EP 4130303 A1 20230208 - FREE-CUTTING STEEL AND METHOD FOR MANUFACTURING SAME
Title (en)
FREE-CUTTING STEEL AND METHOD FOR MANUFACTURING SAME
Title (de)
AUTOMATENSTAHL UND VERFAHREN ZUR HERSTELLUNG DAVON
Title (fr)
ACIER DE DÉCOLLETAGE ET PROCÉDÉ DE FABRICATION D'UN TEL ACIER
Publication
Application
Priority
- JP 2020063741 A 20200331
- JP 2021014049 W 20210331
Abstract (en)
Provided is a free-cutting steel that, despites not containing Pb, has machinability by cutting higher than or equal to that of a low carbon sulfur-lead composite free-cutting steel. A free-cutting steel comprises: a chemical composition that contains, in mass%, C: less than 0.09 %, Mn: 0.50 % to 1.50 %, S: 0.250 % to 0.600 %, O: more than 0.010 % and 0.050 % or less, and Cr: 0.50 % to 1.50 %, with a balance consisting of Fe and inevitable impurities, and in which a A value defined by the following formula (1) is 6.0 to 18.0, and a steel microstructure in which at least 500 particles/mm<sup>2</sup> of sulfide of less than 1 µm in equivalent circle diameter and at least 2000 particles/mm<sup>2</sup> of sulfide of 1 µm to 5 µm in equivalent circle diameter are distributed.
IPC 8 full level
C21D 8/06 (2006.01); C22C 38/00 (2006.01); C22C 38/60 (2006.01)
CPC (source: EP KR US)
C21D 1/02 (2013.01 - EP); C21D 7/13 (2013.01 - EP); C21D 8/0226 (2013.01 - KR US); C21D 8/065 (2013.01 - EP KR); C21D 9/0075 (2013.01 - EP); C21D 9/0081 (2013.01 - US); C21D 9/22 (2013.01 - EP); C22C 38/001 (2013.01 - KR); C22C 38/002 (2013.01 - EP US); C22C 38/008 (2013.01 - EP); C22C 38/02 (2013.01 - EP); C22C 38/04 (2013.01 - EP US); C22C 38/06 (2013.01 - KR); C22C 38/08 (2013.01 - EP); C22C 38/12 (2013.01 - EP); C22C 38/14 (2013.01 - EP); C22C 38/18 (2013.01 - EP KR US); C22C 38/42 (2013.01 - KR); C22C 38/46 (2013.01 - KR); C22C 38/50 (2013.01 - KR); C22C 38/60 (2013.01 - EP US)
Designated contracting state (EPC)
AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR
Designated extension state (EPC)
BA ME
Designated validation state (EPC)
KH MA MD TN
DOCDB simple family (publication)
EP 4130303 A1 20230208; CN 115362278 A 20221118; CN 115362278 B 20240227; JP 7024922 B1 20220224; JP WO2021201178 A1 20211007; KR 20220144864 A 20221027; TW 202138583 A 20211016; TW I779544 B 20221001; US 2023108640 A1 20230406; WO 2021201178 A1 20211007
DOCDB simple family (application)
EP 21780703 A 20210331; CN 202180025472 A 20210331; JP 2021014049 W 20210331; JP 2021538730 A 20210331; KR 20227033225 A 20210331; TW 110112011 A 20210331; US 202117907271 A 20210331