Learn the Rules for Metal Material Codes! The Meaning and Reading of JIS Codes Explained

Metal Materials Are Divided Into Two Types: "Iron and Steel" and "Non-Ferrous Metals"

Used as industrial materials, metal materials can be broadly classified into two categories: "iron and steel" and "non-ferrous metals." Iron and steel is one of the most commonly used materials, accounting for the majority of all metal materials. Iron and steel are abundant resources and are relatively inexpensive. They are characterized by their excellent strength and workability. Their properties can also be adjusted through heat treatment.

Non-ferrous metal materials, on the other hand, are used to take advantage of properties that iron and steel materials do not have, such as light weight (aluminum, magnesium), electrical conductivity (copper), and corrosion resistance (titanium).

Meaning of JIS Material Codes

JIS material codes specify the following key properties of metal materials.

Specifically, JIS material codes can be divided into the following three elements.

Why Are Material Codes Established?

One of the reasons for establishing JIS material codes is to efficiently express the properties and applications of materials, helping prevent confusion in manufacturing and transactions. Material codes make it possible to quickly assess a material's basic properties (strength, corrosion resistance, etc.) and intended use, and are useful for choosing appropriate materials and setting machining conditions.

Standardized codes also facilitate clearer communication in international trade.

What are the JIS standards?
The Japanese Industrial Standards (JIS) are national standards that define specifications and measurement methods for industrial products in Japan. Originally developed as standards for industrial products, JIS now plays a central role in standardizing a wide range of fields, including information processing and services. Its goals include ensuring compatibility across products and services, guaranteeing quality and safety, and improving production efficiency.

Material Code Rules for Iron and Steel

As discussed above, the codes for iron and steel materials mainly consist of three elements: material, product name, and number.

For example, for the structural steel material "SS400," the first "S" stands for steel, the second "S" stands for structure, and the "400" indicates a minimum tensile strength of 400 N/mm². Similarly, in the case of carbon steels for machine structural use "S45C," the "S" stands for steel, and the "45C" indicates a carbon steel with a carbon content of 0.45%.

List of Iron and Steel Material Codes

Examples of types and codes for iron and steel materials are given below.

Structural steels

Machine structural steels

Tool steels

Material Code Rules for Non-Ferrous Metal

Similar to iron and steel, the codes for non-ferrous metal materials are systematically defined. Aluminum begins with "A" and copper with "C," followed by a code indicating the alloy type and shape.

As a general rule, the designation for aluminum consists of an A followed by "a four-digit number indicating the alloy type" and "a letter indicating the shape." The same applies to copper, where C is followed by "a four-digit number indicating the alloy type" and "a letter indicating the shape."

The final letter in the code, which indicates the shape, includes "P" (plate), "B" (rod), "T" (tube), and "W" (wire).

List of Non-Ferrous Metal Material Codes

Examples of types and codes for non-ferrous metal materials are given below.

Aluminum

Copper

Others

JIS Material Codes Are Essential Information on the Manufacturing Floor

JIS material codes are essential information for efficiently selecting materials and conducting transactions. They begin with "F" or "S" for iron and steel materials, and "A" (aluminum) or "C" (copper) for non-ferrous metals. These codes are designed to convey material type, application, and properties at a glance. Understanding this symbol system improves work efficiency on the manufacturing floor, particularly in material selection and quality control. However, material codes only indicate basic properties. Actual use of materials must also consider factors such as heat treatment conditions, machining methods, and the usage environment. Furthermore, as technological advances continue to drive the development of new materials and machining methods, it's essential to stay informed and up to date with the latest information.