The effect of varied additions of five elements and holding time on the microstructure of ductile cast iron

Author

Michael Joseph Gross

Abstract

"Additions of cerium, magnesium, sulfur, lanthanum and calcium are varied according to a 2^5-2 fractional factorial design, including a centerpoint, to study the effects of these elements on the resulting microstructure of ductile cast iron as it is held at 2575°F in open air for 10 minutes. Castings are produced every minute in each experiment, and sections of these castings are examined for nodule count, chill depth, and % nodularity.

After the relationship between nodule count and chill depth is established, a factorial analysis is performed to find those factors that maximize nodule count over time. A thorough examJnation of the errors affecting the analysis, including measurement and experimental errors, is presented. A cerium-magnesium interaction and lanthanum itself are found to affect nodule count. Next, a factorial analysis to determine those factors which affect nodularity over time is presented. Again, there is an examination of the errors impacting this analysis. A cerium-magnesium interaction and magnesium itself are found to affect nodularity over time. Furthermore, magnesium and cerium fade rates in each of the experiments are evaluated to determine the effect of the various additions on minimizing fade, and the highest fade rates observed in both cases were from experiments with higher initial base sulfur levels. Finally, there is a general discussion on those microstructures which exhibit high nodule counts, low chill depth, and high nodularity over time, drawing on the results from the factorial analyses"--Abstract, p. iv

Advisor(s)

Donald R. Askeland

Committee Member(s)

Thomas J. O'Keefe
Raymond M. Kluczny

Department(s)

Materials Science and Engineering

Degree Name

M.S. in Metallurgical Engineering

Publisher

University of Missouri--Rolla

Publication Date

Fall 1994

Pagination

xiii, 116 pages

Note about bibliography

Includes bibliographical references (pages 41-42)

Rights

© 1994 Michael Joseph Gross, All rights reserved.

Document Type

Thesis - Restricted Access

File Type

text

Language

English

Thesis Number

T 6870

Print OCLC #

32793491

Recommended Citation

Gross, Michael Joseph, "The effect of varied additions of five elements and holding time on the microstructure of ductile cast iron" (1994). Masters Theses. 1390.
https://scholarsmine.mst.edu/masters_theses/1390