Method and apparatus for estimating depth of molten pool during printing process, and 3D printing system

Abstract

Disclosed are a method and apparatus of estimating a depth of a molten pool formed during a 3D printing process, and a 3D printing system. A surface temperature of the molten pool is measure by taking a thermal image of a laminated printing object during the 3D printing process with a thermal imaging camera. The measured surface temperature is compared with a melting point of the base material to determine a surface boundary of the molten pool. The maximum lengths in x-axis and y-axis directions of a surface region of the molten pool defined by the surface boundary of the molten pool are determined as a length and a width of the surface of the molten pool, respectively. A maximum depth in the z-axis direction of the molten pool is determined in real time based on the length and width of the surface region of the molten pool.