On-line detection method for laser cladding process by directly calibrating and detecting temperature field melting bath width with test sample

Abstract

The invention particularly relates to a real-time on-line detection method for a laser cladding process. The traditional on-line detection method needs a special metering mechanism to calibrate the instrument, which increases the expenses and is very inconvenient. The invention provides an on-line detection method for a laser cladding process by directly performing calibration by comparing a test sample with information acquired in a testing process. In the test calibration process, people only determine the proportional relation between the actual melting bath region of the test sample and the corresponding region in the detected information, and does not determine the definite melting temperature of the workpiece material. In the detection process, the system acquires information on the range of the workpiece surface in the molten state, and the accurate temperature value and distribution thereof are not required. The invention can be used for avoiding some calibration work performed by the professional metering mechanism, detection errors caused by temperature calibration errors, and misjudgment caused by variations of actual melting temperature and the like due to variations of materials or technological conditions.

Description

Technical field [0001] The invention relates to an online detection method, in particular to a method for real-time online detection of a laser cladding process. Background technique [0002] The laser cladding process can not only modify the surface, improve the surface performance and service life of the workpiece, but also repair precious metal parts and directly manufacture special metal parts that are not easy to form by traditional methods. Because laser cladding is a very complicated process, slight fluctuations of certain factors will cause changes in the laser cladding bath and lead to unstable quality; in addition, for workpieces with more complex structures, the heat conduction conditions of different parts Different, the molten pool formed by laser cladding is also different, and so on. These problems affect the quality of the workpiece. [0003] The measures to solve these problems are real-time online control of the laser cladding process. At present, people's gene...

AI Technical Summary

Problems solved by technology

However, due to the different materials of the workpiece (substrate, cladding powder), the melting temperature is also different, and the radiation signal is also different at the same temperature; the heating and cooling conditions are different, and the melting superheat and solidification supercooling are different; In addition, the sensor The conditions of workpiece detection are different, and the strength of the signal received by the sensor also changes.

Therefore, before testing the laser cladding process of each workpiece under different process conditions, it is necessary to go to a special measuring institution to calibrate the instrument, which requires a lot of manpower, material and financial resources, and is very inconvenient and greatly restricts The popularization and application of laser cladding technology