Title:
DIE STEEL HAVING EXCELLENT MIRROR FINISH PROPERTIES
Document Type and Number:
WIPO Patent Application WO/2023/085137
Kind Code:
A1
Abstract:
The present invention has an area ratio of 0.00016% or less of nonmetal inclusions with an equivalent circle diameter of 8.0 μm or more in a steel material cross section and includes 2 mass% or more of a component that is a nonmetal inclusion with an equivalent circle diameter of 5.0 μm or more selected from the group consisting of Al, Mg, and Ca. When [Ca], [Mg], and [Al] represent the respective contents (mass%) of [Ca], [Mg], and [Al] and X = [Ca]/([Mg]+[Al]), the number density of inclusions with an X value of less than 0.3 is 0.60/100 mm2 or more and less than 8.0/100 mm2, and the number density of inclusions with an X value of 0.3 or more is less than 3.0/100 mm2. In this way, it is possible to obtain a die steel having excellent wear resistance, mirror finish properties, and specular properties suitable for forming an ultra-specular plastic product.
Inventors:
ONOE TAKAHIRO
KAJIWARA TAIJU
UEDA NAOKI
KAJIWARA TAIJU
UEDA NAOKI
Application Number:
PCT/JP2022/040568
Publication Date:
May 19, 2023
Filing Date:
October 28, 2022
Export Citation:
Assignee:
NIPPON KOSHUHA STEEL CO LTD (JP)
International Classes:
C21D9/00; C22C38/00; C22C38/46
Foreign References:
| JP2015168850A | 2015-09-28 | |||
| JP2017171983A | 2017-09-28 | |||
| JP2015045071A | 2015-03-12 | |||
| JP2007009321A | 2007-01-18 | |||
| JPH08100223A | 1996-04-16 |
Attorney, Agent or Firm:
FUJIMAKI Masanori (JP)
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