交流频率及装配质量对单面自动焊接头性能的影响分析
厉晓笑
杜岩峰
郝云飞
田堂振
（首都航天机械公司，北京100076）
王道虎
文摘开展了6mm2A14-T6铝合金对接接头的单面焊双面成形焊接工艺研究，详细分析了交流频率和装配精度对焊缝成形及接头力学性能的影响规律。结果表明：随着交流频率从60Hz逐渐增加至80Hz， 2A14铝合金对接接头的平均抗拉强度从356MPa降低至310MPa，但接头延伸率没有显著变化。装配精度对焊缝质量的影响分析结果显示：随着装配间隙增大，焊缝背部成形效果变差。当间陳超过20%板厚时，焊缝易直接熔穿或单面切割，无法形成焊漏。随着装配错边增大，焊缝背部成形逐渐变差，出现咬边现象；接头力学性能测试显示，随着装配错边的增加，接头抗拉强度和延伸率均呈逐渐下降的趋势。在实际工程应用中，局部错边应控制在25%板厚范图内。
关键词单面焊双面成形，交流频率，装配精度，接头性能
中图分类号：TC4
D0I:10.3969/j.issn.10072330.2015.04.023
EffectofAlternatingCurrentFrequencyandAssemblyQualityon
Properties of One-Side Automatic Welding Joint
LIXiaoxiao
HAOYunfei
TIANTangzhen
DUYanfeng
(Capital Aerospace Machinery Company, Beijing 100076)
WangDaohu
AbstractThis paper investigated the welding process of one-side welding with backing formation of 6 mm 2A14-T6 aluminum alloy, and analyzed the discipline of the alternating current frequency and assembly accuracy to the welding formation and the joint performance. The results showed that with the AC frequency gradually increased from 60 Hz to 80 Hz, the average tensile strength decreased from 356 MPa to 310 MPa, but the joint elongation did not change significantly. The analysis of assembly accuracy showed that the body material would be burnt through or sin-gle cutting by one-side when the assembly clearance exceeded 20% of thickness which was unable to form welding leakage. On the other way, when the larger assembly stagger was come out, the mechanical properties of joint de-creased obviously. In addition, the influence of stagger on the performance was greater than the clearance. When the stagger was increased, the backing formation would be worse.The result of joint performance showed that if the stag ger was greater, the joint tensile strength and elongation declined gradually. So in practical engineering applications, the local stagger of joints should be controlled within 25% of thickness.
Key wordsOne-side welding both sides formation, Altemating Current frequency, Assembly accuracy, Per-formance of welding joint
0引言
航天2A14铝合金焊接性较差，易产生焊接裂纹。为提高接头力学性能，我国现役系列运载火箭贮箱广泛采用“内侧双层自动焊接+外侧手工封底”的两面三层焊接工艺，旨在通过手工封底工艺增加焊缝热输入以提高接头的延伸率。但是两面三层焊工艺
收稿日期：2014-1202
方法易导致贮箱焊缝产生气孔、夹渣和未熔合缺陷，且生产效率较低。为此逐步开展以“直流氮弧打底+ 交流脉冲氢弧盖面的单面焊双面成形工艺的研究。实际工程应用中影响单面焊双面成形焊接接头性能的因素较多]，文中直流氮弧打底焊接工艺的所有参数及盖面焊接工艺的电源、焊接速度等参数均固定
作者简介：厉晓笑，1987年出生，颈士，工程师，主要从事忙箱焊接及型号管理工作。E-mail：lixiaoxiao0809@163.com
宇航材料工艺万方数据
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2015年第4期
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