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Title: Mechanical Properties and Fracture Surfaces of Thixoformed HP9/4/30 Steel

Abstract

Most work in semi-solid metal processing has been focused on relatively low-melting temperature materials such as aluminium, magnesium, tin, lead and their composites. Because of the high melting temperatures and related measurement difficulties, there is relatively small amount of experimental data available on the thixoforming of high temperature materials such as steels. This paper discusses the relationships between tensile tests data and the fracture surfaces of HP9/4/30 steel samples, in as-received and as-thixoformed conditions. Some of the as-thixoformed samples were subjected to commercial heat treatments before the tests were carried out. The as-received samples showed a typical ductile fracture of 'cup' and 'cone' surface appearance. The thixoformed samples, although showing some significant increase in tensile strength values, failed in a brittle manner, with the fracture surfaces showing a 'cobbled' surface appearance. The application of the commercial heat treatment to the thixoformed samples has significantly improved their ductility.

Authors:
;  [1];  [2];  [3]
  1. Department of Mechanical and Materials Engineering, National University of Malaysia, 43600 UKM Bangi, Selangor (Malaysia)
  2. Department of Engineering, University of Leicester, University Rd., Leicester, LE1 7RH (United Kingdom)
  3. Department of Engineering Materials, University of Sheffield, Hadfield Building, Mappin St., Sheffield, S1 3JD (United Kingdom)
Publication Date:
OSTI Identifier:
21056976
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 907; Journal Issue: 1; Conference: 10. ESAFORM conference on material forming, Zaragoza (Spain), 18-20 Apr 2007; Other Information: DOI: 10.1063/1.2729675; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ALUMINIUM; DUCTILITY; FRACTURES; HEAT TREATMENTS; LEAD; MAGNESIUM; MELTING POINTS; PROCESSING; SOLIDS; STEELS; SURFACES; THIXOTROPY; TIN

Citation Formats

Omar, M. Z., Jaharah, A. G., Atkinson, H. V., and Kapranos, P.. Mechanical Properties and Fracture Surfaces of Thixoformed HP9/4/30 Steel. United States: N. p., 2007. Web. doi:10.1063/1.2729675.
Omar, M. Z., Jaharah, A. G., Atkinson, H. V., & Kapranos, P.. Mechanical Properties and Fracture Surfaces of Thixoformed HP9/4/30 Steel. United States. doi:10.1063/1.2729675.
Omar, M. Z., Jaharah, A. G., Atkinson, H. V., and Kapranos, P.. Sat . "Mechanical Properties and Fracture Surfaces of Thixoformed HP9/4/30 Steel". United States. doi:10.1063/1.2729675.
@article{osti_21056976,
title = {Mechanical Properties and Fracture Surfaces of Thixoformed HP9/4/30 Steel},
author = {Omar, M. Z. and Jaharah, A. G. and Atkinson, H. V. and Kapranos, P.},
abstractNote = {Most work in semi-solid metal processing has been focused on relatively low-melting temperature materials such as aluminium, magnesium, tin, lead and their composites. Because of the high melting temperatures and related measurement difficulties, there is relatively small amount of experimental data available on the thixoforming of high temperature materials such as steels. This paper discusses the relationships between tensile tests data and the fracture surfaces of HP9/4/30 steel samples, in as-received and as-thixoformed conditions. Some of the as-thixoformed samples were subjected to commercial heat treatments before the tests were carried out. The as-received samples showed a typical ductile fracture of 'cup' and 'cone' surface appearance. The thixoformed samples, although showing some significant increase in tensile strength values, failed in a brittle manner, with the fracture surfaces showing a 'cobbled' surface appearance. The application of the commercial heat treatment to the thixoformed samples has significantly improved their ductility.},
doi = {10.1063/1.2729675},
journal = {AIP Conference Proceedings},
number = 1,
volume = 907,
place = {United States},
year = {Sat Apr 07 00:00:00 EDT 2007},
month = {Sat Apr 07 00:00:00 EDT 2007}
}
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