M5×30 Countersunk Machine Zinc Plating Screw

Description

 M5×30 Countersunk Machine Zinc Plating Screw

specifications for a standard M5×30 Countersunk Machine Screw with Zinc Plating:

M5×30 Countersunk Machine Screw – Key Specifications

Standard: ISO 2009-2011 / DIN 965
Material: Steel (typically carbon steel)
Finish: Zinc plating (usually blue/yellow chromate passivation)

1. Dimensional Specifications

• Diameter (M5): 5mm (thread major diameter)

• Length: 30mm (under head length)

• Head Type: Countersunk (flat head, 90° included angle)

• Head Diameter: 9.2mm (typical)

• Head Height: 2.6mm (typical)

• Thread Pitch: 0.8mm (standard coarse thread)

• Drive Type: Cross recess (Phillips) or Slot

2. Mechanical Properties

• Strength Class: 4.8 (most common) or 8.8 (high strength)

  • 4.8: Tensile strength = 400 MPa, Yield strength = 320 MPa

  • 8.8: Tensile strength = 800 MPa, Yield strength = 640 MPa

• Hardness:

  • 4.8: HV 130–180

  • 8.8: HV 250–320

3. Corrosion Protection

• Zinc Plating: Typically 5–8µm thickness

• Passivation:

  • Blue clear (most common)

  • Yellow chromate (higher corrosion resistance)

• Salt Spray Test:

  • White rust: ≥48 hours

  • Red rust: ≥72 hours (yellow chromate)

4. Installation Specifications

• Countersink Angle: 90° (ISO/DIN standard)

• Recommended Hole Size:

  • Clearance hole: 5.5mm (for M5 thread)

  • Countersink diameter: 9.2mm (min) × 90°

• Torque Settings (for 4.8 grade):

  • Steel-to-steel: 4–5 Nm

  • Aluminum-to-aluminum: 3–4 Nm

5. Applications

• Electronics enclosures

• Machinery assembly

• Automotive components

• General manufacturing