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 7° 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, 7° and 60 mm, respectively, large size billets with fine texture and diameter of 500 mm can be produced.

Keywords

spray deposition / large size billet / atomizer / swing angle / eccentric offset

References

[1] GrantP. S.. Solidification in spray forming [J]. Metallurgical and Materials Transactions A: Physical Metallurgy and Materials Science, 2007, A38(7): 1520-1529

[2] ZhouY.-z., WuY., LaverniaE. J.. Process modeling in spray deposition: A review [J]. International Journal of Non-Equilibrium Processing, 1997, 10(2): 95-183

[3] XiaoY.-d., LiM., ZhongJ., LiW.-x., MaZ.-qing.. Devitrification behaviour of rapidly solidified Al₈₇Ni₇Cu₃Nd₃ amorphous alloy prepared by melt spinning method [J]. Journal of Central South University of Technology, 2007, 14(3): 285-290

[4] TanD.-q., LiW.-x., XiaoY.-d., WangC.. Precipitated phases and thermodynamic analysis during solidification of Al-Fe-X system at slow cooling rate [J]. Transactions of Nonferrous Metals Society of China, 2003, 13(5): 1133-1136

[5] YuanW.-h., ChenZ.-h., XuH.-y., ZhangF.-q., FuD.-fa.. Properties and microstructure of 7075/SiC_p composites prepared by spray deposition [J]. Transactions of Nonferrous Metals Society of China, 2003, 13(5): 1160-1163

[6] ZhanX.-j., LiW.-x., TanD.-q., WangR.-c., DingR.-hui.. Preparation technology of 6066/SiC_p billet by spray co-deposition with scanning atomizer to and fro [J]. Light Alloy Fabrication Technology, 2004, 32(6): 43-46

[7] BaiZ.-h., LiW.-x., WangR.-chu.. Study on the extrusion process of spray-deposition SiC_P/Al composite and 6066 Al alloy [J]. Aluminum Fabrication, 2003, 150(3): 27-33

[8] SrivastavaA. K., OjhaS. N., RanganathanS.. Microstructure feature and heat flow analysis of atomized and spray-formed Al-Fe-V-Si alloy [J]. Metallurgical and Materials Transactions A: Physical Metallurgy and Materials Science, 1998, A29(8): 2205-2218

[9] EllendtN., SchmidtR., KnabeJ., HeneinH., UhlenwinkelV.. Spray deposition using impulse atomization technique [J]. Materials Science and Engineering A, 2004, A383(1): 107-113

[10] TanD.-q., LiW.-x., XiaoY.-d., WangR.-c., MaZ.-q., XiongB.-q., ZhuB.-h., ZhangY.-an.. Phase transition of Al-Fe-V-Si heat resistant alloy by spray deposition [J]. Transactions of Nonferrous Metals Society of China, 2003, 13(3): 568-573

[11] YangZ.-wen.. Perturbation analysis of extrusion of porous metal materials [J]. Applied Mathematical Modelling, 1995, 19(10): 601-612

[12] GrantP. S., CantorB., KatgermanL.. Modelling of droplet dynamic and thermal histories during spray forming (II): Effect of process parameters [J]. Acta Metallurgica et Materialia, 1993, 41(11): 3109-3118

[13] PrydsN. H., HattelJ. H., PedersenT. B., ThorborgJ.. An integrated numerical model of the spray forming process [J]. Acta Materialia, 2002, 50(16): 4075-4091

[14] GrantP. S.. Spray forming [J]. Progress in Materials Science, 1995, 39(4): 497-545

[15] CuiC. S., FritschingU., SchulzA., LiQ. C.. Mathematical modeling of spray forming process of tubular performs (Part 1): Shape evolution [J]. Acta Materialia, 2005, 53(9): 2765-2774

[16] PrydsN. H., HattelJ. H.. Spray forming: A numerical investigation of the influence of the gas to melt ratio on the billet surface temperature [J]. International Journal of Thermal Sciences, 2005, 44(6): 587-597

[17] HattelJ. H., PrydsN. H.. A unified spray forming model for the prediction of billet shape geometry [J]. Acta Materialia, 2004, 52(18): 5275-5288

[18] SahuS. N., HarikishoreS., KoriaS. C.. Solidification behaviour of droplets in spray deposition [J]. Powder Metallurgy, 2005, 48(3): 270-276