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Abstract:對(duì)銅中添加鈮的不同組份Ｃｕ－Ｎｂ鑄錠的冷加工性及經(jīng)不同冷拉拔比（ε）Ｃｕ－Ｎｂ復(fù)合體的抗拉強(qiáng)度（σｂ、σ０．２）與導(dǎo)電性能等方面進(jìn)行了研究。試驗(yàn)結(jié)果表明：在含Ｎｂ量＜２０Ｖｏｌ．％的Ｃｕ－Ｎｂ鑄錠，其塑性優(yōu)良，可進(jìn)行冷加工；當(dāng)冷拉拔比為６時(shí)，Ｃｕ－１８Ｖｏｌ．％Ｎｂ和Ｃｕ－２０ｖｏｌ．％Ｎｂ兩種復(fù)合體的極限強(qiáng)度與屈服強(qiáng)度分別達(dá)７００～８００ＭＰａ和６００～７００ＭＰａ；其導(dǎo)電率約為無氧銅的２／３。用金相顯微鏡觀察了Ｃｕ－Ｎｂ復(fù)合體的顯微組織。文中還對(duì)與Ｃｕ－Ｎｂ復(fù)合材料的性能有關(guān)的問題進(jìn)行了討論。

Abstract:The composition of the match welding wire of Ti-75 alloy has been studied.Some properties of the welding joint and the weld line have also been investigated, such as mechanical properties, fracture mechanics, stress corrosion and general corrosion. In addition, welding experiments for the imitative structure component have been carried out. The results show that the chosen composition of the welding wire is reasonable and the synthetic properties of the welding joint are better. That is to say, the wire is an ideal match welding solder.

Abstract:he methods of physical metallurgy have been reviewed for various kinds of typical materials of precious metals, and the physicochemical fsctors effecting the quality of materials have been also discussed. In addition, so me new metallurgical processes have been actively co nsidered.

Abstract:n this paper, two attractive features of the recent advances in Hard and Soft magnetic materials are reviewed. The nitrogenation of Sm2Fe17 has produced a promising new hard magnetic magerial with a curie temperature and magnetic anisotropy higher than Nd2Fe14B. For the soft magnetic materials, the classical technique for microstructure of big grains has been broken by the success in the development of Fe - matrix nanocrystalline due to its high magntization and high permeability. These and other recent advances in hard and soft magnitic materials ard briefly reviewed.

Abstract:n this Paper some factors concerned in modelling kinetics of zircaloy cladding oxidation under in-pile meltdown condition and some related modes have been discussed.

Abstract:n the present paper, the recent adrance in spectrophotometric analysis of titanium in metal and alloy is described.

Abstract:he Oxygen absorption processes in highly aligned YBaCuO samples in air and in pure oxygen were studied at several constant temperatures. The process can be expressed in two steps: a chemical reaction controlled step and a diffusion controlled step. The kineticequations are as follows, respectively:The activation energy was calculated by using an Arrhenius equation. The technicalconditions of heat treatment for oxygen absorption of highly aligned YBaCuO crystals are discussed.

Abstract:The interfacial phase of Ti/ TiCp composite was measured to be Ti2C by TEM and EELS. The cell of Ti2C and the position corrdinates of Ti and C atoms were determined with the knowledge of electron diffraction and crystallography, the regulations of carbon vacancy order distribution were also discussed. There are 48 atoms in Ti2C cell: 32 Ti atoms and 16 C atoms. The Ti atoms occupy the 32 e sites (x is 3/8 or 7/8)and the C atoms occupy the 16 c or 16 d sites in Ti2C space group Fd3m. The C vacancy arrangement is in order in the F111G C layers. The F 111G C layers with 3 / 4 and 1 / 4 occupancies were arranged alternately. There are 6 Ti layers arid 6 C layers during one period in the direction of <111>, the sequence is:

Abstract:he effecting of quenching on the performance and structure of WC-Co cemengted carbides has been studied. It has been explored that the quenching of WC-Co cemented carbides had changed not only their binder composition and stress condition but also their microstructural parameters, the effecting extent is related to the to the WC grain size in the alloy. The stability of quenching for the WC - Co alloy in practical operation has been investigated showing the practicality of quenching for WC-Co alloy.

Abstract:aMnO3 ultrafine powders were prepared by pyrolysis of amorphous citrate.XRD indicates the single phase of LaMnO3 has been synthesized. They are hexagonal in the structure. The experiments show that the mean particle size of LaMnO3 increases greatly with the increase of firing temperatures. The change of the electrical resistivities with the particle sizes has been first studied for the LaMnO3 ultrafine powders. It was found that the electrical resistivites of LaMnO3 at room temperature decrease with the increase of particle sizes, the activated energy for conduction decreases with the decrease of the particle sizes.

Abstract:abrication technology of carbon fiber reinforced aluminium composed by squeeze casting has been investigated. The results show that the squeeze casting technique is a simple and reliable method for making fiber reinforced aluminium composites.

Abstract:研究了高純金中Ｃｏ，Ｆｅ，Ｎｉ，Ｃｒ，Ｐｈ，Ｓｎ，Ｂｉ，Ｍｇ，Ｍｎ．Ａｌ，Ｃｕ，Ａｇ，Ｐｔ，Ｐｄ，Ｒｈ等微量元素的化學(xué)光譜測(cè)定方法。選用二鹽酸肼為還原劑。并對(duì)還原劑濃度、還原酸度、還原及蒸發(fā)溫度對(duì)測(cè)定的影響，以及二鹽酸肼和基體金對(duì)測(cè)定的干擾進(jìn)行了試驗(yàn)。方法適應(yīng)性好，測(cè)定下限為０．１～１μｇ／ｇ。

Abstract:建立了以雙鉑電極作指示電極，于ＫＢｒ─Ｎａ２Ｂ４Ｏ７介質(zhì)中，用Ｃａ（ＣｌＯ）２滴定測(cè)定Ａ１Ｎ、ＴｉＮ、Ｓｉ３Ｎ４、Ｓｉ３Ｎ４／ＳｉＣ材料中氮的方法。本方法對(duì)于２０％－４０％的氮的測(cè)定，標(biāo)準(zhǔn)偏差小于０．２２％，可測(cè)定金屬材料中０．０５％以上的氮。

Abstract:基于在稀硫酸介質(zhì)中鈰（Ⅳ）能氧化甲基紅使之褪色的原理，建立了用分光光度法測(cè)定稀土硬質(zhì)合金中的鈰的操作步驟，并分析了Ｈ２ＳＯ４酸度、共存離子、甲基紅用量等對(duì)測(cè)定的影響。結(jié)果表明：本法操作簡(jiǎn)便，試劑簡(jiǎn)單，可測(cè)定０．０１％～１％的鈰。