【摘要】 提高和改善铝合金搅拌摩擦焊接头抗疲劳断裂性能是保证其焊接结构安全可靠的重要措施。阐述了国内外对铝合金搅拌摩擦焊接头的疲劳断裂行为的研究进展,包括铝合金搅拌摩擦焊接头的应力疲劳分析和应变疲劳分析;微结构、残余应力、表面处理对疲劳裂纹扩展速率的影响;焊接缺陷对疲劳断裂行为的影响;总结了在腐蚀介质中的疲劳裂纹形成特点和扩展规律及门槛值ΔKth。为建立铝合金搅拌摩擦焊接接头的疲劳设计规范、提高铝合金焊接结构的疲劳强度具有重要的理论意义和实践参考价值。更多还原

【Abstract】 Improving and increasing fatigue resistance of friction stir welded aluminum alloy joints is an important measure to secure the quality of welded structure.Recent researches on both domestic and foreign progresses of the fatigue fracture behavior of friction stir welded joints were reviewed in this paper.The stress fatigue analysis and strain fatigue analysis in the friction stir welded aluminum alloy joints,influences of process parameters on fatigue strength,and influences of microstructures,residual stress,surface modification and weld defects on fatigue crack growth rate were all included in these researches.Formation and growth law of the fatigue crack in corrosive environment and the threshold ΔKth were summarized.This is valuable to establish fatigue design standards for friction stir welded aluminum alloy joints and improve fatigue strength of aluminium alloy welded structures.更多还原