METHOD OF CONTROLLING THE COOLING RATE OF A MELT POOL OF A POWDER BED, AND DIRECT METAL LASER MELTING MANUFACTURING SYSTEM WITH IN-LINE LASER SCANNER

摘要

A method of controlling the cooling rate of a melt pool of a powder bed includes directing a first laser beam on the powder bed to form a melt pool; coaxially aligning a second laser beam with the first laser beam; and laterally offsetting a focus spot of the second laser beam with respect to the melt pool, wherein the second laser beam heats but does not melt powder within the focus spot.