Electromagnetic-assisted online microstructure detection and regulation system and method

Abstract

The invention, which belongs to the field of metal additive manufacturing, specifically discloses an electromagnetic-assisted online microstructure detection and regulation system and method. The system comprises a forming device, a detection device, a regulation and control device and a base plate. The forming device, the detection device and the regulation and control device are all arranged above the base plate and the detection device is connected with the regulation and control device. The regulation and control device comprises an electromagnetic impact regulation and control unit and anelectromagnetic stirring regulation and control unit. During working, the forming device forms workpieces on the base plate layer by layer; the detection device detects the microstructure of a formedarea in real time and transmits a detection result to the regulation and control device, and then an electromagnetic impact regulation and control unit is adopted for conducting electromagnetic impact on a just-formed fused micro-area according to the detection result, or an electromagnetic stirring regulation and control unit is adopted for conducting electromagnetic stirring on a molten pool soas to regulate and control microstructures of workpieces. According to the invention, the grain size can be controlled in the forming process, defects such as air holes and incomplete fusion are reduced; and the online microstructure detection and regulation system and method have the advantages of closed loop regulation, high stability and high pertinence.

Description

technical field [0001] The invention belongs to the field of metal additive manufacturing, and more specifically relates to an electromagnetic-assisted online microstructure detection and regulation system and method. Background technique [0002] In recent years, metal additive manufacturing has been widely used in military industry, automobile, shipbuilding, mold, electronics, medical and other industries due to its advantages of high flexibility, no mold, short cycle time, and no restrictions on part structure and materials. [0003] However, in the process of metal additive manufacturing, how to effectively control the metallurgical process of melting and solidification under the conditions of rapid heat conduction, high temperature gradient and ultra-fast cooling rate of solid metal substrate "no interface thermal resistance", and then regulate the temperature of formed components Solidifying the structure, eliminating defects such as keyholes and microcracks, regulatin...

AI Technical Summary

Problems solved by technology

On the one hand, the rapid solidification of the high-temperature molten pool and the metallurgical kinetic behavior of the molten pool metal during the layer-by-layer accumulation process and its crystal nucleation and growth process directly affect the metallurgical structure of the final additively formed component (such as grain size, grain size, and grain size). Morphology, crystal orientation, grain boundary structure and uniformity of chemical composition, etc.) and mechanical properties, a single additive process can easily lead to coarse, inhomogeneous and anisotropic microstructure of the formed part, and insufficient control of the microstructure will lead to poor performance of the formed part. inadequate and unreliable

On the other hand, due to sudden cooling and sudden heating of the formed part, an excessively high temperature gradient will lead to uncontrollable deformation and large residual stress. Excessive residual stress will reduce the mechanical properties of the formed part and even lead to the generation of microcracks. Thermal cycle will lead to complex distribution of residual stress, which will lead to deformation and cracking of formed parts

These problems reduce the mechanical properties and reliability of metal additive manufacturing formed parts, thus restricting the promotion and application of metal additive manufacturing technology

[0004] At present, in the field of metal additive manufacturing research, the microstructure and performance control are mainly through the optimization of process parameters and the introduction of forced processing. , to improve the quality and performance requirements, and forced processing has a certain effect on reducing residual stress and refining grains, but it is difficult to suppress the generation of defects and is not combined with detection methods, which has the uncontrollability and blindness of tissue regulation

Images