A Laser Selective Melting Online Heat Treatment System

Abstract

The invention belongs to the field of forming and manufacturing of metal parts, and discloses an on-line heat treatment system for laser selective melting. The system includes a laser heat treatment unit, a laser processing unit, a temperature measurement unit, a heat treatment auxiliary unit and a control unit. The laser processing unit is used for laser selective melting and forming; The specified area is heated to make it reach the heat treatment temperature, and then the heat treatment process of the specified area of ​​the part is realized by cooperating with the heat treatment auxiliary unit; the heat treatment auxiliary unit includes a heating component and a cooling component, which are used to assist in heat treatment; It is used to monitor the temperature of the parts to be processed in real time and feed back to the control unit; the control unit is used to adjust and set the parameters of each unit. Through the invention, the residual stress of the parts is eliminated, and the parts with performance gradient distribution are rapidly prepared.

Description

technical field [0001] The invention belongs to the field of forming and manufacturing of metal parts, and more specifically relates to an online heat treatment system for laser selective melting. Background technique [0002] Selective laser melting (SLM) technology is a new rapid prototyping technology that emerged in the 1990s. It combines CAD / CAM, numerical control, optics and material science and other technologies, uses various metal powders as processing raw materials, and uses high-energy lasers to rapidly melt the powder point by point, field by field, and layer by layer according to the 3D CAD model and rapidly cool it. Direct forming metal parts with complex shapes and structures that cannot be manufactured by traditional machining methods. SLM technology breaks through the traditional ideas of deformation forming and removal forming in traditional manufacturing processes, and effectively solves the processing problems that cannot be completed by traditional proc...

AI Technical Summary

Problems solved by technology

However, the structural form of this technical scheme is too complicated. A large number of heating points and temperature measuring points not only require the structural size of the heating element and temperature measuring element to be small, but also require a more complex and precise response control system for single-point control.

In addition, the dot-matrix active temperature control system still adopts the scheme of heating from the outer wall of the forming cylinder, that is, the heat generated by the heating unit needs to pass through the entire wall thickness of the forming cylinder to be transmitted to the inside of the forming cylinder, and the temperature measured by the temperature measuring element It is also the temperature of the outer wall surface of the forming cylinder rather than the actual temperature in the forming cylinder, the response speed to the actual temperature in the cylinder is slow, and the temperature control accuracy is poor

Finally, the complex temperature control system will greatly increase the maintenance cost, and even the maintenance cost of the temperature control system will be greater than the maintenance cost of the core components of the SLM processing equipment

[0005] In addition, whether it is to perform subsequent heat treatment on the formed part or to control the temperature field of the entire processing area during the forming process to perform online heat treatment on the formed part, the existing methods are difficult to heat treat the local area of ​​the part, and cannot be based on the actual condition of the part. Use conditions and requirements to improve the local organizational structure and performance of parts, which limit the application expansion of SLM technology in aerospace, automotive, biomedical and other fields

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