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Abstract:研究了鋁合金表面激光熔覆Fe-Al青銅層的組織結構，結果表明，熔覆層的組織結構為孿晶結構的α-Cu+顆粒狀(Cu, Fe, Si)

Abstract:實驗結果表明，較慢的熔化生長速度有利于改善YBCO晶體的形貌并提高其磁懸浮性能。但無論怎樣改善工藝都很難得到單疇的YBCO大塊超導材料。為此引進了Sm

Abstract:The formation and transformation in (Bi,Pb) 2Sr 2CaCu 2O x have been studied from the point of view of growth kinetics. The component, reaction products and microstructures were analyzed by differential thermal analysis (DTA), XRD, SEM and energy dispersive x ray analysis(ED). The results show that the formation process of (Bi,Pb) 2212 phase follows the rules of solid reaction kinetics. For the formation of textured (Bi,Pb) 2212 phase it is advantageous to choose a very high degree of supercooling and relatively long heat treatment time.

Abstract:采用Ｘ射線粉末衍射和Ｒｉｅｔｖｅｌｄ全譜擬事分析，詳細地研究了Ｚｒ（Ｍｎ１－ｘＮｉｘ）２（ｘ＝０．４０～０．７５）三元Ｌａｖｅｓ相貯氫合金中形成Ｚｒ－Ｎｉ相的類型及其晶體結構。實驗結果表明：Ｚｒ－Ｍｎ－Ｎｉ合金中出現(xiàn)的Ｚ４－Ｍｎ－Ｎｉ合金中出現(xiàn)的Ｚｒ－Ｎｉ相包括ＺｒＮｉ、Ｚｒ９Ｎｉ１１和Ｚｒ７Ｎｉ１０３類，ｒ－Ｎｉ相類型與合金中的Ｎｉ含量有關。其中，ＺｒＮｉ相在ｘ＝０．４０～０．５０范圍內出現(xiàn)，Ｚ

Abstract:A new predicting methodology for the time temperature transformation diagrams of medium carbon multicomponent alloy steels is proposed. Some critical transformation points used to model the time temperature transformation diagrams of multicomponent alloy steels are given as a function of alloy chemistry. It has been found that the bay between two C curves(pearlite and bainite) can be predicted correctly in terms of a precisely calculated B s temperature. The commercial application potential of this approach to the design of new multicomponent alloy steels is also discussed in detail

Abstract:研究了鋯金管材中氫化物的生長方式。結果表明：氫化物片（條）是在晶界上生長，并且以尖端延伸的方式向前發(fā)展。氫化物片的厚度近似一常數(shù)值，與氫含量（滲氫量）沒有對應關系。氫含量的增加只增加化物片的數(shù)量。同時分析了造成氫化物這種生長方式的原因。

Abstract:應用三元擴散偶技術測定Ｎｉ－Ｒｅ－Ｔａ三元系１４７３Ｋ的等溫截面。用電子探針微區(qū)成分分析方法對Ｎｉ－Ｒｅ－Ｔａ三元擴散偶進行是得Ｎｉ－Ｒｅ－Ｔａ三元系在１４７３Ｋ下生成ｉ３Ｔａ、Ｎｉ２Ｔａ、ＮｉＴａ、ＮＩＴａ２和ｘ相５個擴散層，在擴散 未發(fā)現(xiàn)三元化合物。

Abstract:The relation of fracture lifetime to stress and temperature has been investigated for two low carbon manganese steels in air and H 2S, The influence of hydrogen on the fracture activation energy is studied. The results show that hydrogen reduces the fracture activation energy by 74%, that is, atomic binding force decreases.

Abstract:The distribution of T 1 precipitates at the subgrain boundaries and the nucleation of secondary precipitates in the alloy aluminum lithium 2090 have been studied using TEM. The results show that the aspect ratios of the T 1 phase particles which precipitate at the subgrain boundaries is similar to or even smaller than those of nearby T 1 phases, indicating limited coarsening of the T 1 phase. It is calculated that this result conforms to the Perovic criterion, i.e. that it is necessary to balance the elastic interaction energy among the T 1 precipitates in order to stabilize the distribution of the T 1 precipitates. Small T 1 precipitates always appear at the intersection between existing T 1 phases where the nucleation energy of the T 1 phase is lower

Abstract:The rolling process in the 4 roll MK 150/250 cold rolling mill is discussed and analysised. Considered are the pass schedule and the design of the assistant guide plate for Ti bars, ideal square, rectangular and round Ti bars have been obtained. Based on experimental results and theoretical analysis, the influence of rolling load on the tensile strength and elongation of the bars is discussed in detail.

Abstract:The effects of formation pressure, sintering and measurement conditions (in air or in vacuum) on electrical conductivity are studied by means of the measurements of DC voltage current characteristic. Experimental results are explained using the double depletion layer model.

Abstract:探討了循環(huán)熱處理技術在細化ＴｉＡｌ合金晶粒方面的應用。研究表明，粗大的鑄態(tài)組織）約５００μｍ的全層狀組織）經(jīng)塊型轉變預處理后，在α轉變溫度進行６次以上的快速加熱－冷卻處理，可以顯著地細化晶粒。由此還可以制備出２０μｍ的細小全層狀組織。晶粒細化的原因是進行快速循環(huán)相變破壞了組織跗以及新舊閏向關系。影響細化效果的主要因素有；加熱速度、保溫時間、冷卻速度和循環(huán)次數(shù)。

Abstract:The distribution and function of rare earths in a rare earth silver alloy have been studied by means of metallographic examination, electron probe microanalysis and hardness measurement. It has been found that the rare earth compounds distribute in the dendrite grain boundaries of the cast silver alloy. The rare earth compounds congregated in the grain boundaries remarkably result in pronounced grain boundary strengthening, and small amount of rare earth compounds within the grains play a role in solution strengthening. The crushed rare earth compounds in the strong deformed silver alloy lead to a cluster structure after annealing. "Double rare earths", i.e. a pair of similar rare earth elements distribute themselves in similar ways within the silver alloy. If the natures of two rare earth elements are different from each other, their functions are complementary, and the performance of the silver alloy is improved. The addition of yttrium to silver improves work hardenability and high temperature oxidation resistance; further improvement is obtained when yttrium and light rare earth elements are added together.

Abstract:It is difficult to manufacture metal foams using electrical resistivity as a control parameter and due to problems associated with simultaneous production and resistivity measurement. In this paper, some new theoretical formulas to describe the resistivity of highly porous metals are established. An approach is presented for calculation of the electrical resistivity of high porous metal foams as a function of porosity, This simple and convenient method enables the design of porous materials and the control of the electrical resistivity of metal foams.