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Black Oxide
Specifications
Thickness Range
0.5–2.0 µm
Typical Thickness
1.0 µm
Salt Spray
4 h
Max Temperature
130 °C
Corrosion Class
Fe/BO
Thread Class
6g
HE Risk
✅ No
Grade Variants
Grade
Thickness (µm)
Salt Spray (h)
Max Temp (°C)
HE Risk
Standards
Fe/BO
0.5–2.0
4
130
✅ No
DIN933
ISO4017
DIN934
ISO4032
Constraint Rules
🔴 RULE_COATING_CONFLICT
Coating Compatibility — Ensure the selected finish is supported by the target standard
🟠 RULE_CORROSION_CHECK
Corrosion Resistance — Ensure the coating's salt spray hours meet the environmental corrosion class requirements
🔴 RULE_HE_RISK
Hydrogen Embrittlement Risk — Warning for high-strength bolts (≥1000 MPa) using acid pickling process
🟡 RULE_TEMP_LIMIT
Temperature Limit — Ensure the operating temperature does not exceed the coating's maximum service temperature
🟠 RULE_THREAD_FIT
Thread Fit — Ensure coating thickness does not exceed the thread tolerance allowance
🟠 RULE_COATING_THICKNESS
Coating Thickness — Ensure the actual coating thickness is within the standard allowable range
🔴 RULE_ISO4042_C2D_HEX_CHROME
ISO 4042 C2D Hexavalent Chromium Warning — C2D uses Cr⁶⁺ passivation, restricted by RoHS/REACH
🟡 RULE_ISO4042_CODE_DECODE
ISO 4042 Coating Code Validation — Ensure coating code format is correct (C/D/E/F + thickness class + passivation type)