铸轧法制备铜-铝-铜复合板的界面组织与性能

采用铸轧法制备了不同厚度的铜-铝-铜复合板,并分别采用拉伸试验、剥离试验、X射线衍射仪、能谱点分析(EDS)、扫描电镜(SEM)和能谱线扫描分析(EPMA)等对复合板力学性能、形貌和组成进行了检测。检测结果表明:界面层的主要组成物为α(Al)、Cu Al2、Cu9Al4。板厚从6 mm增大到14 mm时,界面层厚度和Cu、Al原子扩散程度均逐渐增加。抗拉强度从115 MPa增大到135 MPa,延伸率从25%增加至31%,剥离强度从30 N/mm增大至35 N/mm,剥离强度即为界面层结合强度。     

铜铝复合板界面组织与性能

针对双辊铸轧工艺制备的铜铝复合板材,采用剥离试验和拉伸试验,对其力学性能进行了检测。采用扫描电镜、能谱分析仪和透射电镜等仪器对复合板界面层组织的微观形貌、结构和成分进行了分析。分析结果表明:铜铝复合板界面层的主要组成物为α-Al和Cu Al2。采用双辊铸轧工艺制备的铜铝复合板材,其剥离强度达到30 N/mm,其抗拉强度与延伸率介于同规格铜、铝板材之间。     

退火温度对铜/铝复合板剥离性能的影响

采用异步轧制方法制备铜/铝复合板,用电子万能试样机、扫描电子显微镜(SEM)及能谱仪(EDS)等分析测试手段,研究扩散退火对于铜/铝复合板结合强度、剥离裂纹位置及剥离断口化学成分的影响.研究发现,扩散退火使复合板结合强度降低,扩散层厚度随退火温度的提高而增大.复合板经350℃保温2h后,在铜/铝界面形成厚7.31μm的扩散层,经500℃保温2h后,形成厚15.53μm扩散层.退火态铜/铝复合板剥离裂纹位于靠近扩散层中间的富铝层,剥离断裂处的金属间化合物为CuAl和CuAl2.退火时形成的脆性金属间化合物以及轧制过程中形成的裂纹及未结合区是造成结合强度降低的主要原因.铜/铝轧制复合板宜采用低于350℃温度进行退火.     

基于配位聚合物薄膜的电存储器件

研究发现,2,5-二巯基-1,3,4-噻二唑(DMcT)的乙醚溶液能够与铜膜发生固-液界面反应,并在铜膜表面上形成了一层配位聚合物薄膜(Cu-DMcT).研究还发现,Cu/Cu-DMcT/Al器件具有一次写入、多次读取(WORM)的电存储性能,并有很好的成品率和信息保持性能.器件的高低阻态比可以高达106.     

原位观察铜网格增强Al/Cu复合材料的断裂行为

将一种按正交法编织的铜网格作为增强体引入到铝基体中制备了Al/Cu复合材料,再借助原位拉伸扫描电镜(SEM),观察了铝铜复合材料的组织演变,研究了其断裂机理与力学性能之间的关系.结果表明:在相同轧制变形量下,25 ℃冷轧和400 ℃热轧均可破碎增强体铜网格,并使其均匀分布于基体铝板.复合板原位拉伸下的载荷-位移曲线均表现出明显的弹性阶段、塑性阶段和失效阶段,微裂纹在Cu颗粒周围和应力集中处萌生,主裂纹及其扩展主要是Cu颗粒周围界面分层开裂与微裂纹沿滑移线方向的扩展共同作用下形成的,并且最终沿滑移线的断裂路径与单轴拉伸方向呈45°.发生在Al层的塑性断裂和Al/Cu结合界面上的界面分层断裂是Al/Cu复合板两种主要的失效方式.     

高性能铜铝复合排的制备及界面研究

采用固-液法浇注和铸轧工艺制备铝/铜复合材料.研究不同工艺对铜/铝复合排界面结合强度的影响,并对铜/铝复合排界面结构和复合机理进行分析.结果表明:当进行300°C×1h热处理时,所得复合排的结合强度最高,多次热循环后复合排界面结合强度有所增加.电子探针能谱扫描分析(EDS)和X射线衍射分析(XRD)表明铜/铝复合界面上生成金属间化合物Al2Cu,Al4Cu9和AlCu相,从而使得界面层硬度增大.采用该方法制备的铜/铝复合排,整体拉伸强度达98MPa,电阻率为0.021 6×10-6Ω.m.     

冷轧压下率对Cu/Al复合板界面和性能的影响

研究了不同冷轧压下率对铸轧法制备的Cu/Al复合板材界面微观组织和力学性能的影响。研究结果表明:冷轧过程中压下率过大时界面层会发生断裂而破碎,进而影响复合材料性能。冷轧压下率从29%逐渐增加到57%时,界面层的破碎程度逐渐加重,复合板抗拉强度逐渐增大,延伸率则随之下降,同时剥离强度先迅速减弱后缓慢增强。当冷轧压下率达到57%时,界面扩散层被严重破坏,形成大量纯铜和纯铝直接接触、无明显扩散的结合界面,铜铝复合板主要靠机械咬合力结合。     

冷轧压下率对Cu／Al复合板界面和性能的影响

研究了不同冷轧压下率对铸轧法制备的 Cu／Al复合板材界面微观组织和力学性能的影响。研究结果表明：冷轧过程中压下率过大时界面层会发生断裂而破碎,进而影响复合材料性能。冷轧压下率从29％逐渐增加到57％时,界面层的破碎程度逐渐加重,复合板抗拉强度逐渐增大,延伸率则随之下降,同时剥离强度先迅速减弱后缓慢增强。当冷轧压下率达到57％时,界面扩散层被严重破坏,形成大量纯铜和纯铝直接接触、无明显扩散的结合界面,铜铝复合板主要靠机械咬合力结合。     

TA1/Q235钢复合板累积叠轧焊界面特性

对TA1/Q235钢复合板累积叠轧焊进行了研究.研究结果表明:采用累积叠轧焊方法能够制备出结合性能较好的钛/碳钢复合板,其结合强度随着累积变形量与首道次变形量的增加而提高,叠轧过程中经磨床打磨与喷丸处理获得洁净、新鲜并具有一定加工硬化程度的结合界面,会促进复合板结合强度的提高.800℃以下热轧后,Q235钢的组织呈明显的条带状;而850℃以上热轧后,Q235钢条带状变形组织逐渐转化为等轴状,界面附近的Q235钢脱碳,出现明显的排列整齐且粗大的铁素体晶粒带.钛侧的组织主要有等轴α组织和魏氏α组织.综合考虑轧制温度对钛与Q235钢组织与界面结合性能的影响,累积叠轧温度应控制在800～850℃之间.     

铜/铝异步轧制复合带的界面反应与强化机制

采用同步和异步轧制复合工艺制备铜/铝复合带,研究退火过程中的界面反应和异步轧制工艺的强化机制.利用扫描电镜观察界面微观组织和拉伸断口形貌,通过线扫描和电子探针分析界面元素分布,采用XRD进行界面物相分析,通过剥离和拉伸实验研究复合带的力学性能.结果表明,经400℃保温1h后界面形成具有三个亚层的扩散层组织,各亚层内元素含量存在突变;铝剥离表面检测到大量铜元素,化合物相包括CuAl₂,Cu₉Al₄,CuAl和Cu₄Al,而铜剥离表面只检测到Cu₉Al₄和Cu₄Al;异步轧制工艺可以提高界面结合强度和复合带的拉伸性能,使界面层在拉伸断裂后破坏程度降低.     

Characteristic investigation of trilayered Cu/Al8011/Al1060 composite: Interface morphology,microstructure, and in-situ tensile deformation

In this work, Cu/Al8011/Al1060 trilayered composite with an ultrathin copper layer was fabricated successfully by the hybrid process of cast-rolling and hot-roll-bonding. The effects of heat treatment were investigated on the microstructure and mechanical behavior of the composite. The results showed that annealing temperatures above 300 ​°C led to the formation of new intermetallic compounds that joined their initial counterparts. Also, the interface growth was fast above 340 ​°C. It was found that the annealing temperature of 320 ​°C led to the optimal tensile properties of the composite. Through rolling, hard-brittle IMCs imposed intense plastic strains on the surrounding regions, resulting in further grain refinement of both metals in the vicinity of the interface. Although the kernel average misorientation of the trilayered composite was almost identical with the Cu/Al8011 bimetal, its amount was considerably decreased after heat treatment, as the distorted structure changed into a nearly strain-free one using the restoration phenomenon. The SEM-based in-situ tensile test showed that crack initiation occurred within the IMCs and propagated into the Cu strip, leading to its early fracture. However, the strength-displacement curve during in-situ tensile deformation did not decrease significantly due to the ultrathin copper layer.     

Effect of continuous induction annealing on the microstructure and mechanical properties of copper-clad aluminum flat bars

Copper-clad aluminum (CCA) flat bars produced by the continuous casting–rolling process were subjected to continuous induction heating annealing (CIHA), and the effects of induction heating temperature and holding time on the microstructure, interface, and mechanical properties of the flat bars were investigated. The results showed that complete recrystallization of the copper sheath occurred under CIHA at 460°C for 5 s, 480°C for 3 s, or 500°C for 1 s and that the average grain size in the copper sheath was approximately 10.0 μm. In the case of specimens subjected to CIHA at 460–500°C for longer than 1 s, complete recrystallization occurred in the aluminum core. In the case of CIHA at 460–500°C for 1–5 s, a continuous interfacial layer with a thickness of 2.5–5.5 μm formed and the thickness mainly increased with increasing annealing temperature. After CIHA, the interfacial layer consisted primarily of a Cu₉Al₄ layer and a CuAl₂ layer; the average interface shear strength of the CCA flat bars treated by CIHA at 460–500°C for 1–5 s was 45–52 MPa. After full softening annealing, the hardness values of the copper sheath and the aluminum core were HV 65 and HV 24, respectively, and the hardness along the cross section of the CCA flat bar was uniform.     

Microstructure and mechanical properties of SiC-particle-strengthening tri-metal Al/Cu/Ni composite produced by accumulative roll bonding process

In this study, a multilayer Al/Ni/Cu composite reinforced with SiC particles was produced using an accumulative roll bonding (ARB) process with different cycles. The microstructure and mechanical properties of this composite were investigated using optical and scanning microscopy and hardness and tensile testing. The results show that by increasing the applied strain, the Al/Ni/Cu multilayer composite converted from layer features to near a particle-strengthening characteristic. After the fifth ARB cycle, a composite with a uniform distribution of reinforcements (Cu, Ni, and SiC) was fabricated. The tensile strength of the composite increased from the initial sandwich structure to the first ARB cycle and then decreased from the first to the third ARB cycle. Upon reaching five ARB cycles, the tensile strength of the composite increased again. The variation in the elongation of the composite exhibited a tendency similar to that of its tensile strength. It is observed that with increasing strain, the microhardness values of the Al, Cu, and Ni layers increased, and that the dominant fracture mechanisms of Al and Cu were dimple formation and ductile fracture. In contrast, brittle fracture in specific plains was the main characteristic of Ni fractures.     

ARB工艺下Al/Zn多层复合材料界面变化的研究

累积复合轧制（Accumulative Roll-Bonding,ARB）工艺作为一种大塑性变形工艺,近期在制备金属基多层复合材料方面受到关注.通过ARB工艺制备Al/Zn多层复合材料,重点观察Al/Zn多层复合材料界面间的变化规律.在扫描电子显微镜（SEM）下,可以明显地观察到在Al/Zn界面处扩散层的存在,说明在ARB工艺状态下,不同层之间存在扩散作用,但是X射线衍射（XRD）结果无法分辨材料内部结构.通过透射电子显微镜（TEM）观察第3周期ARB态Al/Zn多层复合材料截面,可以看到,在Al/Zn多层复合材料层间,存在4种形貌的组织,参考Al-Zn合金的时效析出过程可知,在ARB工艺过程中,Al过固溶体存在连续脱溶和非连续脱溶两种路径,其脱溶路径的不同主要与扩散到Al基体中的Zn浓度有关.     

铸造1060/AZ31包铝镁合金界面结构与显微组织

为探索和改善轧制包铝镁合金板的界面结合状况,用气体保护铸造法制备了1060铝板包覆AZ31镁合金铸锭．借助金相显微镜、扫描电镜以及X射线衍射等分析方法,研究了复合铸锭芯材及界面的显微组织和相结构,并进行了硬度测试．发现AZ31镁合金芯材组织由α-Mg基体以及沿晶界分布的不连续网状α-Mg＋p＋Mg17A112共晶体组成,是一种典型的铸造离异共晶组织．铸造包铝镁合金锭界面形成扩散溶解层,扩散溶解层由α-Mg固溶体层、共晶层（α-Mg＋β＋Mg17A112）、β-Mg17A112及A1Mg化合物层组成,形成具有多层结构的冶金结合界面．提出了浇注AZ31熔体的瞬间在1060铝板表面形成“熔池”并快速凝固的界面形成机制．     

铝/铜复合界面金属间化合物

冷轧复合板轧制后要进行一定的热处理以加强界面的结合强度,但同时也带来一定的问题如在界面形成不利于界面结合的化合物,本文对冷轧制备的铝/铜层状双金属片进行了研究,得到了不同退火温度和退火时间下扩散热处理后界面金属间化合物相的生长规律,初步建立了金属间化合物形成的动力学模型.     

不锈钢／ZA43复合材料界面结构的研究

对常压浸渗法制备的不锈钢纤维增强的ZA43复合材料的界面结构进行了研究，结果表明，纤维与基体之间存在明显的界面层，此界面层由界面反应层和扩散偏聚层等多层构成，界面的形成过程主要是铁-铝金属间化合物的形成过程．同时，由于铝元素向纤维表面的偏聚和对纤维的腐蚀，导致了其它合金元素在界面处成分的不平衡分布．