CARBURIZING STEEL HAVING EXCELLENT COLD FORGEABILITY, AND PRODUCTION METHOD THEREOF

WIPO Patent Application WO/2012/073485

A1

The present invention provides a carburizing steel which has a composition that contains, in terms of mass percentages, 0.1 to 0.35% of C, 0.01 to 0.22% of Si, 0.3 to 1.5% of Mn, 1.35 to 3.0% of Cr, 0.018% or less of P, 0.02% or less of S, 0.015 to 0.05% of Al, 0.008 to 0.015% of N and 0.0015% or less of O within ranges that satisfy formulae (1), (2) and (3), with the remainder comprising Fe and unavoidable impurities, and in which the total structural fraction of ferrite and pearlite in the steel structure is 85% or higher and the average ferrite particle diameter is 25 μm or lower. 3.1 ≥ {([%Si]/2) + [%Mn] + [%Cr]} ≥ 2.2 --- (1) [%C] - ([%Si]/2) + ([%Mn]/5) + 2[%Cr] ≥ 3.0 --- (2) 2.5 ≥ [%Al] / [%N] ≥ 1.7 --- (3) Here, [%M] denotes the content (mass %) of an element M.

ICHIMIYA, Katsuyuki (JFE STEEL CORPORATION 2-3, Uchisaiwai-cho 2-chome, Chiyoda-k, Tokyo 11, 〒1000011, JP)
一宮　克行 (〒11 東京都千代田区内幸町二丁目２番３号　ＪＦＥスチール株式会社　知的財産部内 Tokyo, 〒1000011, JP)

JP2011/006655

June 07, 2012

November 29, 2011

Click for automatic bibliography generation  

JFE STEEL CORPORATION (2-3 Uchisaiwai-cho 2-chome, Chiyoda-ku Tokyo, 11, 〒1000011, JP)
ＪＦＥスチール株式会社 (〒11 東京都千代田区内幸町二丁目２番３号 Tokyo, 〒1000011, JP)
ICHIMIYA, Katsuyuki (JFE STEEL CORPORATION 2-3, Uchisaiwai-cho 2-chome, Chiyoda-k, Tokyo 11, 〒1000011, JP)

C22C38/00; C21D8/00; C22C38/18; C22C38/48; C21D1/32

SUGIMURA, Kenji (36F Kasumigaseki Common Gate West, 3-2-1 Kasumigaseki, Chiyoda-k, Tokyo 13, 〒1000013, JP)

View/Download PDF      PDF Help

Previous Patent: THERMAL CYCLER AND THERMAL CYCLE METHOD

Next Patent: AIR COMPRESSION UNIT, SOLAR LIGHT TRACKING SYSTEM, AND WATER SUPPLY SYSTEM