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in the wave soldering flux principle

any metal surface in the air environment will be oxygen or other oxygen gas of different degrees of chemical etching, the surface state of metals in nature are not pure state of sheet metal. therefore,

metal welding splash proof agent use faq

strong oxidation ability aluminum easy to combine with oxygen in air to generate dense solid al2o3 thin film, the thickness of about 0.1 microns. al2o3 as high as 2050 ℃, melting point than aluminium and aluminium

at the beginning of new year to listen to the copper outlook in 2017

opper prices continue rapidly rising trend in 2017 bull market has not come; 2, 2017, after the high low before the domestic