Method for in-situ reducing residual stress of titanium-based composite material prepared through selective laser melting

Abstract

The invention discloses a method for in-situ reducing the residual stress of a titanium-based composite material prepared through selective laser melting. The method includes the steps that titanium-based composite material powder is prepared, wherein the titanium-based composite material powder comprises a combination of titanium or a titanium alloy and chemical substances generating reinforcingbodies, and the chemical substances comprise one or more of a B (boron) element, a C (carbon) element and rare earth elements; one or more layers of the titanium-based composite material powder is laid on a base plate of a selective laser melting device, and selective laser melting is performed; and one or more times of laser remelting is performed on the surface solidified after the selective laser melting; and operation is repeated till a titanium-based composite material component is prepared. According to the method, after laser remelting is performed on the surface solidified after selective laser melting, the local heat effect caused by scanning a powder layer by using high-energy laser beams as a heat source is lowered, the reaction of the reinforcing bodies can be more thorough, precipitation of the reinforcing bodies is thinner and smaller, the residual stress in the component preparing process is lowered, and the performance of the material is changed.

Description

technical field [0001] The invention belongs to the technical field of laser melting enhanced material manufacturing, and relates to a method for in situ reducing the residual stress of titanium-based composite materials prepared by selective laser melting. Background technique [0002] Laser additive manufacturing of titanium alloy parts will be widely used in aircraft. However, since the selective laser melting process uses a high-energy laser beam as a heat source to scan the powder layer, this local heat input causes an uneven temperature field, causing local thermal effects, making the molten pool extremely prone to residual during solidification and cooling. stress. As a result, extremely high residual stresses are present in the interior of SELM-fabricated components. The existence of residual stress will not only affect the dimensional stability of the component, but also reduce the yield strength, fatigue strength and corrosion resistance of the component, and in ...

AI Technical Summary

Problems solved by technology

[0005] The purpose of the present invention is to overcome the defects of excessive residual stress and easy cracking in the preparation of titanium-based composite materials in the prior art, and provide a method for in-situ reduction of residual stress in the preparation of titanium-based composite materials by selective laser melting