Aluminum 5083-H116
Introduction to Aluminum 5083-H116
Aluminum 5083-H116 is a strain-hardened, non-heat-treatable aluminum-magnesium alloy specifically processed for enhanced corrosion resistance in marine and saltwater environments. The H116 temper designates that the alloy has been strain-hardened and stabilized for improved strength, weldability, and resistance to exfoliation and stress corrosion.
Aluminum 5083-H116 is widely used in CNC machining of marine structures, offshore equipment, transportation panels, and defense components that demand rugged strength, excellent weld performance, and long-term corrosion stability.
Chemical, Physical, and Mechanical Properties of Aluminum 5083-H116
Chemical Composition (Typical)
Element | Composition Range (wt.%) | Key Role |
|---|---|---|
Aluminum (Al) | Balance | Base metal for corrosion resistance |
Magnesium (Mg) | 4.0–4.9 | Major strengthening element, improves seawater resistance |
Manganese (Mn) | 0.4–1.0 | Enhances strength and toughness |
Chromium (Cr) | 0.05–0.25 | Increases corrosion resistance in marine environments |
Silicon (Si) | ≤0.40 | Residual element |
Iron (Fe) | ≤0.40 | Residual element |
Copper (Cu) | ≤0.10 | Residual element |
Zinc (Zn) | ≤0.25 | Residual element |
Physical Properties
Property | Value (Typical) | Test Standard/Condition |
|---|---|---|
Density | 2.66 g/cm³ | ASTM B311 |
Melting Point | 570–640°C | ASTM E299 |
Thermal Conductivity | 121 W/m·K at 25°C | ASTM E1952 |
Electrical Conductivity | 32% IACS at 20°C | ASTM B193 |
Coefficient of Expansion | 25.3 µm/m·°C | ASTM E228 |
Specific Heat Capacity | 900 J/kg·K | ASTM E1269 |
Elastic Modulus | 70 GPa | ASTM E111 |
Mechanical Properties (H116 Temper)
Property | Value (Typical) | Test Standard |
|---|---|---|
Tensile Strength | 310–350 MPa | ASTM E8/E8M |
Yield Strength (0.2%) | 230–280 MPa | ASTM E8/E8M |
Elongation | ≥10% | ASTM E8/E8M |
Hardness | 85–95 HB | ASTM E10 |
Fatigue Strength | 110–130 MPa | ASTM E466 |
Impact Resistance | Excellent | ASTM E23 |
Key Characteristics of Aluminum 5083-H116
Marine-Grade Corrosion Resistance: Specially treated for superior performance in saltwater and brine environments. Resists pitting, stress corrosion, and exfoliation corrosion.
Enhanced Strength in Stabilized Temper: Offers higher yield strength than 5083-O or H321 while maintaining ductility and formability—ideal for thick-plate marine components and structural frames.
Excellent Weldability Without Post-Weld Cracking: Weld joints retain over 90% of base material strength, especially when using 5356 filler wire for MIG/TIG processes.
Good Dimensional Stability: H116 temper prevents warping during CNC machining, particularly on large flat panels or structural parts.
Non-Heat Treatable Alloy: Mechanical strength is increased through strain hardening, not thermal processing. Properties remain stable even in prolonged service.
CNC Machining Challenges and Solutions for Aluminum 5083-H116
Machining Challenges
Work Hardening: Aggressive passes or poor chip removal can cause excessive tool wear.
Built-Up Edge (BUE): Material adhesion may reduce surface quality and tool life.
Large Component Size: Often used in large-format plates requiring fixture precision and high-torque CNC setups.
Optimized Machining Strategies
Tool Selection
Parameter | Recommendation | Rationale |
|---|---|---|
Tool Material | TiAlN-coated or diamond-polished carbide | Reduces friction and resists galling |
Geometry | Large rake with high-precision flute | Promotes chip flow and surface integrity |
Cutting Speed | 200–350 m/min | Balances temperature and tool life |
Feed Rate | 0.10–0.25 mm/rev | Maintains tight tolerance and avoids chatter |
Coolant | Flood or high-mist (≥30 bar) | Removes heat and minimizes tool adhesion |
Aluminum 5083-H116 Cutting Parameters (ISO 513 Compliance)
Operation | Speed (m/min) | Feed (mm/rev) | Depth of Cut (mm) | Coolant Pressure (bar) |
|---|---|---|---|---|
Roughing | 200–280 | 0.15–0.25 | 2.0–4.0 | 30–40 (Flood) |
Finishing | 280–350 | 0.05–0.10 | 0.2–1.0 | 40–60 (Flood/Mist) |
Surface Treatment for Aluminum 5083-H116 CNC Parts
Anodizing: Compatible with both Type II and hard anodizing; adds up to 50 µm of protection for marine parts.
Powder Coating: Achieves >1000 hours of salt spray resistance (ASTM B117) with 60–100 µm of coating thickness.
Electropolishing: Enhances corrosion resistance on complex geometries and internal channels.
Passivation: Ensures clean surfaces for pre-coating or bare service parts.
Brushing: Creates Ra 1.0–1.6 µm finishes ideal for anti-glare marine or structural panels.
Alodine Coating: Enhances corrosion resistance without impairing electrical continuity. It is useful in electrical enclosures and terminals.
UV Coating: Adds scratch resistance and long-term clarity for exposed surfaces.
Lacquer Coating: Prevents oxidation and enhances aesthetics in high-end defense and marine parts.
Industry Applications of Aluminum 5083-H116
Marine: Ship hulls, offshore platforms, and underwater housings requiring structural strength and saltwater corrosion resistance.
Defense: Armor plate, radar mounts, and support frames used in naval and tactical environments.
Oil & Gas: Pipe flanges, riser clamps, and sub-sea components exposed to aggressive media.
Automotive (Special Vehicles): Tanker trailers, armored vehicles, and battery enclosures where weight and corrosion resistance are critical.
Industrial Equipment: CNC-machined load-bearing brackets, conveyors, and process housings exposed to corrosive industrial atmospheres.
FAQs
How does Aluminum 5083-H116 differ from 5083-O or H321 in corrosion resistance?
Can Aluminum 5083-H116 be TIG welded without post-weld heat treatment?
What are typical machining tolerances and surface finishes achievable in CNC 5083-H116 parts?
Which industries most commonly use Aluminum 5083-H116 in CNC applications?
What surface coatings are most effective for enhancing 5083-H116 performance in marine environments?
Explore Related Blogs
