Support-free 3D printing method

Abstract

The invention discloses a support-free 3D printing method, which is characterized in that a currently printed part layer is set as an Nth layer, a next layer to be printed is set as an (N + 1) th layer, in a small-angle area, a part of area of the (N + 1) th layer can exceed a boundary line of the Nth layer, the part of area exceeding the boundary is defined as a suspended area, the suspended width of the suspended area is defined as W, and defining an included angle between a connecting line from the (N + 1) th layer of bottom edge to the Nth layer of bottom edge and the horizontal direction as alpha. The ratio of the laser power P to the laser scanning speed V is adjusted in time in the laser scanning process of the inner side and the outer side of the boundary and the suspension area, when the laser beam scans the (N + 1) th layer of overlapping area, the spot diameter phi of the laser beam is controlled to be kept unchanged or amplified, and after the laser beam scans the (N + 1) th layer of small-angle suspension area and the overlapping area, the laser beam is controlled to be not changed. And the spot diameter phi of the laser beam is controlled to be reduced, and based on the principle, the suspended area and the overlapped area of each part layer can be printed and formed under the condition of not depending on a supporting body.

Description

technical field [0001] The invention relates to a 3D printing method, in particular to an unsupported 3D printing method. Background technique [0002] In the existing technology, laser selective melting forming technology is a commonly used 3D printing process. Because of the technical principle of layer stacking, it is often necessary to add block support to the small angle area of ​​the part to form it. For semi-closed structures, small For workpieces with gaps in size, there may be situations where supports cannot be added or there is not enough space to use tools to remove them after adding supports. At the same time, the way of adding supports will lead to increased powder consumption, longer forming time, and low manufacturing efficiency. Contents of the invention [0003] The technical problem to be solved by the present invention is to provide an unsupported 3D printing method that does not need to add a large number of supports, saves powder, has short forming ti...

AI Technical Summary

Problems solved by technology

[0002] In the existing technology, laser selective melting forming technology is a commonly used 3D printing process. Because of the technical principle of layer stacking, it is often necessary to add block support to the small angle area of ​​the part to form it. For semi-closed structures, small For workpieces with gaps in size, there may be cases where supports cannot be added or there is not enough space to use tools to remove them after adding supports. At the same time, the way of adding supports will lead to increased powder consumption, longer forming time, and low manufacturing efficiency.

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