| Laser rapid forming (LRF) is a new and advanced manufacturing technology that has been developed on the basis of high power laser cladding technology and rapid prototyping. The rapid fabrication of high density metal components with excellent performance and complex shape can be realized without dies. Therefore, LRF is a promising manufacturing technology in high tech fields, such as aeronautic and astronautic applications. In this paper, melt pool temperature in the LRF process was measured by temperature measurement system and the influence of processing conditions on the temperature was investigated systematically. With the combination of theoretical analysis, some discussion about how to detect the forming precision and how to get unidirectional solidification microstructure was carried out. The main results are as follows:(1) Building up a temperature measurement system of the LRF processThe temperature measurement system was built up by using a two-color infrared thermometer, and the real-time tracking measurement and fixed-point measurement were achieved in the LRF process.(2) The influences of processing conditions on the melt pool thermal behaviorThe influences of powder feed rate, scanning velocity, laser power, spot diameter, shielding gas flow rate and powder feeding position on the temperature of melt pool were revealed by temperature measurement.(3) Get laser molten pool of temperature distributionThrough shooting CCD laser pool picture and combined with digital image processing of grayscale images to be distributed the image grayscale laser pool could be the temperature distribution. In order to further temperature feedback detect of laser re-manufacturing process, it provides a new solution.(4) The edition of the gray-scale processingThe software of measurement of temperature field in laser molten pool on real time based on Visual C++ and Windows XP has been developed, which consists of data of temperature field analyzing. |
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