Closed loop control method of laser cladding

Abstract

The invention discloses a closed loop control method of laser cladding. The closed loop control method comprises the following steps of in a laser cladding process, enabling two thermodetectors with different temperature measurement regions to be fixed to a laser, and to move along with the laser, and at the same time, aligning with the heating central positions of the laser; and measuring average temperatures Ti and Tn in two different regions as indication signals in real time, when a hole within a specific size range appears in front of movement locus of the laser, according to the changes of the indication signals, reducing the power of the laser in real time, thus overcoming the defect that the temperature of the edge of the hole is so high that the edge collapses. When the laser is away from the range of the hole, the power of the laser is readjusted, and a normal laser cladding process is restored. According to the closed loop control method disclosed by the invention, laser cladding is performed on spare parts with holes in surfaces, so that the defect that the temperature of the edge of the hole is so high that the edge collapses can be overcome, and complicated track planning is not needed. According to the method, the laser cladding process quality can be effectively improved, and the manufacturing difficulty and the manufacturing cost can be reduced.

Description

technical field [0001] The invention relates to the field of material processing and manufacturing, in particular to quality control during laser cladding on the surface of parts with cavities. Background technique [0002] Laser cladding technology is a combination of laser processing and numerical control technology. Through the method of presetting powder on the surface of the metal substrate or synchronous powder feeding, the high energy of the laser is used to melt the metal powder and form a good metallurgical bond with the substrate, thereby achieving improvement. Special processing methods for product performance. The surface hardness of laser cladding parts is high, and it has good wear resistance and corrosion resistance. Using laser cladding surface strengthening technology, high-performance alloy materials can be clad on low-cost metal parts, which can improve the working performance of products, and can also be used to repair a small amount of worn workpieces. ...

AI Technical Summary

Problems solved by technology

[0003] However, in laser cladding technology, there are still some key issues to be studied and solved, such as the problem of hole edge collapse during laser cladding

In laser cladding, if there are holes on the surface of the part, when the laser scans to the edge of the hole, it is prone to collapse, which will cause damage to the base material and affect the quality of the cladding layer

In the existing technology, the method of trajectory planning is generally adopted to avoid holes, but this will greatly increase the cost and complexity of laser cladding, and is easily limited by the specific structure and precision of the part

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