Black Oxide

Grade	Thickness (µm)	Salt Spray (h)	Max Temp (°C)	HE Risk	Standards
Fe/BO	0.5–2.0	4	130	✅ No	DIN933ISO4017DIN934ISO4032

🔴 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)

Specifications