Prevention of Porosity Formation and Other Effects of Gaseous Elements in Iron Castings. (Final Report, December 2000-December 2004).

Dogan, O. N. ; Oryshchyn, D. B. ; Gundlach, R. B. ; Dunning, J. ; Maurice, D.

Technical Information Center Oak Ridge Tennessee

关键词: Iron alloys;    Alloys;    Porosity;    Solidification;    Nitrogen;   

RP-ID  :  DE2005838410

学科分类：工程和技术（综合）

美国|英语

来源: National Technical Reports Library

【 摘 要 】

Iron foundries have observed porosity primarily as interdendritic porosity in large freezing range alloys such as Ni-Hard I and hypoeutectic high Cr alloys or pinholes and fissure defects in gray and ductile irons. For most iron foundries, porosity problems occur sporadically, but even occasional outbreaks can be costly since even a very small amount of porosity can significantly reduce the mechanical properties of the castings. As a result when porosity is detected, the castings are scrapped and remelted, or when the porosity is undetected, defective parts are shipped to the consumer. Neither case is desirable. This project was designed to examine various factors contributing to the porosity formation in iron castings. Factors such as solubility of gases in liquid and solid iron alloys, surface tension of liquid iron alloys, and permeability of dendritic structures were investigated in terms of their effect on the porosity formation.