Introduction to the JIS Designation System

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JIS standards are developed by the Japanese Industrial Standards Committee (JISC) in Tokyo with an aim to promote the industrial standards of Japan. The specifications begin with the prefix JIS, followed by a letter, where the letter denotes the area of division, followed by four digits. Divisions of JIS and significant standards are:

A – Civil Engineering and Architecture
B – Mechanical Engineering
C – Electronic and Electrical Engineering
D – Automotive Engineering
E – Railway Engineering
F – Shipbuilding
G – Ferrous Materials and Metallurgy
H – Nonferrous materials and metallurgy
K – Chemical Engineering etc.

Click on the below links to see standard lists for the following categories:

Iron, Structural and Constructional Steels, Stainless Steels, Coated Steels

Castings, Forgings, Welding and Filler Materials, Powder Metallurgy/Sintered Materials

Japanese JIS standards are widely used in Asia and the Pacific areas. JIS steel specifications have also often been used as a base for other national systems, such as Korean, Chinese, and Taiwanese.

Example 1 : JIS G3445 STKM11A is a low-carbon tube steel containing 0.12%C, 0.35%Si, 0.60%Mn, 0.04%P, 0.04%S;

Example 2 : JIS G4403 SKH2 (AISI T1Grade) is a tungsten high-speed tool steel containing 0.73-0.83%C, 3.8-4.5%Cr, 0.4%Mn, 0.4%Si, 0.8-1.2%V and 17-19%W.

Regarding stainless steels, Japan has generally adopted the AISI numbering system within the Japanese system i.e. SUS 304 corresponds to Type 304 stainless steel. SUH numbers serve to designate the heat-resistant alloys such a SUH 310. SCS and SCH numbers are used for stainless steel castings. Generally, the first "S" in SUS stands for Steel, "U" is "Use" (= for special uses) and the second "S" denotes "Stainless".