| 摘要: |
| 铝合金及其电阻点焊工艺的应用日益广泛,对其性能和质量也提出了更高的要求.鉴于点焊熔核的宏观性能由其微观结构决定,通过改变熔核的微观组织结构来强化熔核质量,从而提高焊点性能.选用碳纳米管作为铝合金点焊熔核的添加介质,对点焊试验结果进行力学性能测试、显微组织结构观察和成分分析.结果表明,在铝合金熔核中添加碳纳米管后,熔核的晶粒尺寸明显减小,碳纳米管均匀分布在熔核中,能显著提高熔核的硬度和强度.经过进一步分析认为碳纳米管的强化机制主要为位错增殖、载荷传递、约束变形以及细晶强化. |
| 关键词: 铝合金 电阻点焊 碳纳米管(CNT) 强化理论模型 |
| DOI： |
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| 基金项目:国家自然科学基金资助项目(50975197);天津应用基础研究计划基金资助项目(09JCZDJC24000);国家科技支撑计划项目(2011BAF11B08) |
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| Study on influence of CNT to nugget of aluminum alloy spot welding |
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WANG Hao1,2, LUO Zhen1,2, ZHOU Linshu1, ZHANG Di1,2
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1.School of Materials Science and Engineering, Tianjin University, Tianjin 300072, China;2.Tianjin Key Laboratory of Advanced Joining Technology, Tianjin University, Tianjin 300072, China
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| Abstract: |
| The process of aluminium alloy spot welding is widely used nowadays and the industry puts forward higher request in its properties and quality.The microstructure of aluminium alloy spot welding nuggets decides its macroscopic properties.In this paper,the microstructure of nugget was changed to enhance its properties and quality.Carbon nano-tube(CNT) was chosen as the addition of the aluminium alloy spot welding,and further analysis of the mechanical properties,microstructure and components of the welding spot of aluminium alloy.The results indicated that when the CNT was added in the aluminium alloy,the sizes of spot welding grain decreased significantly.The CNT distributed uniformly in the nuggets and it could increase the hardness and intensity significantly.The further analysis indicated that the carbon nano-tubes strengthening mechanism was mainly dislocation multiplication,transformation of load,constrained deformation and fine grain strengthening. |
| Key words: aluminum alloy resistance spot welding carbon nano-tube model of strengthen theory |
