What Is a Hard Steel Wire?
A hard steel wire is usually made by heat-treating a steel wire rod and then cold-working it, such as drawing.
The term “hard steel” is used to classify steels based on their hardness.
Although often compared to piano wire, piano wire is a high-grade material with strict standards and superior strength, while hard steel wire is a relatively inexpensive general material that is often used in everyday products. Examples of applications include springs for furniture such as chairs and beds, as well as springs for toys, shutters, and bicycles.
Uses of Hard Steel Wires
Hard steel wires are mainly used as springs, needles, and spokes. For example, springs for safety pins, switches, scales, bicycle saddles, etc.
In addition, hard steel wires are used in familiar everyday items such as reinforcements for high-pressure rubber hoses, screwdriver materials, hairpins, etc. In the construction industry, it is also used as shutter springs. In the automotive industry, they are used as seat springs, and in the electronics field, they are used in a wide range of industries as reinforcement for communication lines and power transmission lines.
Types of Hard Steel Wires
There are 21 types of hard steel wire rods used to make hard steel wires, depending on the amount of carbon they contain and their composition. However, hard steel wires made from these wire rods are classified into three types: Type A (SW-A), Type B (SW-B), and Type C (SW-C), with tensile strength increasing in the order of A < B < C. Each type is explained below.
- Hard Steel Wire Type A (SW-A)
This type has the lowest tensile strength among hard steel wires and is rarely used for springs. - Hard Steel Wire Type B (SW-B)
Tensile strength is higher than that of Type A. 60 carbon is widely used as wire material. It is mainly used for springs under static load. - Hard Steel Wire Type C (SW-C)
Tensile strength is even higher than that of Type B, and 80 carbon is used as wire material. Like SW-B, it is mainly used for springs under static load.