Welding difficulty (1) easily oxidized. In the air, the aluminum oxide combined with easy starter recovery, generating a dense aluminum oxide film (thickness of about 0.1-0.2μm), high melting point (about 2050 ℃), far more than aluminum and aluminum alloys melting point (about 600 ℃). Alumina density 3.95-4.10g / cm3, aluminum is approximately 1.4 times the surface of the aluminum oxide film of easy absorption of moisture, welding, it prevents fusion of the base metal, easy to form pores, slag, No fusion defects, performance degradation caused by welding. (2) easy to produce pores. The main reason porosity of aluminum and aluminum welding is hydrogen, since large amounts of hydrogen soluble liquid aluminum, and solid aluminum hardly dissolved hydrogen, so that when the bath temperature rapid cooling and solidification, Liaocheng starter recovery, hydrogen late Yi out, easy to gather the formation of pores in the weld. Hydrogen is difficult to completely avoid the holes, many sources of hydrogen, electric arc atmosphere of hydrogen, aluminum, wire surface oxide film adsorbed moisture in the air and so on. Practice has proved that, even if the argon gas by GB / T4842 standards, purity of 99.99%, Linyi starter recovery, but the moisture content reaches 20ppm, there will be a lot of dense pores, when the relative humidity exceeds 80% Heze starter recovery, if measures are not taken heat, weld porosity will obviously appear. At the same time, using a small welding current slow increase weld cooling time, and use wire arcs puddle agitation, can better help the gas discharge bath. Secondary wrought aluminum alloy: 2000 series aluminum representatives 2024,2A16 (LY16), 2A02 (LY6). 2000 series aluminum is characterized by high hardness, which the copper content, probably in about 3-5%. 2000 series aluminum rod is aviation aluminum in conventional industrial infrequent application. Three Lines: 3000 series aluminum alloy on behalf of 3003, 3A21 based. Our 3000 series aluminum production process is relatively good. 3000 series aluminum rod is composed of manganese as a main ingredient. Content is between 1.0-1.5, is a rust-proof function better. Aircraft four lines: 4000 series aluminum bar representatives 4A01 4000 series aluminum is higher silicon content. Usually silicon content of 4.5-6.0%. Are used in construction materials, machinery parts, forging materials, welding materials; low melting point, good corrosion resistance, the product description: with heat and wear characteristics of Linyi recycling starter, starter recycling, scrap metal recycling Shengxin by the Linyi City Sheng Xin scrap metal recycling Limited. Linyi City Shengxin scrap metal recycling Ltd. (shengxin.tz1288.com) strong, credible, in Linyi, Shandong scrap metal industry has accumulated a large number of loyal customers. The company better work attitude and constantly improving innovative ideas will lead Shengxin scrap metal recycling into the brilliant and you work for a better future!