Accession Number : AD0696457

Title :   MICROSTRUCTURAL - MECHANICAL PROPERTY RELATIONSHIPS IN HIGH STRENGTH CAST STEELS.

Descriptive Note : Interim rept. 1 Jan 68-21 Jun 69,

Corporate Author : CASE WESTERN RESERVE UNIV CLEVELAND OHIO DIV OF METALLURGY AND MATERIAL SCIENCE

Personal Author(s) : Peck,J. V. ; Bertolo,R. B. ; Wallace,J. F.

Report Date : AUG 1969

Pagination or Media Count : 92

Abstract : The grain refinement of high strength steel castings by small titanium additions has been enhanced by a small particle nucleation technique. The combination of these two mechanisms makes possible the total refinement of large castings inoculated with 0.1% titanium. The fatigue properties of high strength columnar steel castings tested parallel to the chill were found to be influenced by the solidification time (mass effect). Low values of endurance limit and endurance ratio were observed in tests conducted transverse to the solidification direction. Titanium carbonitrides and titanium sulfide inclusions which are by-products of the titanium inoculation exerted little or no influence on fatigue properties although titanium sulfide severely reduced tensile ductility. Utilization of appropriate vacuum melting and casting techniques reduced the volume of non-metallic inclusions. When a sufficiently high thermal gradient is employed during solidification together with proper vacuum melting and casting, the usual loss of ductility with increasing solidification time is markedly reduced. (Author)

Descriptors :   (*CASTINGS, *STEEL), (*METALLOGRAPHY, STEEL), REFINING(METALLURGY), CASTING, GRAIN STRUCTURES(METALLURGY), MELTING, MECHANICAL PROPERTIES, NUCLEATION, DEFECTS(MATERIALS), TITANIUM, TITANIUM COMPOUNDS, ADDITIVES, MICROSTRUCTURE, DUCTILITY, FATIGUE(MECHANICS)

Subject Categories : Properties of Metals and Alloys
      Fabrication Metallurgy
      Solid State Physics

Distribution Statement : APPROVED FOR PUBLIC RELEASE