LC Coating (Organic Polymer Composite Dry Film)
LC dry-film coating: an organic polymer composite film giving 200 h+ protection together with dry-film lubrication.
| Finish Code | TZ304 |
|---|---|
| Environmental Grade | REACH / RoHS compliant |
| Salt Spray Standard | 200 h and above |
| Appearance / Colour | Dark grey |
| Suitable For | All types of screws, fasteners and precision metal parts |
| Features | Dry-film lubrication; corrosion resistant |
| Environmental Compliance | REACH and RoHS compliant |
Overview
Surface finishing on a fastener is a functional coating, not a cosmetic one: it sets the friction coefficient that determines how much of the applied torque becomes clamp load, and it defines how long the part survives in a corrosive environment. Two finishes that look identical can differ by a factor of several in salt-spray hours and by enough in friction to change the torque specification. This listing: finish code TZ304, salt spray 200 h and above, appearance / colour Dark grey, environmental compliance REACH and RoHS compliant.
What sets this listing apart: Environmental Grade REACH / RoHS compliant; Features Dry-film lubrication; corrosion resistant.
Advantages
Barrier coatings protect the base metal, while sacrificial coatings protect the steel even at a scratch; the choice depends on whether the joint will be damaged in service.
Hydrogen embrittlement risk separates processes: electroplating on high-strength steel needs a de-embrittlement bake, while mechanical and flake coatings avoid the risk entirely.
Friction coefficient changes with coating: a zinc-flake coating typically runs lower and more consistently than electroplated zinc, which is why torque tables are finish-specific.
Applications
Automotive underhood and body joints, outdoor equipment, marine and coastal installations, electronics hardware, and any joint where the torque specification is tied to a friction value.
Quote the standard, the hours and the acceptance criterion together — a salt-spray figure without the test method is not a specification. Check that the coating process is compatible with the core hardness of the part.
Product information is supplied by Toprecision. Custom parts can be produced to drawing — contact us for samples or a quotation.
Specifications across this series
2 parts in this series
| Part | Finish Code | Environmental Gr… | Salt Spray Stand… | Appearance / Col… |
|---|---|---|---|---|
| LC (PLC Polymer Carbon Film) · TZ029 / Low-temperature vacuum plasma deposition; no waste liquid or gas emissions. RoHS compliant / 120-300 h with a metallic interlayer | TZ029 | Low-temperature vacuum plasma deposition; no waste liquid or gas emissions. RoHS compliant | 120-300 h with a metallic interlayer | Dark grey to black |
| LC Coating (Organic Polymer Composite Dry Film) · TZ304 / REACH / RoHS compliant / 200 h and above | TZ304 | REACH / RoHS compliant | 200 h and above | Dark grey |
Values are taken from each part’s own attribute set. Changing length, material or finish changes pull-out strength and installation torque, so compare the row that matches your drawing.
Selection and test data: engagement length, standards, salt-spray hours
FAQ
What does this finish provide?
Finish Code TZ304, Environmental Grade REACH / RoHS compliant, Salt Spray Standard 200 h and above, Appearance / Colour Dark grey.
How does it affect torque and friction?
Carbon Steel.
What should I verify before ordering or installing it?
Quote the standard, the hours and the acceptance criterion together — a salt-spray figure without the test method is not a specification. Check that the coating process is compatible with the core hardness of the part.