How to prevent the Raw Aluminum Sheet in the welding process cracks?
The Raw Aluminum Sheet in the welding process will be what causes the cracks, how can we effectively prevent the alloy 5052 aluminum welding process in the welding cracks and deformation, we have taken from the production process the following measures,
(1) the choice of electrode: the choice of a high crack resistance of the electrode, is conducive to reducing the tendency of cracks in the weld
(2) welding groove: two unequal thick plate stitching, in order to weld the weld can be a smooth transition, must be in the thick plate on the open 6 × 35 ° groove.
(3) preheating: the higher the strength level of steel, the greater the tendency to quench, the need for preheating. Proper selection of preheat and postheat systems helps to improve the microstructure and stress of the welded joints, thereby effectively improving the resistance to cold cracking. For alloy 5052 aluminum structural steel, preheating is a necessary process, for the butt joint structural parts, each side of the heating width shall not be less than 5 times the thickness of the board. In the Raw Aluminum Sheet welding, the two steel plate to be preheated, preheating area as the groove on both sides of 75 ~ 100mm range, preheating temperature of 200 ~ 350 ℃.
(4) positioning welding: In order to ensure the formation of docking joints and can penetrate, in the welding of two steel plate flat on the table, keep the gap 1mm, and welding fixture will be pressed on the platform, warm immediately after positioning Welding (spot welding), as shown in Figure 1.
(5) full welding: In order to make the weld and heat affected zone slow cooling, reduce the tendency to produce cracks, should be short-circuit welding method, that is, a long weld segment welding, so that each section of the weld Repeat for a short period of time. Alloy 5052 aluminum welding, the use of short-track jump welding method, each section of the length of 150 ~ 200mm.
The Raw Aluminum Sheet production capacity may increase the growth rate of domestic investment growth, the original demand for short-term downstream of the Raw Aluminum Sheet is difficult to change. In the context of a profound shift in China's economic growth model, it is expected that the growth rate of fixed asset investment will be further reduced in 2016, and the demand for raw aluminum will be greatly improved. But should also see the Beijing-Tianjin-Hebei coordinated development, the Yangtze River Economic Zone and other key national strategies will play a role in the Raw Aluminum Sheet to play a certain role.
2016 national primary aluminum production capacity is still possible to increase the size of the Raw Aluminum Sheet production capacity inertia increased, to resolve excess capacity long way to go. Although China's non-ferrous metal smelting and rolling industry investment fell by 6.9% in 2014, it was still at a relatively high level. There were still 2105 new aluminum plates in the Raw Aluminum Sheet industry, taking into account the inertial growth of the production capacity of the pre-construction projects. In 2016, Size is still possible to grow.
According to the monitoring data show that some of the stage of demand release, a small refill or out of the Raw Aluminum Sheet production capacity of the policy impact on the price will be short-term, we mainly focus on the cost of supporting the role of aluminum ingots, which is the main factor. We believe that the Raw Aluminum Sheet prices in 2016 will be a big shock event, driven by the Raw Aluminum Sheet prices down. The change in cost is likely to be a major factor affecting the price of the Raw Aluminum Sheet in 2016, and the analysis of the price in the steel cost analysis is particularly important. Ore supply expansion is difficult to avoid, production capacity will be more obvious in 2016. Australian aluminum ore mining industry investment started from the second half of 2012, the second half of 2013 into the peak period. From the three major Australian financial statements can be seen, 2010 - 2012 is the three major fixed assets investment growth rate is relatively high for three years, according to mine investment to reach the production cycle of about 3-4 years estimate, Australia mine in 2011 - 2012 Of the new capacity in 2015-2016 will be a clear release. 2014 will be the rapid release of aluminum production capacity and crude steel production began to reduce the year, this is our steel price is stronger than the price, the industry chain profits from the mine to the aluminum plant the main reason for the transfer. The cost of steel industry has been weakening support.