Accession Number : AD0695389

Title :   IMPROVEMENT OF PRODUCTION TECHNOLOGY FOR THIN-WALLED FANCY-SHAPED STAINLESS-STEEL CASTINGS,

Corporate Author : FOREIGN TECHNOLOGY DIV WRIGHT-PATTERSON AFB OHIO

Personal Author(s) : Babaskin,Yu. Z. ; Muravev,V. N.

Report Date : 03 FEB 1969

Pagination or Media Count : 14

Abstract : When casting induction-melted stainless steel of the Kh18N9TL type into dry-sand molds, the thin-wall objects do not possess a sufficient impermeability because of the appearance of primary pipes, nonmetallic-inclusion pile-ups, and Ti porosity. The usual vacuum procedure is only slightly effective for stainless steels and cannot prevent the secondary oxidation and it is rather difficult to create and to maintain a high vacuum in irregularly shaped molds. The use of the neutral and reducing media or different additives with a stabilizing action fails in this case as well. The casting properties were studied as a function of the pouring temperature and the Ti content. Some preliminary investigations seem to indicate only a slight effect of temperature. Metallographic examinations reveal a great number of nonmetallic inclusions, mainly, of Ti oxides, nitrides, and sulfides, which are either homogeneously distributed or agglomerated. On the surface of fractured samples, nonmetallic inclusions are easily detectable, their concentration being directly proportional to the Ti content. When applying oxygen blowing, the most uniform distribution of impurities is attained when the highest permissible amount of Ca-Si(0.3%) is added. (Author)

Descriptors :   (*STAINLESS STEEL, CASTING), INDUSTRIAL PRODUCTION, INDUCTION HEATING, MELTING, POROSITY, DEFECTS(MATERIALS), CASTINGS, OXIDATION, USSR

Subject Categories : Metallurgy and Metallography
      Fabrication Metallurgy

Distribution Statement : APPROVED FOR PUBLIC RELEASE