Al-Cu体系梯度复合材料的流延法制备及其结构控制
发布时间：2018-12-20 15:24
【摘要】：梯度复合材料是一类组成、结构及性能沿着厚度方向渐变的非均质复合材料。梯度复合材料能够同时具备均质材料所不能拥有的两种相矛盾的特性,被广泛应用在航空航天、电磁、核工程和光电工程等领域中。本文针对以往Al-Cu梯度复合材料制备过程中结构难以精确控制、致密化困难等问题,采用流延成型法和真空热压烧结法实现梯度复合材料的致密化与梯度结构的精确控制。本文首先采用0.6wt.%Hypermer KD-1作为分散剂,2.7wt.%聚乙烯醇缩丁醛(PVB)作为粘接剂,3wt.%甘油作为增塑剂,33.7wt.%无水乙醇和丁酮作为溶剂,调整Al和Cu粉配比,在流延机第一刀高度为200μm,第二刀高度为80μm,基带速率为2.5mm/s的条件下制备出了不同组分Al-Cu的流延膜片。流延膜片均匀性好、无明显分层沉降,流延膜厚度分布近似于正态分布,厚度范围为40-61μm。以排胶后的Al、Cu混合粉体为原料,在真空热压条件下制备出了从纯铝到纯铜组分的Al-Cu复合材料,并对制备出的Al-Cu复合材料的结构进行了系统分析。研究结果表明,在500oC-300MPa-2h的烧结工艺条件下实现了Al-Cu复合材料的致密化,其致密度达到95.63%以上。Al-Cu复合材料中,主要的物质是Al和Cu元素,但是还含有少量的碳元素,碳元素的质量分数为0.08%-0.84%。碳元素主要是以有机物和碳单质的形式存在于复合材料中的。Al/Cu颗粒间主要生成厚度约为2-3.5μm扩散层,并未发现金属间化合物生成。采用了直接混料法得到的Al-Cu复合材料作对比,系统分析了烧结后残炭对Al-Cu复合材料结构和性能的影响。研究结果表明:残碳对Al-Cu复合材料的物相、显微结构及硬度值没有明显的影响。然而残碳降低了Al-Cu复合材料的密度值,从而降低了Al-Cu复合材料的致密度,导致开气孔率几乎为零的纯铜其致密度仅为95.63%。同时,残碳降低了Al-Cu复合材料的声波阻抗值,其中纯铜的降低幅度最大,达到19.56%。流延法制备的Al-Cu复合材料的抗弯强度显著减小,且随着铜含量的增加而逐渐增加,其中纯铝的抗弯强度值最小为47.9MPa,纯铜的抗弯强度最大为227.11MPa。最后,本文根据设计的组成-厚度曲线,采用以上确定的排胶工艺和真空热压烧结工艺,制备出了铜含量为0-66.03wt.%的8层Al-Cu梯度复合材料。梯度复合材料的组分控制精度为0.19%-2.9%,厚度控制精度为0.3%-9.6%,厚度误差范围不超过±0.01mm。梯度复合材料整体致密,Al、Cu颗粒分散均匀,层间结合良好,无明显的孔洞及裂纹存在。此外,Al-Cu梯度复合材料的平面度好,Al面平面度值约为6.06μm,高铜面平面度值为7.64μm。超声无损检测显示Al-Cu梯度材料内部无明显缺陷,层间平行性良好。
[Abstract]:Gradient composite is a kind of heterogeneous composite material whose structure and properties change gradually along the thickness direction. Gradient composites are widely used in aerospace, electromagnetism, nuclear engineering and optoelectronic engineering, because they can not possess two kinds of contradictory properties that homogeneous materials can not possess at the same time. In order to solve the problems of difficult structure control and densification in the preparation of Al-Cu gradient composites in the past, the method of casting forming and vacuum hot pressing sintering was used to realize the densification of gradient composites and the precise control of gradient structures. Firstly, 0.6wt.%Hypermer KD-1 was used as dispersant, (PVB) was used as adhesive, 3wt.% glycerol as plasticizer, 33.7 wt.% anhydrous ethanol and butanone as solvent. When the ratio of Al and Cu powder is adjusted, under the conditions of the first knife height of the casting machine is 200 渭 m, the second knife height is 80 渭 m and the base band rate is 2.5mm/s, the different component Al-Cu thin films have been prepared. The thickness distribution of the film is similar to normal distribution, and the thickness range is 40-61 渭 m. The Al-Cu composites from pure aluminum to pure copper were prepared under vacuum hot pressing using the mixed powder of Al,Cu after rubber removal. The structure of the prepared Al-Cu composite was systematically analyzed. The results show that the densification of Al-Cu composites is realized under the sintering conditions of 500oC-300MPa-2h, and the densification of Al-Cu composites is more than 95.63%. The main materials in Al-Cu composites are Al and Cu elements. But it also contains a small amount of carbon, with a mass fraction of 0.08-0.84. The carbon elements are mainly in the form of organic compounds and carbon elements in the composites. The interparticle thickness of Al/Cu is about 2-3.5 渭 m, but no intermetallic compounds are found. The effects of sinter carbon on the structure and properties of Al-Cu composites were systematically analyzed. The results show that the residual carbon has no obvious effect on the phase, microstructure and hardness of Al-Cu composites. However, carbon residue decreases the density of Al-Cu composites, thus reducing the density of Al-Cu composites, resulting in pure copper with almost zero porosity. The density of pure copper is 95.63. At the same time, carbon residue decreases the acoustic impedance of Al-Cu composites, and the pure copper decreases by 19.56. The bending strength of Al-Cu composites prepared by casting method decreased significantly and increased gradually with the increase of copper content. The minimum flexural strength of pure aluminum was 47.9 MPA, and the maximum bending strength of pure copper was 227.11 MPA. Finally, according to the compound-thickness curve of the design, 8-layer Al-Cu gradient composites with copper content of 0-66.03wt.% were prepared by using the above determined gelling process and vacuum hot pressing sintering process. The component control accuracy of the gradient composite is 0.19- 2.9, the thickness control accuracy is 0.3-9.6, and the thickness error range is not more than 卤0.01mm. Gradient composites are compact, Al,Cu particles are uniformly dispersed, interlaminar bonding is good, and there are no obvious pores and cracks. In addition, the planeness of Al-Cu gradient composite is good, the planeness of Al surface is about 6.06 渭 m, and that of high copper surface is 7.64 渭 m. Ultrasonic nondestructive testing showed that there was no obvious defect in Al-Cu gradient material and the parallelism between layers was good.
【学位授予单位】：武汉理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TB33
本文编号：2388182
[Abstract]:Gradient composite is a kind of heterogeneous composite material whose structure and properties change gradually along the thickness direction. Gradient composites are widely used in aerospace, electromagnetism, nuclear engineering and optoelectronic engineering, because they can not possess two kinds of contradictory properties that homogeneous materials can not possess at the same time. In order to solve the problems of difficult structure control and densification in the preparation of Al-Cu gradient composites in the past, the method of casting forming and vacuum hot pressing sintering was used to realize the densification of gradient composites and the precise control of gradient structures. Firstly, 0.6wt.%Hypermer KD-1 was used as dispersant, (PVB) was used as adhesive, 3wt.% glycerol as plasticizer, 33.7 wt.% anhydrous ethanol and butanone as solvent. When the ratio of Al and Cu powder is adjusted, under the conditions of the first knife height of the casting machine is 200 渭 m, the second knife height is 80 渭 m and the base band rate is 2.5mm/s, the different component Al-Cu thin films have been prepared. The thickness distribution of the film is similar to normal distribution, and the thickness range is 40-61 渭 m. The Al-Cu composites from pure aluminum to pure copper were prepared under vacuum hot pressing using the mixed powder of Al,Cu after rubber removal. The structure of the prepared Al-Cu composite was systematically analyzed. The results show that the densification of Al-Cu composites is realized under the sintering conditions of 500oC-300MPa-2h, and the densification of Al-Cu composites is more than 95.63%. The main materials in Al-Cu composites are Al and Cu elements. But it also contains a small amount of carbon, with a mass fraction of 0.08-0.84. The carbon elements are mainly in the form of organic compounds and carbon elements in the composites. The interparticle thickness of Al/Cu is about 2-3.5 渭 m, but no intermetallic compounds are found. The effects of sinter carbon on the structure and properties of Al-Cu composites were systematically analyzed. The results show that the residual carbon has no obvious effect on the phase, microstructure and hardness of Al-Cu composites. However, carbon residue decreases the density of Al-Cu composites, thus reducing the density of Al-Cu composites, resulting in pure copper with almost zero porosity. The density of pure copper is 95.63. At the same time, carbon residue decreases the acoustic impedance of Al-Cu composites, and the pure copper decreases by 19.56. The bending strength of Al-Cu composites prepared by casting method decreased significantly and increased gradually with the increase of copper content. The minimum flexural strength of pure aluminum was 47.9 MPA, and the maximum bending strength of pure copper was 227.11 MPA. Finally, according to the compound-thickness curve of the design, 8-layer Al-Cu gradient composites with copper content of 0-66.03wt.% were prepared by using the above determined gelling process and vacuum hot pressing sintering process. The component control accuracy of the gradient composite is 0.19- 2.9, the thickness control accuracy is 0.3-9.6, and the thickness error range is not more than 卤0.01mm. Gradient composites are compact, Al,Cu particles are uniformly dispersed, interlaminar bonding is good, and there are no obvious pores and cracks. In addition, the planeness of Al-Cu gradient composite is good, the planeness of Al surface is about 6.06 渭 m, and that of high copper surface is 7.64 渭 m. Ultrasonic nondestructive testing showed that there was no obvious defect in Al-Cu gradient material and the parallelism between layers was good.
【学位授予单位】：武汉理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TB33
【参考文献】
相关期刊论文 前10条
1 李君;罗国强;沈强;张联盟;祝洪喜;邓承继;;Mg-Cu密度梯度材料的流延法制备[J];复合材料学报;2012年02期
2 李君;罗国强;沈强;张联盟;;流延法制备梯度功能材料的研究进展[J];中国材料进展;2009年04期
3 ;Effect of Ce on the thermal stability of the Ω phase in an Al-Cu-Mg-Ag alloy[J];Rare Metals;2009年02期
4 刘延斌;刘志义;李云涛;夏卿坤;周杰;段水亮;;时效温度对Al-5.06%Cu-0.44%Mg-0.55%Ag-0.3%Mn-0.17%Zr合金组织与性能的影响[J];中南大学学报(自然科学版);2008年03期
5 庞建超,高福宝,曹晓明;功能梯度材料的发展与制备方法的研究[J];金属制品;2005年04期
6 韩杰才,徐丽,王保林,张幸红;梯度功能材料的研究进展及展望[J];固体火箭技术;2004年03期
7 李亚江,吴会强,陈茂爱,杨敏,冯涛;Cu/Al真空扩散焊接头显微组织分析[J];中国有色金属学报;2001年03期
8 张幸红,韩杰才,董世运,杜善义;梯度功能材料制备技术及其发展趋势[J];宇航材料工艺;1999年02期
9 李德成,刘玉贤,丁建国,单海波,高海峰,夏志敏,荣福杰;高强铸造铝合金A-U5GT及其应用[J];铸造;1998年11期
10 李克平,张同俊;新型梯度功能材料的研究现状与展望[J];材料导报;1996年03期
相关博士学位论文 前1条
1 刘树龙;W-Cu体系功能梯度复合材料的水基流延法制备及其性能研究[D];武汉理工大学;2013年
相关硕士学位论文 前2条
1 张相龙;C_f/Al复合材料与TiAl自蔓延连接工艺及机理研究[D];哈尔滨工业大学;2012年
2 丛茜;成分连续Al/Al-Cu梯度材料的制备及力学性能[D];大连理工大学;2011年
，本文编号：2388182
本文链接：https://www.wllwen.com/kejilunwen/cailiaohuaxuelunwen/2388182.html
