ER308L焊丝硫含量对Ar-He混合气TIG焊焊缝成形的影响

采用钨极氩弧自动焊对硫含量不同的ER308L焊丝在不同Ar-He配比保护气条件下,研究了其焊缝成形规律。结果表明:随着S含量增大焊缝润湿性增加,当S≥0.01%时这种趋势更加明显;氦气比例在30%以下时,提高氦气配比焊缝熔宽增加,而对焊缝熔深影响不大。

5083铝合金中厚板变极性等离子弧立焊工艺试验

通过对16mm厚5083铝合金板变极性等离子弧立焊试验及焊后对焊缝进行各项无损检测及力学性能检测,证明变极性等离子弧焊焊接中厚铝合金板的可行性,并制定出一套成熟的焊接工艺。焊接试验结果表明,变极性等离子弧穿孔立焊中厚板铝合金,在氩氦混合气体保护下,焊前不用预热,不开坡口一次性可焊透16mm厚铝合金,焊缝成形好,接头性能优,可以实现单面焊双面成形,减少对中厚板铝合金的多层道焊,生产效率高。

Effect of Helium-Argon Mixtures on the Heat Transfer and Fluid Flow in Gas Tungsten Arc Welding

A transient finite element model has been developed to study the heat transfer and fluid flow during spot Gas Tungsten Arc Welding （GTAW） on stainless steel. Temperature field, fluid velocity and electromagnetic fields are computed inside the cathode, arc-plasma and anode using a unified MHD formulation. The developed model is then used to study the influence of different helium-argon gas mixtures on both the energy transferred to the workpiece and the time evolution of the weld pool dimensions. It is found that the addition of helium to argon increases the heat flux density on the weld axis by a factor that can reach 6.5. This induces an increase in the weld pool depth by a factor of 3. It is also found that the addition of only 10% of argon to helium decreases considerably the weld pool depth, which is due to the electrical conductivity of the mixture that increases significantly when argon is added to helium.

特高压开关铝制筒体的变极性纵缝等离子弧焊接工艺方法

常规6-12t 5052-H112铝合金板材卷制筒体的纵缝变极性等离子弧焊接工艺是不开破口单面焊双面成型,但此工艺对16t铝合金板材卷制筒体的纵缝变极性等离子弧焊接是难以保证压力容器焊缝焊接质量要求,现通过对16t 5052-H112铝合金板材卷制筒体的纵缝变极性等离子弧焊接工艺不开破口单面焊双面成型,分析工艺参数和方法对焊缝质量的影响,并制定出具体焊接工艺参数。试验结果表明,此类筒体的纵缝采用氦氩混合气作为保护气条件下不开破口单面焊双面成型焊接的方法,可以有效地避免此筒体纵缝焊接过程中受热不均导致焊缝背面局部未焊透、咬边、错边或烧穿等焊接质量问题,保证了焊接质量要求,超声波、着色、X射线探伤等检测完全合格,能够满足平高集团特高压、超高压开关筒体的设计要求。

铝锂合金飞机构件的焊接特点

介绍了用铝锂合金１４６０等制造飞机机身构件的焊接特点，焊前清理方法、气体保护。