drywall black screw

The large roll of galvanized wire is violently extinguished in oxygen and sparks radiate, while the sodium block and magnesium bar are extinguished in oxygen and no sparks radiate. This phenomenon is determined by the composition of large rolls of galvanized wire. The large rolls of galvanized wire used in the experiment are pig iron or steel wire, both of which are alloys of iron and carbon (complex substances containing the elements iron and carbon). When the carbon in galvanized wire is extinguished, carbon dioxide will be produced, and the solid will be changed into a gas, and the volume will shrink rapidly.

Barbed wire welding is the reason for the occurrence of black spots is because the welding wire action to be timely in the melting time, development should be appropriate, no argon, long time burning, current, distance, tungsten needle blunt, molten pool temperature is high, is the root cause of blackening. Continuous burning, is about the active welding machine energy selection, machine welding will appear black spots.