2219 aluminum alloy parts need helium arc priming before welding. Due to the helium arc bottoming welding, the molten pool is stable, and after cooling, a straight weld is formed, and the bottom is flat and bright. During the helium arc bottoming process of the 2219 aluminum alloy forging part (referred to as "2219 aluminum forgings"), the molten pool is boiling, and the bottom is matt color after cooling, and there is no flat bright band formed, which is a fault phenomenon.
Abnormal welding state The Bi content of 2219 aluminum alloy forging part exceeds the required value (<0.05%) of the GB/T3190-2008 standard, resulting in abnormal surface morphology of the weld after cooling. After quality review, there were operational errors in the production process, and the introduction of Bi-containing alloys in the batching process was the cause of the excessive Bi content in this forging.
In order to ensure that such failures do not occur again, the following rectification measures are proposed:
1) For welding raw materials, put forward the acceptance index requirements of low melting point metal elements such as Bi and Sn;
2) During the smelting process of raw materials, the main elements of the alloy smelted in the previous furnace should be used as the impurity elements in the furnace for the analysis and monitoring before the furnace for detection and analysis;
3) Strengthen the management and control of the storage, transportation and use of alloys and pure metals, and improve the detection range and detection capabilities of chemical components in the smelting process