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2008 Vanadium Award - Most Outstanding Paper

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Date08-08-05 20:33 Hit7,555

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The Vanadium Award, recognizing one of the most outstanding papers on materials science, Dr. Young-Min Lee and
Byoungchul Hwang at the Korea Institute of Materials Science(KIMS) and Professors Nack J. Kim and Sunghak Lee of Pohang
University of Science and Technology(POSTECH), achieved just. Two doctorate students started cleverly tinkering with a
research project in POSTECH (Dr. Younng-Min Lee and Dr. Byoung-Chul Hwang), successfully presented their results through their paper entitled “Effects of Molybdenum and Vanadium Addition and Tensile and Charpy Impact Properties of API X70
Linepipe Steels.”

Although the research initially started at POSTECH, the rest of the research was finished upon collaboration with KIMS. As
one of the youngest researchers receiving a Premier Award through the Institute of Materials, Minerals and Mining(IOM3), the
presence of the CEO of Vanitec (the supporting committee for the Vanadium Award), David Milborn, eight leaders of famous
steel industries, and leaders from other countries, brought an even deeper value meaning to the award.

Authors: Kim, Young-Min; Shin, Sang Yong; Lee, Hakcheol; Hwang, Byoungchul; Lee, Sunghak; Kim, Nack J.
Source: Metallurgical and Materials Transactions A, Volume 38, Number 8, August 2007 , pp. 1731-1742(12)
Abstract:
This study is concerned with the effects of V and Mo addition on tensile and Charpy impact properties of API X70 linepipe
steels. Twelve kinds of steel specimens were produced by varying V and Mo additions and rolling conditions. The addition
of V and Mo promoted the formation of acicular ferrite (AF), banitic ferrite (BF), and martensite-austenite (MA) constituents,
while suppressing the formation of polygonal ferrite (PF) or pearlite (P). The tensile test results indicated that the tensile strength of the specimens rolled in the two-phase region increased with the addition of V and Mo, while the yield strength did not vary much in these specimens, except the water-cooled specimens, which showed the increased yield strength with addition of Mo. The tensile strength of specimens rolled in the single-phase region followed by water cooling increased with increasing V and Mo contents. The yield strength, however, did not vary much with increasing V content or with addition of Mo to the low-V alloy. In these specimens, a substantial increase in the strengths was achieved only when Mo was added to the high-V alloy. The specimens rolled in the single-phase region had higher upper-shelf energy (USE) and lower ductile-brittle transition temperature (DBTT) than the specimens rolled in the two-phase region, because their microstructures were composed of AF and fine PF. According to the electron backscatter diffraction (EBSD) analysis data, the effective grain size in AF was determined by crystallographic packets composed of a few fine grains having similar orientations. Thus, the decreased DBTT in the specimens rolled in the single-phase region could be explained by the decrease in the overall effective grain size due to the presence of AF having smaller effective grain size.

About the IOM3
The history of IOM3 first began as the Iron and Steel Institute in 1869. Upon merging with the Institute of Materials and the Institute of Mining and Metallurgy in June 2002, IOM3 was born. More recent mergers include the Institute of Packaging (2006) and the Institute of Clay Technology (2006). IOM3 annually awards outstanding research results and published papers to researchers in the field of materials science in the international community. This year, 43 people were awarded, majority of whom were considered to have contributed to research developments.

Vanadium Award
The Vanadium Award is awarded through Vanitec (Vanadium International Technical Committee) and awards for the most outstanding paper metallurgy and technology of vanadium and its alloys. Unable to find an appropriate nominee for the award in 2007, the 2008 Vanadium Award included nominees from 2007-2008.