Modeling of porosity during spray forming

The effects of processing parameters on porosity in spray formed materials are investigated in the present paper using a recently developed porosity model. The calculated results showed that processing parameters such as melt superheat, deposition distance, atomization pressure and melt flow rate all have significant influence on the level of porosity. The variations of porosity with these parameters consistently exhibit distinctive V-shapes. When the low porosity is considered the main criterion to characterize the quality of a deposited material, corresponding optimal processing parameters can be determined based on the calculated results. Such processing parameter combinations are not unique, however, the other constraints, such as economical and microstructural issues, should be taken into consideration as well. (C) 1997 Elsevier Science S.A.