Spray deposition for making large size billet with swing atomizer

Abstract

The movement mode of the atomizer is a very important parameter during spray deposition process, which has direct influence on the size and surface texture of the billets. To resolve the problem of manufacturing large size billets, a method of spray deposition by the atomizer with off-center swing was put forward. The atomizer was driven by the alternating current servomotor to swing within 7Û at varying speed. The influence of the atomizer parameters, such as translation of the atomizer, swing angle of the atomizer, substrate falling speed and spraying pressure, on the spray deposition was studied. The optimized parameters of the spray deposition process were obtained. The results show that the large size billets with uniform surface quality can be made through adjusting swing frequency and angle of the atomizer, offset distance of the atomizer and inclined angle of the substrate; the valid spray area will decrease and the dimension of top surface will reduce when pressure is less than 0.4 MPa within certain spray distance; meantime, the moving time and cooling time of the droplets are extended, which will lead to loose structure and bad densification. When the pressure, the swing angle and the eccentric offset of the atomization equal 0.5 MPa, 7Û and 60 mm, respectively, large size billets with fine texture and diameter of 500 mm can be produced.

Traffic Environmental Capacity and MFD Based Traffic Emission Dynamic Control Model

“…According to the national grade II air quality standard defined in "Ambient Air Quality Standard (GB3095-2012)", the CO value is set to be 10.0 mg/m 3 . The contribution rate of vehicle pollutant concentration for CO is set to be 74.1% [32]. According to Nanjing's meteorological statistics, the average wind speed ranges from 1.7 m/s to 3.3 m/s, and it predominantly an east wind, therefore, the hourly average wind speed µ = 2 m/s is adopted.…”