Masters Theses

Keywords and Phrases

Automated inclusion analysis

Abstract

"Centrifugal casting provides the opportunity of combining large centrifugal forces and directional solidification to reduce non-metallic inclusions in the cast steel product. Calcium treatment in the ladle has the potential of reducing and modifying non-metallic inclusions to achieve better machinability and mechanical properties. The objective of this research is to analyze the combined effects of calcium wire ladle treatment and centrifugal casting on the number, size, composition and morphology of non-metallic inclusions in centrifugally cast steel products. All experiments were completed at an industrial foundry. The experiments involved feeding calcium wire into the ladle after argon oxygen decarburization (AOD) and prior to centrifugal casting. Samples were collected throughout the ladle treatment process and from the centrifugally cast products. Inclusions analysis was performed using an ASPEX automated inclusion analyzer. Charpy impact testing was performed after heat treatment to evaluate the relationship between toughness and non-metallic inclusions on the centrifugally cast products. It was found that the efficiency of calcium wire fed just prior to casting was slightly higher than calcium fed at earlier stages of the ladle treatment (just after AOD), providing better Ca- reactions with the melt. Alumina (Al₂O₃) inclusions were transformed into low melting point calcium aluminates (12CaOʺ7Al₂O₃ and CaOʺAl₂O₃), but the cleanliness of the centrifugally cast products depended more on the centrifugal forces applied to the system than on the calcium wire ladle treatment"--Abstract, page iii.

Advisor(s)

Peaslee, Kent D., 1956-2013

Committee Member(s)

Lekakh, S. N. (Semen Naumovich)
Richards, Von

Department(s)

Materials Science and Engineering

Degree Name

M.S. in Metallurgical Engineering

Sponsor(s)

Steel Founders' Society of America
Benét Laboratories

Publisher

Missouri University of Science and Technology

Publication Date

Fall 2011

Pagination

xv, 88 pages

Note about bibliography

Includes bibliographical references (pages 218-220).

Rights

© 2011 Edith Yolanda Martinez Silva, All rights reserved.

Document Type

Thesis - Open Access

File Type

text

Language

English

Library of Congress Subject Headings

Calcium -- Thermal properties
Centrifugal casting
Steel castings -- Testing

Thesis Number

T 9936

Print OCLC #

794684477

Electronic OCLC #

772461034

Included in

Metallurgy Commons

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