Liberfitting Logo
Surface Engineering Division

Surface Treatment
Technology

Four engineered surface treatments -- each optimized for a specific corrosion environment. From 96-hour standard protection to 700+ hour extreme-duty zinc-nickel alloy plating.

700+h Max Salt Spray
4 Treatment Types
SGS Tested & Certified
CE / ISO Certified Facility

// Protection Index

Zinc-Nickel 700+ h
CR3+ Zinc 96+ h
Black Oxide 24-48 h
Anti-Rust Oil Temp.
ASTM B117 Salt Spray Test

Corrosion Resistance
Duration Comparison

All treatments tested to ASTM B117 neutral salt spray standard. Results represent time to first white corrosion appearance on finished parts.

Zinc-Nickel Alloy
700+ h
700+ hrs
SGS Verified Extreme Corrosion Duty RoHS Compliant
CR3+ Zinc Plating
96+ h
96+ hrs
SGS Tested Trivalent Chromium + Sealant Topcoat
Black Oxide
24-48 h
24-48 hrs
Low-Reflectance Dimensional Neutral + Oil Required
Anti-Rust Oil
Temp.
Temp.
Storage/Transit Renewable Non-Permanent
0 h 175 h 350 h 525 h 700+ h
← Salt Spray Duration (ASTM B117) →

Treatment Comparison Matrix

Side-by-side technical comparison across key performance parameters. Select the treatment matched to your operating environment and pressure requirements.

Parameter CR3+ Zinc + Sealant BEST Zinc-Nickel Alloy Plating Black Oxide Blackening Anti-Rust Oil Protective
Salt Spray Duration 96+ h 700+ h 24-48 h (with oil) Temporary
Coating Type Electroplated Zinc + CR3 Passivation + Sealant Zn-Ni Alloy Electroplate (12-15% Ni) Chemical Conversion (Fe₃O₄ layer) Petroleum-based Rust Inhibitor Film
Appearance
Silver / Iridescent
Dark Silver-Grey
Matte Black
Natural / Oily
Dim. Impact +8-12 µm +8-15 µm ~0 µm ~0 µm
RoHS / REACH Compliant Compliant Compliant Compliant
Relative Cost
Medium
Premium
Low
Lowest
Best For General hydraulics, standard OEM assemblies Agriculture, marine, offshore, mining Precision fittings, optical/low-glare needs Storage, transit protection, short-term

Application Scenarios

Match your operating environment to the right surface treatment. Each scenario maps to specific corrosion challenges and recommended specifications.

Agriculture

Tractors, harvesters, sprayers exposed to fertilizer, pesticide, and moisture cycles.

Recommended

Zinc-Nickel 700+h
Fertilizer Resist. Seasonal Cycles

Marine / Offshore

Salt-spray, high-humidity, and chloride-rich environments. Offshore platforms, marine cranes.

Recommended

Zinc-Nickel 700+h
Salt Spray Chloride Resist.

Mining

Underground equipment, drilling rigs, and conveyors facing abrasive slurry and acidic water.

Recommended

Zinc-Nickel CR3+ Zinc
Acid Resist. Abrasion

Outdoor / Industrial

Construction equipment, municipal vehicles, and general OEM assemblies with UV and weather exposure.

Recommended

CR3+ Zinc Black Oxide
Weather Cycles Cost-Effective

Process Sample Close-Ups

Drag the slider to compare raw machined surface vs. finished treated surface. Each sample represents a production-run hydraulic fitting from our facility.

After -- CR3+ Zinc Before -- Raw Raw machined hydraulic fitting before CR3+ zinc plating
Hydraulic fitting after CR3+ zinc plating with silver iridescent finish

← Drag to compare raw vs. finished surface →

CR3+ Zinc Plating

+ Sealant Topcoat

Salt Spray 96+ hours
Passivation Trivalent Chromium
Topcoat Sealant Applied
Thickness 8-12 µm
Compliance RoHS / REACH

Ideal Applications

Standard OEM Hydraulics Construction Equipment Industrial Assemblies General Distribution
After -- Zn-Ni Before -- Raw Raw machined hydraulic fitting before zinc-nickel plating
Hydraulic fitting after zinc-nickel alloy plating with dark grey finish

← Drag to compare raw vs. finished surface →

Zinc-Nickel Alloy

Best

Maximum Corrosion Protection

Salt Spray 700+ hours
Nickel Content 12-15%
Thickness 8-15 µm
Appearance Dark Silver-Grey
Compliance RoHS / REACH

Ideal Applications

Agriculture / Sprayers Marine / Offshore Mining Equipment Oil & Gas
After -- Black Oxide Before -- Raw Raw machined hydraulic fitting before black oxide treatment
Hydraulic fitting after black oxide treatment with matte black finish

← Drag to compare raw vs. finished surface →

Black Oxide

Chemical Blackening Process

Salt Spray 24-48 hrs (+ oil)
Layer Type Fe₃O₄ Conversion
Dim. Change ~0 µm (neutral)
Appearance Matte Black
Add-On Oil Topcoat Required

Ideal Applications

Precision Fittings Low-Glare Optical Tight-Tolerance Parts Aesthetic Finish
After -- Oil Before -- Raw Raw machined hydraulic fitting before anti-rust oil treatment
Hydraulic fitting after anti-rust oil application

← Drag to compare raw vs. finished surface →

Anti-Rust Oil

Storage & Transit Protection

Protection Temporary
Film Type Petroleum Inhibitor
Dim. Change ~0 µm (neutral)
Renewable Yes, Re-applicable
Use Case Pre-install / Warehouse

Ideal Applications

Warehouse Storage Transit Protection MRO Stock Short-Term Field

Certifications &
Test Reports

All surface treatments are independently tested. Third-party SGS reports and internal quality records available for OEM qualification and sourcing audits.

ISO 9001 Quality Mgmt.
CE Mark EU Compliance
TUV Safety Certified
SGS Test Reports
RoHS Hazard-Free
REACH EU Chemical
SGS Test Report Downloads
ASTM B117 | ISO 9227

CR3+ Zinc Plating -- Salt Spray Test

SGS Report No. LF-ZN-2024-001 · ASTM B117 · 96+ Hour Certification

PDF · 2.1 MB 2024 Edition
Download Report

Zinc-Nickel Alloy -- Salt Spray Test

SGS Report No. LF-ZNNI-2024-002 · ASTM B117 · 700+ Hour Certification

PDF · 2.4 MB 2024 Edition Premium Grade
Download Report

Black Oxide -- Corrosion Resistance Test

SGS Report No. LF-BK-2024-003 · ISO 9227 · Dimensional Stability Verified

PDF · 1.8 MB 2024 Edition
Download Report

Comprehensive Surface Treatment Report

All 4 treatments · Full material traceability · Batch QC records · OEM qualification package

PDF · 5.6 MB Includes CE + TUV OEM Package
Download Package
Engineering Consultation

Not Sure Which
Treatment to Choose?

Our surface engineering team will analyze your operating environment, pressure requirements, and corrosion exposure -- then recommend the optimal treatment specification for your application.

Free Assessment

No obligation technical review of your corrosion requirements

48-Hour Response

Detailed specification recommendation within 2 business days

Sample + Report

Physical sample + SGS test data for your engineering approval

// Quick Consultation Request

Or email directly: [email protected]

ISO 9001 Certified SGS Tested Reports 20+ Years OEM Experience 14-Month Warranty