304 Stainless Steel Strip 1/4H 1/2H 3/4H FH Thickness 0.4mm 0.5mm 0.6mm Spring Belt

The different hardness states of 304 stainless steel strip (1/4H, 1/2H, 3/4H, FH) are mainly achieved through cold rolling processing, and the increase of hardness is accompanied by the decrease of plasticity and toughness. The following are the introduction, parameters, properties and applications of each hardness state:

1. 1/4H (1/4 Hard)

• Hardness: HV 250-310
• Tensile strength: 700-850 MPa
• Elongation: 10-15%
• Properties: mild cold rolling, moderate hardness, both a certain degree of plasticity and toughness.
• Application: Suitable for occasions requiring certain strength and formability, such as architectural decoration, home appliance parts, etc.

2. 1/2H (1/2 Hard)

• Hardness: HV 310-370
• Tensile strength: 850-1000 MPa
• Elongation: 5-10%
• Performance: medium cold rolling, high hardness, plasticity and toughness decreased.
• Application: For applications requiring high strength and moderate formability, such as spring pieces, auto parts, etc.

3. 3/4H (3/4 Hard)

• Hardness: HV 370-430
• Tensile strength: 1000-1150 MPa
• Elongation: 3-8%
• Performance: high cold rolling, further increase in hardness, plasticity and toughness further reduced.
• Application: Suitable for high strength, low formability requirements, such as high strength springs, precision parts, etc.

4. FH (Full Hard)

• Hardness: HV 430 or more
• Tensile strength: 1150-1300 MPa
• Elongation: 1-3%
• Performance: Maximum cold rolling, highest hardness, lowest plasticity and toughness.
• Application: It is used in applications requiring very high strength and almost no molding, such as blades and high-strength structural parts.

How to Choose different Hardness Type

• 1/4H: mild cold rolling, suitable for occasions requiring certain formability.
• 1/2H: Medium cold rolling, suitable for high strength and moderate formability occasions.
• 3/4H: high cold rolling, suitable for occasions with high strength and low formability requirements.
• FH: Maximum cold rolling, suitable for extremely high strength, almost no molding.

The selection must balance strength, hardness and formability according to the specific application needs.