior of the clustered, scattered and isolated hydrides in recrystallized Zr 4 have been studied by in situ SEM. It is shown that the hydride can deform plastically together with the matrix at room temperature. The deformation behavior of hydrides depends on their morphology. The clustered hydrides fracture at relatively low strain levels while the sparse hydrides are more ductile and usually fracture at a quite large strain. The isolated hydride has the best deformation capability and is difficult to fracture.

Abstract:用Ti—Cu—Ni，Ti-Cr-Zr釬料在TIG電弧加熱條件對TA2和Ti—6Al—4V鈦合金進(jìn)行釬焊。結(jié)果表明：用Ti—Cu—Ni釬料釬焊TA2和Ti—6Al—4V鈦合金的搭接接頭強(qiáng)度分別是418．3MPa和439．6MPa；用Ti—Cr—Zr釬料釬焊TA2和Ti—6Al—4V鈦合金的搭接接頭強(qiáng)度分別是575．2MPa和656．1MPa。對Ti-Cu-Ni釬料／母材界面分析認(rèn)為固液異分化合物η相((Cu，Ni)Ti2)生成時呈筍狀生長，嵌入釬縫對釬縫的強(qiáng)度提高有利。對Ti-Cr-Zr釬料／母材界面分析，認(rèn)為主要是固溶體β-Ti(Cr)存在提高了釬縫強(qiáng)度。

Abstract:Silver tin oxide(AgSnO2) was fabricated using the conventional powder metallurgy(PM) and a new reactive synthesis(RS) method. Electrical conductivity measurement and X ray diffraction analysis were carried out on bulk AgSnO2 microstructures were determined by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) on the bulk AgSnO2 and its cold drawn wire. The results show that SnO2 particles with finer size and fresh interface can be formed in silver matrix as a result of the fabrication of AgSnO2 electrical contact materials by reactive synthesis. micrometer size tin oxide particles were assembled from nanometer scale particles during the RS process. Compared to conventionally PM processed, AgSnO2 electrical contact materials those fabricated by the RS process have a higher conductivity. and workability as a result of a change of combination states of silver and tin oxide.

Abstract:為了研究Nb離子注入對Zr-4合金電化學(xué)腐蝕性能的影響,對Zr-4合金試樣表面進(jìn)行不同劑量的Nb離子注入并測定其在1NH2SO4水溶液中的極化曲線,然后使用掃描電子顯微鏡(SEM)對極化實(shí)驗后的試樣表面形貌進(jìn)行了觀察。結(jié)果表明,Nb離子注入能夠改善Zr-4合金的耐腐蝕性能,而且改善的程度與注入離子的劑量有關(guān)。同時使用X射線光電子能譜分析(XPS)對試樣的表層成分和價態(tài)進(jìn)行了分析,發(fā)現(xiàn)在注量為5×1016ion/cm2和1×1017ion/cm2的條件下,Nb和Zr在試樣表層以Nb2O5和ZrO2的形式存在;而在注量為2×1017ion/cm2的條件下,則以Nb2O5,NbO和ZrO2的形式存在。