Research On Uniform Deposition Of Spray Forming Billet With Two Scanning Nozzles

Spray forming with twin nozzles is used to produce simultaneously to spray large-diameter billets and to increase throughput. Therefore it is the development direction of spray forming industry in the future. In spray forming with two scanning nozzles, the distribution of the melted metal and enthalpy fluxed on the deposit surface are more complex and they have great effect on the shape of billets, depositional condition and material organization. In order to keep billet well-distributed of spray forming with twin nozzles, the conditions to obtain well-distributed billet and drive mode of scanning nozzles are studied in the paper.The existing method that can predict the shape of billet is introduced, including track coordinate, average quality and so on. Then advantages and disadvantages of them are analyzed.And the research content is put forward.The scanning deposition track of atomizing cone and its coupling conditions are studied in the paper. The mathematical models of scanning deposition trajectory coordinates and scanning deposition region are established. The effects of the eccentricity, the initial tilt angle, the largest scanning angle, the scanning frequency of the nozzle, the spray height, and the rotation speed of the substrate on scanning deposition track are analyzed and the coupling conditions are deduced in theory.Based on the theoretic models, the distribution of billet surface deposition speed is discussed when the atomizer move in different ways and a new movement manner for atomizer that can keep billet well-distributed is put forward. The cam institution that can realize the movement is designed.Parameters Optimization process of twin-atomizer spray forming is introduced, including how to choose the eccentricity, the initial tilt angle, the largest scanning angle, the scanning frequency of the nozzle, the spray height, and the rotation speed of the substrate.The theoretical models and research conclusions have been verified by spray forming experiments and the correction is showed.This method can realize parameters optimization, reduce process experiment time, reduce test costs and shorten test cycle.