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Directional Solidification and Composite Structures

  • Merton C. Flemings
Part of the Sagamore Army Materials Research Conference Proceedings book series (SAMC, volume 14)

Abstract

Directionally solidified alloys possess any of several different types of structures depending on alloy and solidification conditions. The structures obtained include equiaxed dendrites, columnar dendrites, fibrous dendrites, cells, single crystals, and eutectic-like composite crystals.

Techniques for obtaining these different types of structures are described, and effects of the structure changes on mechanical properties are discussed. Directionally and unidirectionally solidified low alloy steel is discussed in detail. Substantial refinement of structure and improvement in properties are shown to result from rapid cooling and from directional solidification of dendritic structure, especially from unidirectional solidification. Comparable results are obtained in materials other than steel, including aluminum and magnesium alloys.

A newly developed technique is described for obtaining composite structures by plane front solidification of two-phase alloys. The technique appears to be applicable to any alloy that is poly-phase at equilibrium after solidification. Potential areas of engineering application of the technique are considered.

Keywords

Composite Structure Directional Solidification Mushy Zone Steel Casting Cent Lead 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Syracuse University Press Syracuse, New York 1968

Authors and Affiliations

  • Merton C. Flemings
    • 1
  1. 1.Massachusetts Institute of TechnologyUSA

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