- Challenging Limits: A Material that Achieves the Balance of Two Contradictory Properties -
NIPPON KINZOKU CO., LTD. (TOKYO: 5491) (Headquarters: Minato-ku, Tokyo) is proud to introduce “NK-301ZF”, spring-use stainless steel that achieves both excellent processability and high strength within the chemical composition range of SUS301 (JIS), as part of its environmentally conscious “Eco-Product” series. This material has been widely adopted in various industries, including the automotive, electronic components, and semiconductors sectors.
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NK-301ZF combines high strength with high ductility, enabling both weight reduction of parts and simplification of manufacturing processes. These characteristics have led to its adoption in a wide range of applications, including smartphone components, diaphragm, and flat spiral spring.
NK-301ZF combines high strength with high ductility, enabling both weight reduction of parts and simplification of manufacturing processes. This contributes to improved energy efficiency and reduced environmental impact throughout the customer's entire manufacturing process. Additionally, its enhanced design flexibility allows for optimization of shapes and specifications, leading to improved processing efficiency and yield. These characteristics have led to its adoption in a wide range of applications.
At our company, NK-301ZF is designated as an “Eco-Product” based on these considerations. We are committed to sustainable manufacturing through the promotion of environmentally friendly materials, with the goal of achieving Net Zero CO₂ emissions by 2050.
This product was developed in accordance with NIPPON KINZOKU's 11th business plan, “NIPPON KINZOKU 2030”, which is focused on the key concept of “Near Net Performance" -achieving the performance required by end products through material design. Our objective is to further expand its sales in the automotive, electronic components, semiconductors, and related markets.
Features
1. Chemical Composition
The chemical composition is adjusted to meet the JIS standard range.
https://www.nipponkinzoku.co.jp/assets/images/2025/05/Chemical-Composition.pdf
2. Mechanical Property
Compared to conventional SUS301, NK-301ZF has greater elongation, helping to prevent cracking during forming. It is also a high-strength material that can achieve a hardness level of HV580 or higher.
https://www.nipponkinzoku.co.jp/assets/images/2025/05/Mechanical-Properties.pdf
At equivalent strength levels, it offers higher elongation and superior ductility to conventional SUS301.
https://www.nipponkinzoku.co.jp/assets/images/2025/05/Relationship-Between-Hardness-and-Elongation.pdf
3. Fatigue Resistance, Processability
We controlled the inclusions in the steel, which significantly reduced the amount of macroscopic nonmetallic inclusions.
https://www.nipponkinzoku.co.jp/assets/images/2025/05/Image-of-Inclusions.pdf
Consequently, we anticipate improved fatigue resistance.
https://www.nipponkinzoku.co.jp/assets/images/2025/05/MIT-test-results.pdf
Click here for the full text.
https://www.nipponkinzoku.co.jp/assets/images/2025/05/Introducing-NK-301ZF-A-Breakthrough-Material-Combining-High-Strength-and-High-Ductility.pdf
About NIPPON KINZOKU Group
Our products have been used in a range of areas from the precision field to the construction industry. https://www.nipponkinzoku.co.jp/en/
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Contacts
Production Process & Support Dept.
NIPPON KINZOKU CO., LTD.
Email: sisaku-sc@nipponkinzoku.co.jp
https://www.nipponkinzoku.co.jp/en/inquiry