1) chemical cleaning chemical cleaning efficiency, stable quality, suitable for cleaning up little wire and size, mass-produced artifacts. Available immersion method and scrub and French. Available acetone, gasoline, kerosene and other organic solvent surface oil, with 40 ℃ ~ 70 ℃ 5% ~ 10% NaOH solution alkaline cleaning 3min ~ 7min (pure aluminum little longer, but not more than 20min), mobile water rinse, followed by room temperature to 60 ° C, 30% HNO3 solution pickling 1min ~ 3min, mobile wash, air dry or low-temperature drying.
2) Mechanical cleaning: the large size of the workpiece, the production cycle is longer, the multilayer welding or chemical cleaning stains and then, often using mechanical cleaning. First wipe the surface with organic solvents such as acetone, gasoline degreasing, followed directly with a diameter of 0.15mm ~ 0.2mm brass wire brush or stainless steel wire brush, brush the exposed metallic luster date. Generally should not use the grinding wheel or sandpaper, sand so as not to stay on the metal surface, into the molten pool generated welding slag and other defects. Also available scraper, rasp clean up the surface to be welded.
Clean up after such long time storage (if more than 24 hours) should be re-processing.
2, the pad: aluminum alloy at high temperature strength is very low, the flow properties of the liquid aluminum, the weld metal during welding is easy to produce discover phenomenon. Welding is often used in order to ensure penetration while avoiding collapse, pad to lift up the molten pool and nearby metal. The pad may be graphite plates, stainless steel plates, carbon steel, copper, or copper rod. The surface of the pad to open a circular arc-shaped grooves, to ensure that the seam opposite molding. Also can not add the pad side welding molding proficient or advanced technology measures taken strictly for arc welding energy feedback control, but requires
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Welding Material operation.
3, preheating before welding: thin, small pieces of aluminum generally do not preheat thickness 10mm ~ 15mm can be preheated before, according to the different types of aluminum Welding Alloys preheating temperature of 100 ° C. to 200 ° C. Available oxygen acetylene flame, electric stove or blowtorch heat. Preheat the weldment can reduce distortion to reduce porosity and other defects.