Cu,Mg,Si,La对低成分Al—Cu—Mg—Si合金强度的影响

在正交实验的基础上研究了Ｃｕ、ｇ,Ｓｉ,Ｌａ及形变热处理对低成分铝合金Ａｌ－（０．４５％￣１．４５％）Ｃｕ－（１．１４％￣２．１４％）Ｍｇ－（０．２５％￣１．２５）Ｓｉ－（０￣０．２％）Ｌａ强度的影响。实验结果表明,它们对合金室温抗拉强度影响的主次顺序为：Ｓｉ、Ｃｕ,Ｍｇ,Ｌａ;而形变热处理与常规热处理相比,能提高实验合金的抗拉强度。     

合金元素Cu,Si,Ni对Al基钎料的影响

A1—Si钎料因具有良好的润湿性、流动性、钎焊接头的抗腐蚀性和可加工性，应用非常广泛，但其熔点较高，很难用于低熔点铝合金的钎焊。本文以Cu，Ni作为主要的添加元素，通过正交试验的方法研究了合金元素Cu，Ni，Si对A1基钎料性能的影响。结果表明，随着合金元素Cu，Si的质量分数的增加，其熔点大大降低；同时钎料的铺展性能也有所改善；合金元素对钎焊接头强度的影响规律不明显。     

固态Cu—Al合金中Al活度的测定

用固体电解质电池在1000℃下研究了固态Cu-Al二元系中Al的活度,Al的摩尔分数为0.0234到0.327。     

Al—3.5Cu和Mullite／Al—3.5Cu复合材料的时效析出行为

用差示扫描量热仪（DSC）对Al-3.5Cu合金和莫来石（Mullite)短纤维增强Al-3.5Cu复合材料的时效析出行为进行了研究。结果表明,Al-3.5Cu合金和Mullite/Al-3.5Cu复合材料固溶淬火试样的DSC扫描曲线存在较大不同,GP区形成的溶解的信息在基体合金的DSC曲线上清晰可见,但在复合材料固溶淬火试样的DSC曲线上则很难确认,表明纤维推延或抑制了GP区的形成。θ^〃相和θ′相的析出过程由于纤维的引入而得到明显加快,峰值温度降低,激活能减小,时效析出过程加快。但是,扫描参数选择不当时,容易对析出相的析出过程产生错误判断,应引起重视。     

Zr–(Cu,Ag)–Al bulk metallic glasses

In this paper, we report the formation of a series Zr–(Cu,Ag)–Al bulk metallic glasses (BMGs) with diameters at least 20 mm and demonstrate the formation of about 25 g amorphous metallic ingots in a wide Zr–(Cu,Ag)–Al composition range using a conventional arc-melting machine. The origin of high glass-forming ability (GFA) of the Zr–(Cu,Ag)–Al alloy system has been investigated from the structural, thermodynamic and kinetic points of view. The high GFA of the Zr–(Cu,Ag)–Al system is attributed to denser local atomic packing and the smaller difference in Gibbs free energy between amorphous and crystalline phases. The thermal, mechanical and corrosion properties, as well as elastic constants for the newly developed Zr–(Cu,Ag)–Al BMGs, are also presented. These newly developed Ni-free Zr–(Cu,Ag)–Al BMGs exhibit excellent combined properties: strong GFA, high strength, high compressive plasticity, cheap and non-toxic raw materials and biocompatible property, as compared with other BMGs, leading to their potential industrial applications.     

Interfacial reactions of Sn–Zn–Ag–Cu alloy on soldered Al/Cu and Al/Al joints

This work shows the effect on the soldering process of the addition of Ag and Cu to Sn–Zn alloys. Soldering of Al/Cu and Al/Al joints was performed for a time of 3?min, at a temperature of 250°C, with the use of flux. Aging was carried out at 170°C for Al/Cu and Al/Al joints for 1 and 10 days. During the aging process, intermetallic layers grew at the interface of the Al/Cu joint at the Cu substrate. Intermetallic layers were not observed during wetting of Al/Al joints. On the contrary, dissolution of the Al substrate and migration of Al-rich particles into the bulk of the solder were observed. The experiment was designed to demonstrate the effect of Ag and Cu addition on the dissolution of Al substrate during the soldering and aging processes. In the solder alloys, small precipitates of AgZn₃ and Cu₅Zn₈ were observed.     

Electromigration-induced Cu motion and precipitation in bamboo Al–Cu interconnects

The kinetics of θ phase (Al₂Cu) precipitation in passivated, bamboo Al-0.2 at.% Cu segments was studied in-situ in an SEM during electromigration. The electrical current was used to reversibly transport Cu back and forth along the segment and allowed for a systematic study of Cu diffusion and precipitate nucleation, growth, and dissolution. The observations allowed an independent determination of diffusion with and without an electric current and showed that both interface and lattice diffusion are important in Cu precipitation in bamboo segments. It was also found that a substantial supersaturation of Cu is required to nucleate the θ phase. A simple model for electromigration-induced motion of Cu can be used to explain the data and predicts that an interconnect with Cu both in solution and in periodically spaced precipitates will have optimal reliability.     

Al/Cu/Al接触反应液相行为及其连接

采用模拟的方法,系统研究了Al/Cu接触反应及其液相行为的特点,并运用金属学中表面扩散和晶界扩散等理论进行了理论探讨。研究结果表明,在接触反应中Al/Cu共晶液相的行为包括：一方面液相沿Al基体表面优先反应铺展;另一方面在基体深度方向上也有明显的晶间渗透作用。其中前者可以促进接头间隙内产生均匀的液相填充层;后者则是接头牢固接合的保障。同时为确定Al/Cu/Al接触反应钎焊工艺参数,研究了工艺参数对接触反应中共晶液相铺展行为的影响,结果表明570－580℃的反应温度和15min的保温时间是Al/Cu接解反应钎焊比较适合的工艺参数。在此基础丰,本文采用Cu箔作中间层进行Al的接触反应钎焊,得到良好Al钎焊接头。     

液态Cu和Al的短程有序结构

为了研究液态Cu和Al的短程有序结构,建立了液态微观结构的纳米晶粒模型.根据这个模型,从晶体X射线衍射学的角度出发,通过对一定晶格结构的固态Cu和Al衍射峰进行宽化处理,计算出了它们的液态X射线衍射强度曲线.结果表明,这些强度曲线与实验获得的液态Cu和Al的X射线衍射强度曲线具有较好的一致性,这不仅证明了纳米晶粒模型的正确性,同时也证明了Cu和Al的液态短程有序结构分别是FCC和BCC.     

Cu—Al—Mn低温形状记忆合金

Ｃｕ—Ａｌ—Ｍｎ低温形状记忆合金管子连接件和机械紧固件是目前形状记忆合金最成功的应用，并且几乎都要使用价格昂贵的Ｎｉ—Ｔｉ合金。为了开发廉价的实用形状记忆合金，奥地利物理冶金和材料试验研究所同乌克兰工学院共同研究了Ｃｕ—ＡＩ—Ｍｎ新型形状记忆合金的化...     

Zn,Al对Mn—Cu减振合金减振性能的影响

研究了合金元素Ｚｎ、Ａｌ对新型减振降噪（高阻尼）铸造ＭｎＣｕ合金Ｍｓ点、减振性能及力学性能的影响,重点讨论了合金成分与减振性能ＳＤＣ及力学性能的关系。开发了高阻尼、高强度锰铜基阻尼合金ＺＭｎＤ１Ｊ,最优成分为Ｍｎ５０％、Ｚｎ５％、Ａｌ２％、余量Ｃｕ。典型性能：ＳＤＣ＝４４．５％,σｂ＝６７８ＭＰａ,δ＝２４．１％。ＭｎＣｕ系新型高阻尼功能材料的减振能力很高,同时力学性能可达ＺＧＤ３４５５７０的水平,可做结构材料使用。     

等轴应变作用下Cu,Al薄膜的取向择优生长

用分子动力学方法模拟了Cu双晶和Al双晶薄膜的（111）生长,模拟时假定在薄膜平面内保持恒定的等轴双向应变,薄膜中两晶粒的能量计算表明：不同晶粒的能量存在差异,能量较低的晶粒在沉积中择优生长,逐渐取代能量较高的晶粒,Cu膜择优生长速率显著高于Al膜：两种薄膜择优生长的机制完全不同,Cu膜中处于不利位向的晶粒通过孪晶过渡转变为择优取向,转变完成、晶界湮灭后薄膜中残留的缺陷为位错;而Al膜则是通过无序结构重结晶实现上述转变,转变完成、晶界湮灭后薄膜中残留的缺陷为间隙原子,文中对上述择优生长驱动力的来源、以及在纳米多晶中的重要性进行了讨论。     

Cu的添加对Zn-85Al钎料及Cu/Al钎焊接头性能的影响

利用不同Cu含量的Zn-85Al钎料对Cu/Al进行了火焰钎焊,采用DTA、箱式电炉、金相显微镜和万能拉伸试验机,研究了Cu对Zn-85Al钎料的熔化特性、铺展性能、显微组织、力学性能和Cu/Al接头抗拉强度的影响.试验结果表明,Zn-5Al钎料中添加1.2%(质量分数)的Cu,会稍微改善钎料在铜上的润湿性,细化钎料晶...     

Cu/Al/Cu层状金属复合材料电子束焊接接头特征

研究了Cu/Al/Cu层状金属复合材料的电子束焊,对焊接接头的表面成形、微观组织、力学性能进行分析。结果表明,采用电子束焊可以实现Cu/Al/Cu层状金属复合材料的有效连接。不同金属层焊缝宽度明显不同,铝层焊缝宽度最大,且铝层金属大量进入顶部和底部的铜层焊缝中。各层母材和焊缝界面均出现了IMCs层,铝层主要是Al2Cu,铜层则主要是AlCu,Al2Cu。在焊缝中心生成大量的块状Al2Cu,均匀分布在α-Al和Al2Cu组成的共晶组织基体中。接头抗拉强度为44 MPa,断口呈现明显的脆性断裂特征,拉伸断裂位置于显微硬度最高的焊缝中心区。 创新点： (1)采用Cu/Al/Cu层状金属复合材料代替纯铜在工业领域的应用。 (2)采用电子束焊接技术实现Cu/Al/Cu三明治结构层状金属复合材料的焊接。     

Cu／Al双金属复合材料的界面研究

选择了NH4Cl、ZnCl2、KF和K2ZrF6四种助镀剂,分别对铜进行热浸镀铝的试验,并对热浸镀后双金属结合界面的形貌、成分、金相组织以及相关机理进行研究.结果表明,选择浓度为1%～10%的KF水溶液作为助镀剂,且铝液温度为680～710 ℃,浸镀时间为2～10 s时取得了良好的助镀效果.XRD分析结果表明镀层化合物主要的相为CuAl2(θ)相.     

Abnormal grain growth in Al–3.5Cu

Significant abnormal grain growth has been observed in an Al–3.5 wt.% Cu alloy at temperatures where the volume fraction of small CuAl₂ particles was less than about 0.01. The initial fine-grained material had a weak crystallographic texture and there was no indication that any special boundaries were involved in the abnormal growth. Island grains isolated within the abnormal grains also showed no indication of special orientation relationships with their surrounding grains. Measurements indicated that the island grains initially had a size advantage over other matrix grains. The fraction of pinning phase was much lower at abnormal grain boundaries than at boundaries in the fine-grained matrix into which they were growing. A variety of simulations were made, including attempts to model that difference in pinning phase distribution, but none of these were successful in predicting abnormal grain growth.     

Comparison of the corrosion resistance of an Al–Cu alloy and an Al–Cu–Li alloy

ABSTRACT

In this study, the corrosion mechanisms of the AA2024-T3 and the AA2098-T351 were investigated and compared using various electrochemical techniques in 0.005?mol?L^?1 NaCl solution. The severe type of corrosion in the AA2098-T351 was intragranular attack (IGA) although trenching and pitting related to the constituent particles were seen. On the other hand, the AA2024-T3 exhibited severe localised corrosion associated with micrometric constituent particles, and its propagation was via grain boundaries leading to intergranular corrosion (IGC). Electrochemical techniques showed that the corrosion reaction in both alloys was controlled by diffusion. The non-uniform current distribution in both alloys showed that EIS was not a proper technique for comparing the corrosion resistance of the alloys. However, local electrochemical techniques were useful for the evaluation of the corrosion resistance of the alloys.     

Al—Pb—Cu减摩合金的热处理

本文采用正交多项式回归分析等方法,考察了Al-Pb-Cu合金在T_4、T_6和自淬火等热处理工艺中性能的变化,获得了最佳热处理工艺参数以及抗拉强度、延伸率与时效温度和时间的关系式。     

Al—Pb—Cu减摩合金的研制

本文采用正交试验等方法,设计了Al—Pb—Cu减摩合金的成分和组织,研制了一种新型铝基减摩合金。 试验结果表明,该合金可代替锡青铜制得轴瓦、轴套类滑动配件,铸件成本比ZQSn6-6-3减少4/5。     

Effects of titanium addition on structural,mechanical, tribological,and corrosion properties of Al−25Zn−3Cu and Al−25Zn−3Cu−3Si alloys

To investigate the effect of grain refinement on the material properties of recently developed Al−25Zn−3Cu based alloys, Al−25Zn−3Cu, Al−25Zn−3Cu−0.01Ti, Al−25Zn−3Cu−3Si and Al−25Zn−3Cu−3Si−0.01Ti alloys were produced by permanent mold casting method. Microstructures of the alloys were examined by SEM. Hardness and mechanical properties of the alloys were determined by Brinell method and tensile tests, respectively. Tribological characteristics of the alloys were investigated by a ball-on-disc type test machine. Corrosion properties of the alloys were examined by an electrochemical corrosion experimental setup. It was observed that microstructure of the ternary A1−25Zn−3Cu alloy consisted of α, α+η and θ (Al₂Cu) phases. It was also observed that the addition of 3 wt.% Si to A1−25Zn−3Cu alloy resulted in the formation of silicon particles in its microstructure. The addition of 0.01 wt.% Ti to the Al−25Zn−3Cu and Al−25Zn−3Cu−3Si alloys caused a decrement in grain size by approximately 20% and 39% and an increment in hardness from HRB 130 to 137 and from HRB 141 to 156, respectively. Yield strengths of these alloys increased from 278 to 297 MPa and from 320 to 336 MPa while their tensile strengths increased from 317 to 340 MPa and from 334 to 352 MPa. Wear resistance of the alloys increased, but corrosion resistance decreased with titanium addition.