Productive coating process for a steel sheet and corresponding equipment

A method for manufacturing a coated steel sheet comprising the following steps:

• a. providing a steel sheet;
• b. descaling the steel sheet by acid pickling;
• c. feeding the descaled steel sheet into a pressurized chamber above the atmospheric pressure, the pressurized chamber including an inlet, and being connected via at least one sealing lock to at least one vacuum deposition chamber;
• and
• d. depositing a metallic coating layer by vapor deposition at a sonic speed,
• wherein a gas is blown into the pressurized chamber to keep the pressurized chamber at a pressure above atmospheric pressure, the gas being released through the inlet.

Equipment for the manufacturing of a coated steel sheet comprising the following units through which the steel sheet is successively driven:

• a pickling unit allowing the removal of scale on the surface of the steel;
• a pressurized chamber having an inlet and being connected to a sealing lock;
• at least one jet vacuum deposition chamber;
• and
• a blower for blowing a gas into the chamber to keep the chamber above atmospheric pressure, the gas being released outside the pressurized chamber through the inlet.

A metallic coated hot rolled steel sheet, comprising successively:

• a hot rolled steel sheet;
• an oxide layer in contact with the sheet having a thickness from 3 to 60 nm and being mainly composed of iron oxides;
• and
• a metallic coating having a thickness from 2.0 to 75.0 μm per side.