Steel wire, a method for manufacturing the same, and method for manufacturing a spring or medical wire products
AssigneesSuzuki-Sumiden Stainless Steel Wire Co., Ltd., Suzuki Garphyttan AB
InventorsJohan Norstrom, David Thureborn, Fumito Kanno, Masaki Ishihara
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Abstract
The invention relates to a steel wire suitable for making a spring or medical wire products which remarkably improve the performance of conventional stainless steel wire. The steel comprises (in wt. %): C: 0.02 to 0.15, Si: 0.1 to 0.9, Mn: 0.8 to 1.6, Cr 16 to 20, Ni: 7.5 to 10.5, Mo: ≤3, Al: 0.5 to 2.5, Ti: ≤0.15, N: ≤0.05, optional elements, and impurities, balance Fe, wherein the total amount of Cr and Ni is 25 to 27 wt. %, and wherein the steel has a microstructure including, in volume % (vol. %), martensite: 40 to 90, austenite: 10 to 60, and delta ferrite: ≤5.
Claims16
A steel wire suitable for making a spring or medical wire products, consisting of, in weight %:
- C
- 0.02 to 0.15
- Si
- 0.1 to 0.9
- Mn
- 0.8 to 1.6
- Cr
- 16 to 20
- Ni
- 7.5 to 10.5
- Mo
- ≤3
- W
- ≤0.5
- Co
- ≤1
- Al
- 0.5 to 2.5
- Ti
- ≤0.15
- V
- ≤0.1
- Nb
- ≤0.1
- Zr
- ≤0.1
- Ta
- ≤0.1
- Hf
- ≤0.1
- Y
- ≤0.1
- N
- ≤0.05
- B
- ≤0.01
- Cu
- ≤2.5
- S
- ≤0.05
- P
- ≤0.05
- Ca
- ≤0.01
- Mg
- ≤0.01
- REM
- ≤0.2,
- and
- Fe and impurities balance,
- wherein the total amount of Cr and Ni is 25 to 27 wt. %, and
- wherein the steel wire has a microstructure including in volume %:
- martensite
- 40 to 90
- austenite
- 10 to 60, and
- delta ferrite
- ≤5.
Dependencies are inferred from the claim text.