Stainless Steel Material Specification Available
Stainless steel fasteners are generally specified by their steel grade classification.
However, in Japan, it is possible to specify the exact material in some cases.
This is because there are multiple material and wire drawing manufacturers operating domestically.
For example, in the A2 stainless steel classification, the most commonly used material by fastener manufacturers is SUS XM7, which is known for its excellent workability and wide availability in the market. SUS XM7 is a type of 304 stainless steel with copper (Cu) added to enhance cold workability and is globally distributed.
However, in certain industries, the use of XM7, which contains copper, is prohibited.
As a result, alternative A2-class materials must be selected. In Japan, a wide range of other A2 materials such as SUS304, SUS305, and SUS305J1 are readily available, allowing users to specify the material according to their requirements.
SUS304L is an A2-grade stainless steel with a lower carbon (C) content. Austenitic stainless steels are prone to intergranular corrosion when exposed to high temperatures, but 304L helps prevent intergranular corrosion due to its reduced carbon content.
In the A4 grade category, represented by SUS316 (ANSI 316), not only SUS316 but also other variants such as 316L, which offers improved resistance to intergranular corrosion, and 316J1, which contains copper for better workability, are available.
This flexibility in material specification is a unique advantage of Made-in-Japan fasteners, supported by the presence of multiple high-quality material suppliers within the country.
【Writer】Tak Saima/CEO, Technical Sales