电镀铜—镍合金时的阴极行为研究

用线性电势扫描法研究了含有Ｃｕ＾２＋，Ｎｉ＾２＋离子＋柠檬酸钠以及Ｃｕ＾２＋离子＋柠檬酸钠，Ｎｉ＾２＋离子＋柠檬酸的溶液中，铂电极和铜电极上的阴极行为。结果表明：（１）在－０．０７Ｖ（相对Ｓ．Ｃ．Ｅ）左右有铜配离子的还原。此过程受铜配离子的扩散控制。在－０．３０～－０．６０Ｖ之间是铜－镍合金形成区，在－０．７０～０．９０Ｖ之间是镍配离子的还原区。（２）向含有Ｃｕ＾２＋离子，Ｎｉ＾２＋离子的溶液中加     

铝材化学镀镍—铜—磷合金

研究了铝在以次亚磷酸钠为还原剂，柠檬酸钠为络合剂的碱性槽液内化学镀Ｎｉ－Ｃｕ－Ｐ的工艺。分析了影响镀层成分，共沉积过程及镀层与基体结合强度的因素。本文指出，镀液「Ｎｉ＾２＋」／「Ｃｕ＾２＋」在１．２－２０．０范围变化时，可获得含铜（９５－５１）％（ｗｔ）的Ｎｉ－Ｃｕ－Ｐ合金镀层。     

一个与准晶相关的新Al—Cu相

本文报道一个新Ａｌ－Ｃｕ相，具有正交结构，空间群Ｆｄｄｄ，点阵常数为：ａ＝０．８１６６ｎｍ，ｂ＝０．９９９５ｎｍ，ｃ＝１．４１４９ｎｍ，表达式为Ａｌ４３．２Ｃｕ５６．８，该相与Ａｌ－Ｃｕ－Ｆｅ准晶的价电子浓度相同，是一个由ＣｓＣｌ结构衍生的类似相。     

一个与准晶相关的新Al－Cu相

本文报道一个新Ａｌ－Ｃｕ相具有正交结构，空间群Ｆｄｄｄ．点阵常数为：ａ＝０．８１６６ｎｍ，ｂ＝０．９９９５ｎｍ，ｃ＝１．４１４９ｎｍ，表达式为Ａｌ４３．２Ｃｕ５６．８．该相与Ａｌ－Ｃｕ－Ｆｅ准晶的价电子浓度相同，是一个由ＣｓＣｌ结构衍生的类似相．     

超微粉石墨层间化合物CuCl2—NiCl2—GICs合成及电学性能

常规的ＧＩＣｓ合成原料均采用合成石墨或者粒度较粗的天然石墨，这里采用超微粉石墨作原料，进行受主金属氯化物ＣｕＣｌ２－ＮｉＣｌ２－ＧＩＣ的合成研究。使用山东南墅石墨（３０００目）、Ｃｕ－Ｃｌ２和ＮｉＣｌ２（５ｎ：０．５：０．５摩尔比），在５２８℃，真空度１０．３Ｐａ条件下，得到超微粉的ＣｕＣｌ２－ＮｉＣｌ２－ＧＩＣｓ，ＳＴＥＭ单原子能谱扫描结果显示出铜离子和镍离子分布基本均匀，合成的１，２，３和４阶     

熔甩Cu—Co合金薄带的结构,磁性及巨磁阻

研究了熔甩法制备的ＣｏｘＣｕ１－ｘ（０〈ｘ〈０．２０）颗粒合金的结构、磁性以及输运性质，通过Ｘ射线衍射（ＸＲＤ），差动热分析（ＤＣＳ）以及磁性测量，发现造成Ｃｏ－Ｃｕ合金磁性及输运性质变化的Ｃｏ相分离过程，当０〈ｘ〈０．１５时，在４５０℃退火火３０ｍｉｎ的ＣｏＣｕ合金中Ｃｏ颗粒的直径为３．５－４．５ｎｍ。并呈现最大的巨磁阻效应，磁性随析出Ｃｏ颗粒浓度及尺寸的变化与双通道模型的预示一致，粒子界面引起     

Cu—YBaCuO粉末复合材料组织与性能的研究

预期得到了一种具有较高强度而又不降低导电率的铜基粉末复合材料，选用超导陶瓷粉末ＹＢａＣｕＯ为强化相，以冷等静压，热挤压等粉末冶金方法研制了两种（Ｃｕ－５％ＹＢａＣｕＯ）和Ｃｕ－２０％ＹＢａＣｕＯ粉末复合材料，在常温和液氮温度下测试了这两种复合材料的力学性能与导电性能，研究表明，该复合材料的力学性能与导电性能，研究表明，该复合材料低温（７７Ｋ）时的力学性能优于室温，但导电率并没有改善，其原因在于所加     

RS高强Al－Zn－Mg－Cu系合金热处理温度与性能的关系

本文系统研究了ＲＳ高强Ａｌ－Ｚｎ－Ｍｇ－Ｃｕ系合金淬火温度、时效温度与性能关系，同时还分析了合金的微观组织。试验得出在４７０℃淬火峰时效（Ｔ６）的拉伸性能达到σ_ｂ＝７４０ＭＰａ，σ_（０．２）＝７０２ＭＰａ，δ_５＝１０％；双级时（Ｔ７３）可获得σ_ｂ＝６３３ＭＰａ，σ_（０．２）＝６０６ＭＰａ，δ_５＝１１．５％。合金的弥散强化相是Ｃｏ_２Ｎ_９、Ａｌ_３Ｚｒ，沉淀强化相为ＧＰ区、η＇和η。     

浇注温度对定向凝固Al－Cu合金热裂的影响EI

针对空心叶片类定向凝固铸件存在的热裂问题，开展了定向凝固热裂规律的研究。本文选择凝固参数较全的Ａｌ－Ｃｕ系合金，研究了定向凝固工艺参数之一的浇注温度对Ａｌ－０．６ｗｔ％Ｃｕ和Ａｌ－２．０ｗｔ％Ｃｕ合金热裂的影响。定向凝固热裂试验表明，提高浇注温度可以降低Ａｌ－０．６ｗｔ％Ｃｕ合金的热裂程度，但对Ａｌ－２．０ｗｔ％Ｃｕ则无作用。理论分析认为，合金在不可补缩区的冷却速率变化是改变合金热裂程度的重要因素。     

浇注温度对定向凝固Al－Cu合金热裂的影响

针对空心叶片类定向凝固铸件存在的热裂问题，开展了定向凝固热裂规律的研究。本文选择凝固参数较全的Ａｌ－Ｃｕ系合金，研究了定向凝固工艺参数之一的浇注温度对Ａｌ－０．６ｗｔ％Ｃｕ和Ａｌ－２．０ｗｔ％Ｃｕ合金热裂的影响。定向凝固热裂试验表明，提高浇注温度可以降低Ａｌ－０．６ｗｔ％Ｃｕ合金的热裂程度，但对Ａｌ－２．０ｗｔ％Ｃｕ则无作用。理论分析认为，合金在不可补缩区的冷却速率变化是改变合金热裂程度的重要因素。     

用标准加入石墨原子化法测定铝合金电解着色膜中的铜、镍、锡

为了提高铝阳极氧化电解着色膜中铜、镍、锡元素的测试准确性,将标准加入法运用于石墨原子化(GFAAS)中,可有效地抑制共存物的干扰.采用标准曲线法初步确定线性区间,然后确定样品试液的最佳稀释倍数、最佳标准加入系列溶液,最终确定具有较好线性关系的铜、镍、锡标准加入的线性区间(分别为0～0.6 mg/L、0～0.8 mg/L和0～0.7 mg/L).结果表明,在铜、镍、锡共存体中,镍含量的增加可降低铜、锡元素的标准加入校准曲线的线性相关系数.对于成分复杂的样品,标准加入法具有更高的准确性.     

Microstructures and mechanical properties of milled and continuously cast lead sheet Part 1 Microstructures

Abstract

Milled lead sheet exhibits a recrystallised microstructure, the grain size of which decreases with increasing copper content; copper is present as particles of ~1–5μm in length, formed from the initial needles or plates of the cast billet by spheroidisation, or by particle break-up during rolling. A comparison of materials produced by several manufacturers indicates that the copper distribution and final grain size are dependent on the thermomechanical history of the sheet. Direct method sheet exhibits a cast cellular structure within grains which usually extend through the full thickness of the cast sheet; copper is present as a fine dispersion (particles ~0·5 μm dia.) at cell boundaries. The copper distribution in both materials was stable with prolonged heating (100 h at 200°C), but some grain growth occurred in the milled sheet. It was not possible to obtain a fully dispersed eutectic microstructure at the eutectic composition; primary lead dendrites (or cells) were always present. This is thought to be a result of the difficulty of nucleating a copper particle in the very low copper concentration alloys used in this work.

MST/1065     

添加剂对传感器用PCB环氧树脂板真空蒸镀铜层参数优化及结构的影响

为了提高传感器用PCB环氧树脂板的表面性能,利用次磷酸钠体系在其表面进行真空蒸镀铜.选择苯亚磺酸钠(SBS)与聚乙烯亚胺(PEI)作为添加剂来分析其对镀铜层性能的影响,获得更适合真空蒸镀铜工艺的添加剂.研究结果表明:在65℃下持续沉铜0.5 h,综合沉积率以及板面颜色,确定最优含量PEI为16～28 mg/L,SBS为...     

铜氨溶液吸收法测氧过程影响因素分析

介绍了铜氨溶液吸收法测量氧浓度的工作原理、测氧过程和影响因素。通过分析可知,铜氨法测量的混合气中氧气的体积百分比浓度与所处环境的温度、压力无关,对于相同的氧气组成,在不同大气环境下测得的数据应相等。进行氧气浓度测量时,在0~90 mL段,氧气体积百分比浓度测量值小于实际值;在90~99 mL段,测量值等于实际值;在99~100 mL段,测量值大于实际值。     

硅粉表面化学镀铜工艺研究

研究了化学镀法对硅粉进行化学镀铜过程,探讨了甲醛含量、pH值、温度对化学镀铜反应时间及复合粉体颜色的影响和镀层的微观形貌及结构。结果表明：在镀液中,pH值增大、温度升高、甲醛含量增加,可以缩短反应时间,提高镀速。得出最佳工艺条件：甲醛为60～72ml／L,pH值为12～12．5,60℃。所得复合粉体镀覆均匀,晶形良好,没有Cu2O的存在。     

主动围压下岩石的冲击力学性能试验研究

利用具有主动围压加载装置的直径为100 mm分离式Hopkinson压杆（SHPB）试验装置和薄圆形紫铜片作为波形整形器,研究了斜长角闪岩在不同围压等级（0~6 MPa）、不同应变速率（50~170 s-1）下的动态力学性能,并对试验有效性进行了分析。试验结果表明：斜长角闪岩的动态强度增长因子与应变率的对数呈近似线性关系,强度与比能量吸收随应变率的增加而近似线性增加,体现了显著的应变率相关性;在同等级应变率范围内,随着围压的增加,岩石的增强效果与增韧效果逐渐增强;同时发现,在围压作用下,岩石的破坏由拉伸破坏向压剪破坏逐渐过渡和发展。SHPB试验中,近似恒应变率加载时间比例约为69.5 %,能够较好地满足应力均匀分布及近似恒应变率加载要求,表明SHPB试验的有效性和结果的可靠性     

Effect of copper on the electrical properties of K1.6(Mg1−yCuy)0.8Ti7.2O16 ceramics

The electrical conductivity of the K1.6(Mg1–yCuy)0.8Ti7.2O16 ceramics has been investigated as a function of copper fraction (0y1). At the calcination temperature of 1000°C, a tetragonal-single phase was obtained for the all compositions. In the specimens sintered at 1100°C for 4 h, the electrical conductivity of the specimens increased with the increasing copper fraction, y. This result can be explained by the weakness of the K–O bonding and the increase of the bulk density and grain size. For the specimens with copper fraction (0y<0.8), the electrical conduction was developed mainly by ionic conduction while electronic conduction abruptly occurred at copper fraction y0.8. This resulted from the valence transition of copper ions associated with the formation of oxygen vacancies.     

PVC-Cu composites with chemically deposited ultrafine copper particles

PVC-Cu composites with chemically deposited ultrafine (0.1 to 0.3 m diameter) copper particles were prepared by hot-pressing copper-coated PVC powder (–106, +150 m) at 120° C. Metallic copper in fine-particle form was deposited on the PVC particles by reducing an ammoniacal cupric acetate solution with hydrazine at 85° C. The electrical resistivity (d.c.) and transverse rupture strength of these composites were measured. Measurement of electrical resistivity indicated that in these composites copper particle network formation was initiated at a copper content of about 0.2 vol%; with further increase of copper content the resistivity dropped sharply from about 10¹⁴ (for pure PVC) to about 10⁵ MN m^–2 cm at a copper content of about 0.5 vol%. Increase of copper loading beyond 0.5 vol% did not decrease resistivity significantly whereas the rupture strength increased continuously from 120 MN m^–2 (for pure PVC) to a value of about 300 MN m^–2 with 4 vol% copper loading. This high value of resistivity even after copper particle chain formation and the continuous increase of rupture strength, is thought to be due to formation of a thin layer of polymer film between the copper particles introducing a quasi-random character to the otherwise segregated network of copper particles.     

Pt Content Dependence of the Switching Field Distributions of CoPtCr-SiO2 Perpendicular Media Characterized by Subtracting the Effect of Thermal Agitation

The switching field distributions (SFD) of CoPtCr-SiO₂ perpendicular media as a function of Pt content were characterized by subtracting the effect of thermal agitation, and discussed in relation to the microstructure. DC demagnetizing (DCD) magnetization curves and minor dc demagnetizing (M-DCD) magnetization curves were measured at applied field sweep rates of ~10 Oe/s and ~10⁸ Oe/s. We estimated the width of SFD, DeltaSFD, from the difference between the DCD and M-DCD curves, and defined them as DeltaH_r/H_r (at ~ 10 Oe/s) and DeltaH_r ^P/H_r ^P (at ~10⁸ Oe/s). The values of DeltaSFD characterized by subtracting the effect of thermal agitation, DeltaH ₀/H₀, were nearly half those of DeltaH_r /H_r for 10-nm-thick media. DeltaH₀/H₀ was about 0.10 at 10 at%Pt content, and increased as the Pt content increased, reaching 0.17 at 30 at%Pt content. The increase in DeltaH₀/H₀ was probably caused by an increase in the stacking fault density and the formation of fcc layers in the hcp CoPtCr lattice. A simple calculation based on the coherent switching of magnetization revealed that the c-axis distribution results in DeltaH ₀/H₀ of about 0.08, independent of Pt content. These results suggest that the DeltaSFD due to the grain-to-grain anisotropy field variation was small, only 0.02-0.03     

Heat Inputs to Sub-mK Temperature Cryostats and Experiments from γ-Radiation and Cosmic Ray Muons

We measured the spectrum of energies deposited by -radiation, emanating from radioactive materials in the laboratory that houses our mK cryostat, and by cosmic ray muons. This allows us to quantify the heat input that adversely affects the lowest temperature accessible in sub-mK experiments. We use our nuclear stage, stage plate and experimental cell as a prototype model system, and calculate the power deposited due to low energy (below 2.65 MeV) background radiation quanta (~20 pW). This is significantly less than the power (~120 pW) deposited in the nuclear and experimental stages by muons. Installation of a 5 cm thick lead wall around the cryostat reduced the energy due to the flux of quanta by a factor of ~10 to ~2 pW, and the number of quanta by a factor of ~20. The lower energy, soft cosmic ray component was also affected by introducing the same thickness of lead, reducing the overall count of cosmic ray derived particles by ~15% and the heat leak to ~100 pW.