张红娟

摘要：本文对6061-T651铝合金薄壁箱体真空钎焊时采用的夹具和装夹方式进行了研究。通过对箱体结构、装夹方式、焊接过程及焊接缺陷进行分析，发现钎焊夹具及装夹方式是产生焊接缺陷的主要原因，进而对钎焊夹具及装夹方式进行研究和改进。根据箱体结构特征重新设计加工U型夹和夹板，真空钎焊时采用整体装夹和局部夹紧的双装夹方式使箱体真空钎焊一次合格率由10%提升到90%，验证了合理改进钎焊夹具可以明显提升焊接质量。

关键词：铝合金;真空钎焊;钎焊夹具

Abstract： In this paper，the fixture and clamping method used in vacuum brazing of 6061-T651 aluminum alloy thin wall box are studied. Through the analysis of box structure， clampingmethod，welding process and welding defects，it is found that brazing fixture and clamping mode are the main reasons for welding defects，and then the brazing fixture and clamping mode are studied and improve. According to the structural characteristics of the box， the U-clamp and splint were redesigned and processed. During vacuum brazing， the double clamping mode of integral clamping and local clamping was adopted.The first pass rate of vacuum brazing was increased form 10% to 90%. It is verified that the reasonable improvement of brazing fixture can significantly improve the welding quality.

Key words： aluminum alloy;vacuum brazing;brazing fixture

0  引言

铝合金密度小、导电、导热性能好，在机载电子设备中得到广泛应用。随着时代的发展，对机载电子设备重量提出了更高的要求，为此机载电子设备中的铝合金箱体向薄壁化、轻便型发展。薄壁铝合金箱体自身强度不足，热胀冷缩后箱体变形量大，为提升焊接质量，根据前期经验分析，需要对焊接夹具和装夹方式进行改进。本文通过对某薄壁铝合金箱体结构及该箱体采用现有焊接夹具和装夹方式进行真空钎焊产生的缺陷进行分析研究，对焊接夹具和装夹方式进行改进，使薄壁铝合金箱体真空钎焊焊接质量得到明显提升。

1  薄壁铝合金箱体结构分析

某机载电子设备对机箱强度和轻便型要求高，为满足强度和重量要求，组成箱体的各零件选用6061-T651铝合金进行加工，零件结构多选用凹池和加强筋组合的特征以最大限度减轻箱体重量，零件加工完通过真空钎焊的方式组成箱体。……