| 摘要: |
| 负膨胀材料可以有效缓解金属的高热膨胀性，通常负膨胀材料与活性金属发生界面反应从而实现负膨胀材料与金属之间的紧密结合。但是二者之间的界面反应程度很难进行控制，过量的界面反应会破坏负膨胀材料的结构从而使其失去负膨胀特性。为此，本文通过一步水热法在负膨胀材料表面构建了一层碳阻挡层，该方法工序简单、原材料价格低廉，具有很好的应用前景。采用纯AgCuTi钎料、Sc2W3O12颗粒增强的AgCuTi复合钎料和碳层包覆的Sc2W3O12颗粒增强的AgCuTi复合钎料，在860 ℃/10 min的钎焊条件下对C/SiC复合材料和GH3536进行了真空钎焊。研究结果表明，所制备的碳阻挡层可以有效缓解负膨胀材料与活性钎料之间的界面反应，极大地降低反应层厚度，同时确保负膨胀材料与活性金属之间的紧密结合。根据接头的室温剪切强度测试结果可知，构建界面阻挡层的负膨胀材料复合钎料制备的接头剪切强度高达72 MPa，相比无阻挡层提高1.3倍，相比使用AgCuTi钎料直接钎焊提高2.5倍。 |
| 关键词: 负膨胀材料 钎焊 残余应力 |
| 基金项目:国家重点研发计划（2022******2200）；国家自然科学基金（523***02）、中国博士后科学基金（202****271；202****2831）；国家科技重大专项（J2022-******03-0045）、宁波市首批重大科技攻关项目（202***09） |
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| Regulation of Interface Reaction between Negative Expansion Material and AgCuTi Active Filler |
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Wang Pengcheng Liu Weihan Chen Haiyan* Li Wenya
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State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi’an 710072
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| Abstract: |
| Negative expansion material can effectively alleviate the high thermal expansion of metal. Usually, the interface reaction between the negative expansion material and the active metal can realize the interface bonding between the negative expansion material and metal base. However, it is difficult to control the degree of interfacial reaction between them. Excessive interfacial reaction will damage the structure of the negative expansion material and make it lose its negative expansion property. In this paper, a carbon barrier layer was constructed on the surface of negative expansion material by one-step hydrothermal method. This method has the advantages of simple and low-price, and has a good application prospect. Furthermore, pure AgCuTi filler, Sc2W3O12 reinforced AgCuTi composite filler and carbon coated Sc2W3O12 reinforced AgCuTi composite filler were used for vacuum brazing of C/SiC composite and GH3536 at 860 ℃/10 min, respectively. The results showed that the prepared carbon barrier layer can effectively alleviate the interfacial reaction between the negative expansion material and the AgCuTi filler. It not only reduces the thickness of the reaction layer, but also ensures the interface bonding. The shear strength of joints prepared by Sc2W3O12@C reinforced AgCuTi composite filler is up to 72 MPa, which is 1.3 times higher than that of Sc2W3O12 reinforced AgCuTi composite filler and 2.5 times higher than that of AgCuTi filler. |
| Key words: negative expansion material brazing residual stress |
