5083 aluminum alloy (ASTM B209, EN AW-5083) is a high-strength, non-heat-treatable Al-Mg alloy renowned for exceptional weldability and superior corrosion resistance in marine environments. The ultra-thick forged plate variant offers enhanced mechanical properties through controlled deformation processing:

Primary Alloying Elements:

Magnesium (Mg): 4.0-4.9% (primary solid-solution strengthener)

Manganese (Mn): 0.40-1.0% (grain structure refinement)

Chromium (Cr): 0.05-0.25% (corrosion resistance enhancement)

Titanium (Ti): 0.05-0.15% (grain refinement)

Base Material:

Aluminum (Al): ≥92.4% (balance)

Controlled Impurities:

Iron (Fe): ≤0.40% max

Silicon (Si): ≤0.40% max

Copper (Cu): ≤0.10% max

Zinc (Zn): ≤0.25% max

Specialized Ultra-Thick Forging Process:

Premium Ingot Production:

Direct Chill (DC) semi-continuous casting

Grain refinement with Ti-B additions

Melt degassing to <0.1ml H₂/100g Al

Filtration through ceramic foam filters

Homogenization Treatment:

500-520°C for 24-36 hours

Computer-controlled cooling rate

Microstructural equilibration

Surface Preparation:

Scalping of segregation layer (minimum 10mm)

Surface inspection for defects

Preheating for Forging:

Staged heating to 380-430°C

Temperature uniformity ±5°C

Multi-Directional Open-Die Forging:

Initial forging temperature: 400-425°C

Final forging temperature: 340-380°C

Deformation ratio: 3:1 to 5:1

Multi-directional working to optimize properties

Specialized dies for ultra-thick sections

Controlled Cooling:

Programmed cooling rate to minimize residual stress

Air-cooling with thermal blankets for thick sections

Stress Relief Treatment:

240-300°C for 1 hour per 25mm thickness

Furnace cooling to below 200°C

Final Processing:

Precision machining to customer specifications

Surface inspection and cleaning

Protective packaging for shipment

All manufacturing processes are performed under ISO 9001 quality management system with complete traceability.

 

Property	Minimum	Typical	Test Standard	Ultra-Thick Advantage
Ultimate Tensile Strength	290 MPa	305-330 MPa	ASTM B557	Uniform properties throughout section
Yield Strength (0.2%)	145 MPa	160-185 MPa	ASTM B557	Enhanced through-thickness strength
Elongation (50mm gauge)	12%	16-22%	ASTM B557	Superior ductility across full section
Hardness (Brinell)	85 HB	90-100 HB	ASTM E10	Consistent hardness profile
Shear Strength	175 MPa	185-200 MPa	ASTM B769	Enhanced joint reliability
Fatigue Strength (10⁸)	120 MPa	125-140 MPa	ASTM E466	Improved cyclic loading performance
Compressive Yield	145 MPa	160-190 MPa	ASTM E9	Critical for load-bearing applications
Bearing Strength (e/D=2.0)	385 MPa	400-430 MPa	ASTM E238	Superior fastener performance
Impact Energy (Charpy)	35 J	40-50 J	ASTM E23	Enhanced toughness at low temperatures

 

Through-Thickness Performance:

Property variation <5% between surface and core (up to 200mm thickness)

Directionality ratio (L:LT:ST): 1.00:0.95:0.90 for tensile strength

Core temperature maintained within critical processing window

Hardness variation <8 HB from surface to center

 

 

 

Critical Forging Parameters:

Strain Distribution Control:

Minimum total true strain: 1.1-1.3

Strain rate: 0.01-0.1 s⁻¹

Multi-directional working (minimum 25% in secondary direction)

Intermittent reheating for sections >150mm

Temperature Management:

Maximum temperature gradient: 30°C across section

Computer-controlled thermal profile monitoring

Extended dwell times for temperature homogenization

Specialized handling equipment for minimal heat loss

Microstructural Characteristics:

Grain Size: ASTM 5-7 (30-60μm)

Grain Morphology: Partially recrystallized structure

Al₆Mn dispersoid distribution: 0.1-0.5μm diameter

Mg₂Si precipitate control: <0.5 volume percent

Al-Fe-Mn intermetallic phases: Controlled morphology

Recrystallized Volume Fraction: 40-60%

Texture: Mixed deformation/recrystallization texture

Grain Aspect Ratio: 1.5:1 maximum in final product

Special Features:

Subgrain structure with high misorientation angles

Limited recovery due to Mg solute drag effect

Al₃Mg₂ precipitation controlled to prevent sensitization

Enhanced dislocation density: 5-8×10¹⁰/cm²

 

 

 

Parameter	Standard Range	Precision Tolerance	Commercial Tolerance
Thickness	150-400 mm	±3 mm	±5 mm
Width	1000-3000 mm	±5 mm	±8 mm
Length	2000-8000 mm	±7 mm	±12 mm
Flatness	N/A	0.2% of length	0.4% of length
Parallelism	N/A	0.6% of thickness	1.0% of thickness
Edge Straightness	N/A	2 mm/m	4 mm/m
Surface Roughness	N/A	6.4 μm Ra max	12.5 μm Ra max

 

Ultra-Thick Specific Parameters:

Density: 2.66 g/cm³ (±0.01)

Weight Calculation: Thickness(mm) × Width(m) × Length(m) × 2.66 = Weight(kg)

Maximum Single Plate Weight: 20,000 kg

Machining Allowance: Recommend 15mm per side minimum for critical dimensions

Stress Relief: Required before precision machining for plates >200mm

Plate Flatness: Measured under self-weight on flat surface

Ultrasonic Testing: 100% volumetric inspection available

 

Environment	Performance	Corrosion Rate	Expected Service Life
Marine Atmosphere	Excellent	<0.02 mm/year	30+ years
Immersed Seawater	Very Good	<0.10 mm/year	25+ years
Industrial Exposure	Excellent	<0.05 mm/year	25+ years
Fresh Water	Excellent	Negligible	40+ years
Stress Corrosion	Excellent	Highly resistant	Design life
Exfoliation	Excellent	EXCO rating EA	Design life
Galvanic Coupling	Fair	Isolation required	Application dependent

 

Corrosion Protection Options:

Anodizing:

Type II (Sulfuric acid): 10-25μm thickness

Type III (Hard anodize): 25-75μm thickness

Marine-grade sealing treatments

Conversion Coatings:

Chromate conversion per MIL-DTL-5541

Chrome-free alternatives for environmental compliance

Titanium/Zirconium-based treatments

Protective Systems:

Epoxy primer + polyurethane topcoat

Marine-grade multi-layer systems

Sacrificial zinc-rich primers

High-build epoxy coatings for immersion service

Environmental Performance Factors:

Sensitization Resistance: Superior to 5086 alloy

NAMLT Test Performance: <15mg/cm²

IGC Resistance: Excellent after stabilization treatment

H₂ Embrittlement: Minimal susceptibility

 

 

Operation	Tool Material	Recommended Parameters	Notes for Ultra-Thick Sections
Heavy Milling	Carbide	Vc=300-600 m/min, fz=0.15-0.30 mm	Climb milling recommended
Deep Hole Drilling	Carbide drills	Vc=60-100 m/min, fn=0.15-0.25 mm/rev	Step drilling for deep holes
Face Milling	PCD cutters	Vc=500-1000 m/min	High positive rake angles
Turning	Carbide/PCD	Vc=200-500 m/min	Rigid setup essential
Tapping	HSS-E taps	Vc=10-20 m/min	50% thread recommended
Sawing	Carbide-tipped	40-60 m/min	Flood coolant mandatory

 

Fabrication Considerations:

Forming Limits: Minimum bend radius 2.5× material thickness

Cold Working: Limited to 15-20% before annealing

Hot Working: 260-370°C optimal temperature range

Weldability: Excellent with 5183, 5356, or 5556 filler

Welding Methods: GMAW, GTAW, FCAW suitable

Post-weld Treatment: Brush/needle scaling recommended

Stress Relief After Welding: 200°C for 1 hour per 25mm

Cutting Methods: Plasma, waterjet, or sawing preferred

 

 

 

Welding Process	Filler Material	Parameters	Special Considerations
GMAW (MIG)	ER5183, ER5556	DCEP, 22-26V, 140-250A	Pulse spray transfer recommended
GTAW (TIG)	ER5183, ER5356	AC, 12-15V, 120-200A	Thoriated tungsten electrodes
FCAW	E5183T, E5556T	DCEP, 24-28V, 150-260A	Minimal interpass cleaning
SAW	ER5183, ER5356	26-30V, 350-550A	Neutral or slightly basic flux

 

Welding Best Practices for Ultra-Thick Sections:

Joint Preparation:

X-groove or double-V for thickness >25mm

Root gap 2-4mm

Root face 1-3mm

Bevel angle 50-60°

Thorough degreasing with acetone or MEK

Preheating:

Generally not required

For sections >200mm, preheat 50-80°C to reduce thermal gradient

Interpass Temperature:

Maximum 120°C

Monitor with infrared thermometer

Post-weld Treatment:

Stress relief recommended for thick sections

Thorough cleaning of flux and spatter

Inspection Methods:

Visual inspection per AWS D1.2

Radiographic or ultrasonic testing for critical joints

Dye penetrant for surface defects

 

Property	Value	Design Implications
Density	2.66 g/cm³	Weight calculations and buoyancy
Melting Range	574-638°C	Welding and heat treatment parameters
Thermal Conductivity	117 W/m·K	Heat dissipation in thermal applications
Electrical Conductivity	29% IACS	Electrical applications and design
Specific Heat Capacity	900 J/kg·K	Thermal inertia calculations
Thermal Expansion	23.8 ×10⁻⁶/K	Expansion joint design and thermal stress
Young’s Modulus	71 GPa	Structural stiffness and deflection
Poisson’s Ratio	0.33	Strain relationships in complex loading
Damping Capacity	Moderate (0.01-0.02)	Vibration control applications

 

Environmental Performance:

Operating Temperature Range: -196°C to +200°C

Cryogenic Performance: Excellent toughness retention

Fire Resistance: Non-combustible

Magnetic Properties: Non-magnetic

Radiation Resistance: Excellent

Recyclability: 100% recyclable with no quality loss

Environmental Impact: Lower energy footprint than steel

 

 

 

Standard Inspection Regime:

Chemical Composition Testing:

Optical emission spectroscopy

Verification of all alloying elements

Mechanical Testing:

Tensile testing (longitudinal and transverse directions)

Hardness mapping (surface and cross-section)

Impact testing for critical applications

Non-Destructive Testing:

Ultrasonic inspection per ASTM A578/A578M

Dye penetrant inspection for surface defects

Dimensional Inspection:

CMM verification of critical dimensions

Thickness mapping at specified grid points

Flatness measurement under self-weight

Microstructural Analysis:

Grain size determination

Inclusion rating per ASTM E45

Sensitization testing for H tempers

Metallographic examination

Certification Options:

Mill Test Report (EN 10204 3.1)

Third-party inspection certification (EN 10204 3.2)

DNV-GL certification for marine applications

ABS certification for marine structures

Lloyd’s Register certification

Customer-specific certification requirements

Material traceability documentation

Production record documentation

 

 

 

Primary Applications:

Naval and commercial shipbuilding

Offshore oil & gas platforms

Pressure vessel components

Cryogenic storage and transport

Heavy transportation structures

Bridge decking and structural components

Defense industry applications

Chemical processing equipment

Mining equipment structures

Marine propulsion system components

Specific Use Cases:

LNG Carrier Structural Components:

Superior low-temperature toughness

Excellent weldability for complex structures

Good strength-to-weight ratio