PA66 (Nylon 66) Material Guide

Overview

PA66 (Polyamide 66, Nylon 66) is a high-performance engineering thermoplastic renowned for its excellent strength, stiffness, wear resistance, heat resistance, fatigue resistance, and dimensional stability.

Compared with PA6, PA66 offers higher mechanical strength, improved rigidity, better heat resistance, and superior long-term load-bearing performance. These characteristics make PA66 one of the most widely used engineering plastics for demanding industrial and automotive applications.

PA66 is widely used in:

  • Automotive Engine Components
  • Gears and Bearings
  • Electrical Connectors
  • Industrial Machinery Parts
  • Structural Components
  • Cable Ties
  • Power Tool Components
  • Mechanical Assemblies

Due to its excellent balance of strength, durability, and cost-effectiveness, PA66 remains one of the most important engineering thermoplastics worldwide.


Material Specification

PropertyValue
Material DesignationPA66
Full NamePolyamide 66
Common NameNylon 66
Material FamilyEngineering Thermoplastic
Density1.13–1.15 g/cm³
AppearanceNatural, Black, Colored
Typical Manufacturing MethodsInjection Molding, CNC Machining, Extrusion
Standard FormsRod, Sheet, Tube, Pellets

Chemical Composition

PA66 is produced through condensation polymerization of hexamethylenediamine and adipic acid.

ComponentFunction
Polyamide 66 PolymerStructural Matrix
StabilizersThermal Stability
Lubricants (Optional)Wear Resistance
Reinforcements (Optional)Strength Enhancement

Specialty grades may include glass fiber, mineral, or lubricant additives.


Mechanical Properties

Dry Condition

PropertyValue
Tensile Strength80–95 MPa
Yield Strength75–90 MPa
Elongation at Break20–60%
Flexural Strength110–140 MPa
Flexural Modulus2.8–3.5 GPa
HardnessRockwell R115–120
Izod Impact Strength60–120 J/m

Typical Mechanical Performance

PropertyPerformance
StrengthExcellent
StiffnessExcellent
Wear ResistanceExcellent
Fatigue ResistanceExcellent

PA66 generally provides higher strength and stiffness than PA6.


Physical Properties

PropertyValue
Density1.13–1.15 g/cm³
Water Absorption (24h)1.0–2.0%
Saturated Water Absorption6–8%
Thermal Conductivity0.25–0.30 W/m·K
Electrical Resistivity>10¹² Ω·cm
Specific Heat Capacity1700 J/kg·K

Thermal Properties

PropertyValue
Melting Point255–265°C
Heat Deflection Temperature75–110°C
Glass Transition Temperature50°C
Continuous Service Temperature-40°C to 120°C
Short-Term Service TemperatureUp to 180°C

PA66 offers better thermal performance than PA6, making it suitable for under-hood automotive applications.


Strength-to-Weight Ratio

MaterialDensity (g/cm³)Tensile Strength
PA661.1490 MPa
PA61.1480 MPa
POM1.4170 MPa
Aluminum 60612.70310 MPa

PA66 provides one of the highest strength-to-weight ratios among standard engineering plastics.


Wear Resistance

PropertyPerformance
Abrasion ResistanceExcellent
Sliding Wear ResistanceExcellent
Bearing PerformanceExcellent
Surface DurabilityExcellent

PA66 is commonly used in high-wear mechanical applications.


Friction Properties

PropertyValue
Coefficient of Friction0.20–0.40
Self-LubricatingYes
Dry Running CapabilityGood
Noise ReductionExcellent

These characteristics make PA66 suitable for gears, guides, rollers, and bushings.


Chemical Resistance

Chemical EnvironmentPerformance
Oils & GreasesExcellent
FuelsExcellent
HydrocarbonsGood
AlcoholsGood
AlkalisGood
Strong AcidsPoor
Oxidizing AgentsPoor

PA66 performs exceptionally well in automotive and industrial fluid environments.


Moisture Absorption

PropertyPerformance
Moisture AbsorptionModerate
Dimensional StabilityBetter than PA6
Strength RetentionExcellent
Environmental SensitivityModerate

Although PA66 absorbs moisture, it generally exhibits better dimensional stability than PA6.


Electrical Properties

PropertyValue
Volume Resistivity>10¹² Ω·cm
Surface Resistivity>10¹¹ Ω
Dielectric Strength15–25 kV/mm
Dielectric Constant3.5–4.0

PA66 is widely used in electrical and electronic applications.


Machinability

ProcessRating
CNC MillingExcellent
CNC TurningExcellent
DrillingExcellent
TappingExcellent
RoutingExcellent

Machinability Comparison

MaterialMachinability
PA66Excellent
PA6Excellent
POMExcellent
PolycarbonateGood

PA66 can be machined into precise, durable engineering components.


Injection Molding Characteristics

PropertyRating
MoldabilityExcellent
Flow CharacteristicsGood
Production EfficiencyExcellent
Cycle TimeFast
Surface FinishGood

PA66 is widely used in high-volume precision injection molding.


International Equivalent Grades

StandardEquivalent Grade
ISOPA66
ASTMNylon 66
DINPA66
JISNylon 66
GB/T (China)PA66 / 尼龙66
ULPolyamide 66

Available Forms

Product TypeAvailability
RodYes
SheetYes
TubeYes
PelletsYes
Injection Molded PartsYes
Machined ComponentsYes

Typical Applications

Automotive Industry

  • Engine Covers
  • Intake Manifolds
  • Radiator Components
  • Cable Ties
  • Structural Brackets

Industrial Machinery

  • Gears
  • Bearings
  • Rollers
  • Bushings
  • Wear Pads

Electrical Industry

  • Connectors
  • Terminal Blocks
  • Switch Components
  • Circuit Breaker Parts

Power Tools

  • Gear Housings
  • Structural Components
  • Mechanical Supports

Consumer Products

  • Fasteners
  • Appliance Components
  • Sporting Equipment

Medical Equipment

  • Structural Components
  • Mechanical Assemblies
  • Equipment Housings

Manufacturing Characteristics

Manufacturing ProcessRating
Injection MoldingOutstanding
CNC MachiningExcellent
ExtrusionExcellent
WeldingGood

Advantages

High Strength

Stronger than many standard engineering plastics.

Excellent Heat Resistance

Suitable for elevated-temperature environments.

Outstanding Wear Resistance

Ideal for moving mechanical components.

Excellent Fatigue Resistance

Performs well under repeated loading.

Good Chemical Resistance

Resistant to oils, greases, and fuels.

Cost Effective

Provides high performance at a reasonable cost.


Limitations

Moisture Absorption

Can affect dimensions and mechanical properties.

UV Sensitivity

Outdoor applications may require stabilization.

Acid Sensitivity

Strong acids can attack the material.

Lower Impact Resistance Than PA6

PA66 is stiffer but slightly less tough than PA6.


Comparison with Common Engineering Plastics

PropertyPA66PA6POMPC
StrengthExcellentGoodGoodGood
StiffnessExcellentGoodExcellentGood
Wear ResistanceExcellentExcellentExcellentGood
Heat ResistanceBetterGoodGoodExcellent
Impact ResistanceGoodBetterModerateExcellent

Comparison with PA6

PropertyPA66PA6
StrengthHigherLower
StiffnessHigherLower
Heat ResistanceBetterGood
Wear ResistanceSlightly BetterExcellent
Impact ResistanceGoodBetter
MoldabilityGoodBetter

Available Surface Finishes

Standard Finishes

  • Natural Finish
  • Black Finish
  • Molded Finish

Functional Finishes

  • CNC Machined Finish
  • Ground Finish
  • Polished Finish

Specialty Grades

  • Glass Filled PA66
  • Flame Retardant PA66
  • Oil Filled PA66
  • Heat Stabilized PA66

Frequently Asked Questions (FAQ)

What is PA66?

PA66 (Nylon 66) is a high-strength engineering thermoplastic known for excellent wear resistance, heat resistance, and durability.

What is PA66 used for?

Typical applications include:

  • Gears
  • Bearings
  • Automotive Parts
  • Electrical Connectors
  • Industrial Machinery Components

Is PA66 stronger than PA6?

Yes. PA66 generally offers higher strength, stiffness, and heat resistance.

What is the difference between PA66 and PA6?

PA66 provides better mechanical and thermal performance, while PA6 offers greater toughness and easier processing.

Is PA66 self-lubricating?

Yes. PA66 exhibits low friction and excellent wear characteristics.

Can PA66 be machined?

Yes. PA66 offers excellent CNC machining performance.

Why choose PA66?

Because it combines:

  • High Strength
  • Excellent Wear Resistance
  • Good Heat Resistance
  • Low Friction
  • Long Service Life

What is the biggest disadvantage of PA66?

Moisture absorption can influence dimensions and stiffness.

Does GCNOV provide PA66 manufacturing services?

Yes. GCNOV provides:

  • PA66 CNC Machining
  • PA66 Injection Molding
  • Custom Plastic Fabrication
  • Prototype Development
  • Surface Finishing
  • Low-Volume Production
  • Mass Production
  • Industrial Component Manufacturing