Method and equipment for manufacturing three-dimensional object

Abstract

The invention describes a method for achieving manufacturing of a three-dimensional object by conducting layer-by-layer scanning on a powder layer through an energy bundle. The method comprises the steps that a powder material layer is paved on a base plate or a cured layer, so that the powder layer is formed; part of or more areas of the powder layer are preheated through a preheating light beam, so that the temperature of powder in the preheated areas reaches a set value, wherein setting of the preheating light beam is matched with absorption efficiency of the powder; selective scanning is conducted on the corresponding cross section positions, in the preheated areas, of the three-dimensional object through the energy bundle, and curing of the powder layer is completed, wherein the preheating light beam is a laser beam with the single wave length; and after homogenization is conducted and the light beam uniform in energy distribution is formed and diverged, preheating is conducted on the preheated areas. By means of the method, a powder material adopted in the powder bed additive manufacturing technology can be preheated rapidly and efficiently, and thus the temperature difference generated between the three-dimensional object and the surrounding environment when the three-dimensional object is manufactured is reduced; generation of internal stress is reduced; and manufacturing quality of the three-dimensional object is improved.

Description

technical field [0001] The invention relates to a method and related equipment for manufacturing a three-dimensional object layer by layer through the action of energy beams on powder. Background technique [0002] Common additive manufacturing methods include using energy beams (such as lasers or electron beams) to selectively scan the pavement layer of powder materials, and finally obtain a three-dimensional object through layer-by-layer scanning and solidification accumulation. The scanning position of the energy beam is the corresponding cross-sectional part of the layer of the three-dimensional object to be manufactured. The temperature of the powder material corresponding to this part rises rapidly after the action of the energy beam, and the material is melted instantly and solidified after cooling. After one layer of scanning is completed, continue to spread a new layer of powder on the completed scanning layer, and scan the corresponding cross-section of the new pow...

AI Technical Summary

Problems solved by technology

However, the problem is that the infrared radiation heater has a wide range of radiation wavelengths, and the powder has different absorption rates for different wavelengths of radiation, which affects the temperature balance of the powder surface, and the time for the powder material to absorb infrared radiation to the set temperature is longer, which is more due to heating. Due to the low directivity of the device radiation, the working cavity will also heat up due to radiation, thus putting forward higher temperature tolerance requirements for the cavity and the components in the cavity

In the prior art, a heater is installed under the substrate of the laser sintering equipment for manufacturing metal three-dimensional objects to preheat the substrate, and the three-dimensional object is kept warm through the heat conduction of the substrate, but the substrate has a large thermal resistance, low heat transfer efficiency and time-consuming heating longer

Images