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Abstract:Research and development of 2:17 type SmCo permanent magnets are reviewed. Considered are four magnets types : high temperature magnets, super-low temperature coefficient magnets, the radially oriented and multi-polar rings, high electricity insulation magnets. Manufacturing techniques described include: powder metallurgy (sintering), reverting-diffuse and quenching-bonding. The cellular microstructure was characterized, and the effects of components on microstructure were discussed. The coercivity mechanism over a wide temperature range was considered and directions for future research discussed.

Abstract:The preparation of nanostructured materials is discussed in the light of previous techniques used for the preparation of nano-scale TiO2. Almost all methods for successfully preparing nano-structured materials can be divided into two categories depending on the sizes of the interacting particles; such processes are designated coacervation and dispersion. These two processes not only provide the new way to design the new type materials but also boost materials processing science to a new level.

Abstract:Much research worldwide is concentrated on nano-cemented carbide due to its excellent properties and promising market prospect. This paper reviewes some developments in nano-cemented carbide. New fast sintering techniques should be employed because the key to obtaining nano-cemented carbide is to control the WC grain growth during sintering.

Abstract:This paper describes the basic concepts, characteristics and material composition of photonic crystals. Self-assembly techniques of preparing three-dimensional semiconductor photonic crystals are introduced in detail. In order to increase the refractive index contrast of the electrolyte, inverted opal is prepared by utilizing a synthetic opal as a template. Finally, we discuss applications of photonic crystals.

Abstract:研究了SiC/TC4和SiC／Ti40復(fù)合材料在不同熱處理態(tài)下的界面行為。結(jié)果襲明，SiC／Ti40復(fù)合材料相鄰兩纖維間存在TiC析出物，在1000℃處理后，TiC析出物消失；2種復(fù)合材料界面反應(yīng)厚度隨處理溫度升高和時(shí)間延長(zhǎng)而增大：SCS-6SiC／TC4和SiC／Ti40復(fù)合材料界面產(chǎn)物均為Ti5Si3。

Abstract:Four kinds of microstructural instability of a TiAl-based alloy during rapid heating cyclic heat treatment were observed: (i) the formation of secondary lamellae, (ii) the spheroidization of primary lamellae, (iii) a discontinuous coarsening at grain boundaries and (iv) nucleation at phase interfaces. By comparing the starting line of continuous heating transformation with that of TTT diagram, the similarity and difference of the microstructure instability during continuous heating and isothermal heating conditions were studied. Ways of avoiding unfavorable microstructural instability were proposed such as: (i) insuring homogeneity of the composition so as to guarantee the identity of transformation temperature in the alloy; (ii) holding at the highest temperature for as short a time as possible.

Abstract:利用X射線衍射技術(shù)測(cè)試了TiC顆粒增強(qiáng)鈦基復(fù)合材料Ti-6Al-4V 7％TiC(質(zhì)量分?jǐn)?shù)，下同)(T64)，Ti-3Al-2．5V 7％TiC(T32)和Ti-6Al-2．5Sn-4Zr-0．5Mo-1Nb-0．45Si 3％TiC(T650)的內(nèi)應(yīng)力。發(fā)現(xiàn)該復(fù)合材料在800℃左右存在一個(gè)應(yīng)力性質(zhì)轉(zhuǎn)變點(diǎn)，即在800℃以上處理，鈦基體感生殘余拉應(yīng)力，增強(qiáng)TiC顆粒感生殘余壓應(yīng)力；在800℃以下處理，應(yīng)力性質(zhì)相反。并且內(nèi)應(yīng)力隨處理溫度升高而增加，由Eshelby模型得出，該轉(zhuǎn)變點(diǎn)和鈦合金基體的相變點(diǎn)有關(guān)。

Abstract:壓縮天然氣(CNG)汽車因其良好的排放特性，正被越來越多的大型城市公交系統(tǒng)使用，但是汽油車輛用尾氣凈化催化荒對(duì)天然氣汽車的主要烴類排放物甲烷轉(zhuǎn)化效率低。針對(duì)天然氣車輛排放物特點(diǎn)，設(shè)計(jì)了天然氣汽車尾氣凈化催化劑，其成分包括稀土金屬和過渡金屬化合物、少量貴金屬氧化物、結(jié)構(gòu)穩(wěn)定劑等。試驗(yàn)結(jié)果表明，在700℃以上，CO和CH4轉(zhuǎn)化率達(dá)到98％以上，催化劑耐高溫性能好，在1000℃，1．5h試驗(yàn)時(shí)間內(nèi)HC和CO轉(zhuǎn)化率達(dá)到99％，此外該催化劑具有一定的抗硫化物中毒能力。

Abstract:The P (MMA-co-St) copolymer containing dysprosium was prepared by the in-situ polymerization of a gel, which was obtained by doping directly dysprosium tri-isopropoxide in the monomer mixtures of methyl methacrylate and styrene (monomer mole ratio was 1:1). The effect of dysprosium tri-isopropoxide on the properties of P (MMA-co-St) copolymer was also studied. It was shown that the linear structure of P (MMA-co-St) containing dysprosium changed into a crosslinked network with increasing dysprosium content, resulting in improvement of properties, such as resistance to heat and solvent, storage modulus and fluorescence strength. Moreover the copolymer is a material with high uniformly distributed rare earth content and improved transparency.

Abstract:The deformation behavior of the alloy Ti14 in the semi-solid state has been studied. The results show that the liquid phase enhances the diffusivity of the constituents. The semi-solid deformation energy is more than that of solid deformation. When the Ti14 alloy is semi-solid deformed, the liquid Ti2Cu phase within grains and grain boundaries grows, thereby forming broadened grain boundaries and network structures.

Abstract:A newly designed Bi2223 tape incorporating an Ag alloy wire in superconducting core is described. It is shown that the new structure considerably improves the superconducting properties of monofilament tapes. The maximum Ic is as high as 75 A, and Jc= 1.6104A/cm2 , increases of 30% over those of conventional superconductor tape. At the same time the mechanical properties of the new Bi2223 tape show considerable improvement.

Abstract:The fractal characteristics of reduced cobalt powders for Powder Injection Molding (PIM), such as powder shape, projection border, and powder surface, are studied. A simple and suitable method which can be used to measure the dimensions of the fractal structure of particle profiles is introduced. An accurate quantitative method for characterizing powders for PIM using fractal geometric nomenclature is given. From the scanning electron micrograph, the fractal dimensions of the projected profile of reduced cobalt powders are calculated using the In Swing Structured Walk technique. Fractal dimensions obtained were in the range of 1.116 to 1.122.

Abstract:A hydroxylapatite (HA) coating was produced by means of bionic mineralizing in a fast calcific solution(FCS)at room temperature. The pH changes of FCS during the deposition process were measured. The supersaturations of various calcium phosphates formed during FCS were compared, during which that of HA was found to be the greatest. Optimnal thermodynamic conditions were important for the formation of HA coatings in the bionic mineralizing process.

Abstract:在IN738鎳基高溫合金上，采用低壓固體粉末包埋滲鋁方法制備鈀改性鋁化物涂層。利用TGA、XRD、SEM以及金相等方法，研究了Pd-Ni-Al涂層在1050℃的高溫氧化行為。結(jié)果表明：與NiAl涂層相比，Pd-Ni-Al涂層表面氧化膜粘附性優(yōu)良，改性涂層的退化相γ'遠(yuǎn)少于普通NiAl涂層，顯示出優(yōu)良的高溫穩(wěn)定性。添加改性元素Pd，提高了鋁化物涂層的抗循環(huán)氧化性能。

Abstract:The microstructure and mechanical properties of AlCuMgAg doped with Ce and Ti were investigated by tensile testing and microstructure analysis. It is shown that Ce and Ti doping increases the hardness and improves the tensile strength. Moreover, the Ce doping can improve the heat resistance of the alloy. By microstructure analysis, it is shown that the kinds of the precipitation- strengthening phases are not changed, although they decrease in size and increase in density. When both Ce and Ti were doped into the AlCuMgAg alloy, a new AlTiCeCu compound that is harder and brittle is formed, the precipitated phases were inhibited, and the tensile strength of the alloy decreased.

Abstract:對(duì)集束拉拔法制備的不銹鋼纖維進(jìn)行150℃~800℃退火熱處理,用VSM測(cè)試熱處理后的纖維磁性,用X射線衍射儀、掃描電子顯微鏡進(jìn)行相分析。結(jié)果表明:熱處理對(duì)304不銹鋼纖維磁性影響較大,2 m的304不銹鋼纖維在180℃附近退火,有回火馬氏體生成,纖維的飽和磁化強(qiáng)度(Ms)增加,此后該溫度范圍內(nèi)退火纖維的Ms降低;400℃熱處理使得纖維矯頑力Hc增加較大,同時(shí)磁能積(Mr×Hc)配合較好,退火后可用作磁性纖維。熱處理對(duì)316 L不銹鋼纖維的力學(xué)性能影響明顯。

Abstract:采用SHS反應(yīng)火焰噴涂工藝在鋼基表面制備了以Al2O3-Al2Cu3相為主的復(fù)相涂層。測(cè)定了涂層的物相組成與組織結(jié)構(gòu)，分析了在熱噴涂工藝條件下涂層的形成過程，實(shí)驗(yàn)了物料預(yù)熱、基材預(yù)熱以及噴涂距離對(duì)涂層組織結(jié)構(gòu)和機(jī)械物理性能的影響規(guī)律。提出：在SHS反應(yīng)噴涂中與物理過程同時(shí)進(jìn)行的化學(xué)燃燒與結(jié)構(gòu)轉(zhuǎn)變過程經(jīng)歷預(yù)熱、SHS燃燒反應(yīng)和結(jié)構(gòu)形成與凝固3個(gè)階段，所得涂層中部分Al2O3以較大尺寸片狀分布于不同Al-Cu區(qū)域邊界，部分以100nm到幾微米的顆粒狀和球狀彌散分布于Al2Cu3基體的內(nèi)部，形成內(nèi)晶型結(jié)構(gòu)；物料預(yù)熱溫度、基材預(yù)熱及噴涂距離等參數(shù)通過影響反應(yīng)轉(zhuǎn)化程度和反應(yīng)能量而對(duì)涂層組織結(jié)構(gòu)和機(jī)械物理性能有較大影響，實(shí)驗(yàn)表明涂層組織與性能在基材預(yù)熱、物料預(yù)熱溫度為250℃以上、噴涂距離在200mm左右時(shí)較為理想。

Abstract:研究了600℃時(shí)Fe-15Ce合金在H2-CO2、H2-H2S及H2-H2S-CO2 3種氣氛中的腐蝕行為，F(xiàn)e-15Ce合金腐蝕后發(fā)生了Ce的內(nèi)氧化或形成了復(fù)雜的腐蝕產(chǎn)物膜，而未出現(xiàn)Ce的選擇性氧化或硫化，這主要是合金中存在著兩相及Ce在Fe中極低的溶解度的結(jié)果。Fe-15Ce合金在本實(shí)驗(yàn)條件下的氧化-硫化腐蝕速度低于相同溫度、壓力下的純硫化。

Abstract:Low temperature combustion synthesis (LTCS) combines the advantage of solution-based processing with that of high temperature self-propagation. The process can be ignited at low temperature and is sustained by a strong exothermic reaction. As presently described the LTCS process was applied to directly synthesize La0.9Sr0.1Ga0.8Mg0.2O2.85 (LSGM1020) ultra-fine powder in nitrate-citric acid solution. The LSGM1020 powder prepared by this method has specific surface area as high as 120 m2/g. The effect of solution initial concentration and pH value on the properties of the final powder was investigated.

Abstract:By mixing NiCl2 and NH4HCO3 solutions at room temperature, NiO nano-particles were synthesized by hydrothermal modification and sintering. The agglomerated amorphous precipitates formed at room temperature were mainly composed of NiCO3. Ni(OH)2 and Ni(OH)2 crystallites and were converted to deposits with higher crystallinity and less content of Ni (OH)2 and H2O after hydrothermal treatment. NiO nano-particles prepared from the hydrothermal deposits were of higher dispersion than those from the amorphous precipitates. The primary thermodynamic calculation in Ni2+-NH3-CO32--H2O system indicated that the rise of temperature is favorable for the release of Ni2+ from the Ni2+-NH3 complex ions, accelerating the formation of NiCO3 and Ni (OH)2. The thermodynamic possibility for the formation of NiCO3 phase increased with the increase of temperature.

Abstract:According to the characteristics of hollow billets, a hot-top electromagnetic continuous casting process is proposed, based on a combination of the hot-top technique and a cold crucible. Sn-4.5%Pb (wt%) was used as the experimental material to study the effect of hot-top and cold crucible outer mould on the distribution of electromagnetic field. The effect of the electromagnetic field on the quality of hollow billets was analyzed. The results indicated that use of the hot-top with screen and cold crucible outer mould, while imposing an electro- magnetic field of 12 kW with the frequency of 2 500, can improve the distribution of electromagnetic field in the mold. In this ways high quality hollow billets can be obtained, whose solidification macrostructure consists of equiaxed grains of high ratio and a smoother surface.

Abstract:研究了鋁板表面前處理以及陽極氧化過程中電解液溫度對(duì)陽極氧化膜層抗熱沖擊性能的影響,并分析了影響機(jī)理.選擇合適的前處理及陽極氧化工藝參數(shù),可以制備具有優(yōu)良性能的"理想"絕緣金屬基板,其陽極氧化絕緣層的電阻率大于1013Ω·cm,擊穿電壓大于600 V,并且能夠抵抗400℃熱沖擊.采用化學(xué)鍍銅結(jié)合電鍍銅工藝對(duì)基板進(jìn)行金屬化布線后,"理想"絕緣金屬基板被應(yīng)用于BGA封裝中.

Abstract:By high temperature pack rolling, the first high-Nb TiAl sheet with the thickness of 2.6 mm has been successfully fabricated on a conventional rolling mill. The overall rolling reduction is about 70%, and the surface condition of the sheet is very good. Microstructure observation indicates that during the high temperature rolling, dynamic recrystallization takes place. But the microstructure is not significantly refined by this recrystallization probably on account of the grain growth that occurs during reheating between rolling passes and final furnaccooling.

Abstract:介紹了1種制備納米釩催化劑的新方法。用TEM，SEM，XRD，DSC等手段研究了納米V2O5溶膠．凝膠，以及活性組分V2O5顆粒在釩催化劑中的形貌、大小和分布等。試驗(yàn)結(jié)果表明，隨著水釩比的降低，納米V2O5顆粒的形狀由針狀、橢球狀向球狀變化：制備納米V2O5溶膠．凝膠適宜的熔化工藝參數(shù)為800℃～860℃，15min～lOmin。采用本工藝方法制備出了含粒徑為30nm～60nm的納米V2O5溶膠-凝膠和納米釩催化劑。

Abstract:A pulp-osseous implant (Ti-6Al-4V) for treating a mobilized periodontal tooth fractured after 15 years of service. The two pieces of implant divided in bone and pulp were extracted and washed by distilled water. The microstructures of the cross sections of both fractured pulp-osseous implant pieces were observed by SEM, and the compositions of the material attached to the implant surfaces were analyzed by EDAX. The fatigue source, slowly and fast developed fatigue stripe is presented were obviously showed on the cross sections of both parts. EDAX showed a higher percentage of Ca, P attached to the bone implant, as compared to that attached to the pulp implant. The fracture of implant in this case was due principally to metal fatigue, and partly caused by a lack of periodontal maintenance.

Abstract:The X-ray stress constants of five crystalline planes of beryllium were measured by using a cantilever beam loading method on X2001 stress analyzer. The results show that the X-ray stress constant of each plane in beryllium is different, so the X-ray stress constant corresponding to a diffraction plane must be adopted in order to acquire the exact stress value on X-ray stress analysis. Because of the rather large penetrate depth of X-rays into beryllium, that effect on X-ray stress constant measurement must be taken into account.