Masters Theses

Keywords and Phrases

3rd Generation; Advanced High Strength Steel; AHSS; Dip Test; Rapid Solidification

Abstract

"A dip tester was designed and built at Missouri University of Science and Technology to test the effects of the primary alloying elements (Mn, Si, and Al) of Fe-Mn-Al-Si-C type 3rd generation advanced high strength steel (AHSS) alloys, dipping superheat, and dipping speed on the heat transfer during rapid solidification. The difficulties associated with casting 3rd generation AHSS were compiled as well to serve as a best-practices guide. An extensive list of potential 3rd generation AHSS alloys was developed and tested, and the effects of various dip testing parameters were examined.

Manganese was found to increase the heat flux by coating the copper blocks with MnO, reducing the air gap and improving the thermal conduction. Aluminum increased the heat flux by shifting the solidification path through multiple phase fields and thereby increasing the amount of enthalpy (heat) rejected upon solidification. The consequences however, were an increase in the secondary dendrite arm spacings and segregation within the microstructure resulting from a longer freezing range. Silicon was found to have no effect on the heat flux. It provided no substantial shift of the solidification path, nor did it increase the heat flux by improving the contact between the melt and copper blocks. Increasing the dipping superheat increased the heat flux by decreasing the melt viscosity and improving the wettability between the melt and copper blocks. An increase in the superheat also increased the driving force for heat transfer from the solidifying sample to the copper blocks"--Abstract, page iii.

Advisor(s)

Richards, Von

Committee Member(s)

Van Aken, David C.
O'Malley, Ronald J.

Department(s)

Materials Science and Engineering

Degree Name

M.S. in Metallurgical Engineering

Sponsor(s)

Castrip, LLC

Publisher

Missouri University of Science and Technology

Publication Date

2015

Pagination

xi, 79 pages

Note about bibliography

Includes bibliographical references (pages 72-78).

Rights

© 2015 Kramer Michael Pursell, All rights reserved.

Document Type

Thesis - Open Access

File Type

text

Language

English

Thesis Number

T 11134

Electronic OCLC #

1003210533

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Metallurgy Commons

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