| 摘要 |
The invention relates to a process and apparatus for using laser radiation to remove an oxide layer (scale) from a hot rolled or annealed steel strip (40) by vaporization traveling in a gravitationally vertical direction at a speed of at least 10m/min. The process includes utilizing electromagnetic radiation from a high power laser such as a free electron laser whose radiation has a surface power density of at least about 5MW/cm<2> at a point of contact with the metal strip surface (44). The radiation (20) is passed through an optical system of aligned lenses or mirrors for focusing the radiation into a straight line (38) projected transversely completely across the strip. Preferably, the radiation has a pulse width less than 100 picoseconds, a pulse repetition rate greater than 10MHz and a high average power of at least 10KW. The radiation is projected completely across the width of the strip (40) to remove the oxide by vaporization by the interaction of one or more of the spatial elongated laser pulses thereby forming an oxide free surface (46). <IMAGE> |
