1. Material Composition & Forging Process (GNEE 7075-T6 Forged Pipes)
Alloy Chemical Composition
| Element |
Content Range |
Function |
| Zinc (Zn) |
5.1–6.1% |
Primary strengthening element |
| Magnesium (Mg) |
2.1–2.9% |
Forms MgZn₂ strengthening precipitates |
| Copper (Cu) |
1.2–2.0% |
Improves stress corrosion performance |
| Aluminum (Al) |
≥88.0% |
Base material |
| Chromium (Cr) |
0.18–0.40% |
Grain refinement |
| Iron (Fe) |
≤0.50% |
Impurity control |
| Silicon (Si) |
≤0.40% |
Impurity control |
Forging Process Parameters
| Item |
Specification |
| Preform Heating |
370–420°C |
| Forging Temperature |
340–380°C |
| Reduction Ratio |
≥4:1 to 6:1 |
| Grain Flow Direction |
Longitudinal (±10°) |
| Press Capacity |
10,000–50,000 tons |
| Strain Rate |
0.5–5 s⁻¹ |
Quality Verification:
NADCAP AC7101 third-party validation confirms elemental deviation ≤3%. Fully compliant with MIL-F-7216 (aerospace) and ISO 6363-2 precision tube standards. Supplied by GNEE, a Chinese manufacturer specializing in high-strength forged aluminum products.
2. Mechanical Strength Performance Comparison
| Property |
Forged 7075-T6 Pipe |
Standard Extrusion |
Test Standard |
| Ultimate Tensile Strength |
560–580 MPa |
525–550 MPa |
ASTM E8/E21 |
| Yield Strength (Rp0.2) |
490–510 MPa |
460–480 MPa |
ASTM E8/E21 |
| Elongation |
8–12% |
5–9% |
ASTM E8/E21 |
| Fracture Toughness |
36 MPa√m |
28–32 MPa√m |
ASTM E399 |
| Shear Strength |
325 MPa |
300 MPa |
ASTM B769 |
| Fatigue Strength (10⁷ cycles) |
160–180 MPa |
140–155 MPa |
ISO 1099 |
| Stress Rupture (100 h at 150°C) |
260 MPa |
220 MPa |
ASTM E139 |
| Compression Strength |
540 MPa |
500 MPa |
ASTM E9 |
Performance Advantage:
Directional grain structure provides 12–15% higher transverse strength and improved fatigue durability under cyclic loading.
3. Heat Treatment Process (T6 – Forged Components)
Heat Treatment Sequence
| Stage |
Parameters |
| Solution Treatment |
465–485°C (±5°C), 2–3 hours |
| Atmosphere Control |
Argon gas protection |
| Quenching |
30% PAG solution |
| Cooling Rate |
>200°C/sec (core) |
| Quench Agitation |
1.0–1.5 m/s |
| Stress Relief |
Cryogenic treatment at −70°C (2 h) |
| Artificial Aging |
120–125°C × 24 h + 165–170°C × h |
Microstructural Characteristics
| Feature |
Value |
| Grain Size |
ASTM 7–8 (15–30 μm) |
| η′ Precipitate Density |
~10¹⁷/m³ |
| Texture Intensity |
4.5–5.5 random |
| Inclusion Rating |
A0.5 / B0.5 (ASTM E45) |
| Recrystallization |
<10% |
4. Dimensions & Customization Capability
Standard & Precision Dimensions
| Parameter |
Standard Range |
Precision Grade |
Custom Capability |
| Outer Diameter |
25–600 mm |
±0.05% |
Oval/Hex |
| Wall Thickness |
3–50 mm |
±5% |
Tapered walls |
| Length |
1–12 m |
+0 / −1.5 mm |
Up to 20 m |
| Straightness |
- |
0.25 mm/m |
±0.1 mm/m |
| Wall Concentricity |
≤0.5% TIR |
≤0.2% |
≤0.1% |
| Surface Roughness |
Ra 1.6 μm |
Ra 0.4 μm |
Mirror finish |
Advanced Manufacturing Technologies (GNEE)
| Process |
Application |
| Radial Forging |
Seamless diameter reduction |
| Rotary Piercing |
Hollow billet production |
| Mandrel Forging |
Thin-wall pipes |
| Isothermal Forging |
Complex cross-sections |
| Flow Forming |
High-precision bores |
| Pilger Milling |
Nuclear-grade tubes |
5. Corrosion Resistance Performance
Environmental Resistance Ratings
| Environment |
Performance |
Corrosion Rate |
Protection |
| Marine Atmosphere |
Fair |
25–40 μm/year |
HVOF WC-17Co |
| Industrial SO₂ |
Poor |
100–150 μm/year |
Ni-Cd plating |
| Stress Corrosion |
Moderate |
SCC ≥150 MPa |
Shot peening and anodizing |
| Alclad 7075 |
Excellent |
<1 μm/year |
5% cladding |
| Forged vs Wrought |
+30% SCC resistance |
- |
Optimized grain boundaries |
Surface Protection Technologies
| Method |
Specification |
| PEO Coating |
50–100 μm, >1500 HV |
| IVD Aluminum |
20–50 μm, >3000 h salt spray |
| Electroless Nickel |
Ni-P 9–12%, 25–75 μm |
6. Machinability Characteristics
Recommended Machining Parameters
| Operation |
Tooling |
Speed (m/min) |
Feed (mm/rev) |
Notes |
| Turning |
PCD inserts |
800–1200 |
0.1–0.25 |
Positive rake |
| Drilling |
TiAlN carbide |
50–80 |
0.03–0.08 |
135° point |
| Milling |
SiAlN ceramic |
400–600 |
0.05–0.12 |
Trochoidal |
| Threading |
TiCN taps |
10–15 |
Pitch matched |
75% depth |
| Boring |
CBN tools |
200–350 |
0.04–0.10 |
Damped bars |
Machining Performance Summary
| Item |
Result |
| Machinability Index |
50% (6061-T6 = 100%) |
| Tool Life |
+200% with cryogenic cooling |
| Surface Finish |
Ra 0.2 μm achievable |
| Chatter Resistance |
+40% vs extrusions |
| Residual Stress Control |
120°C stabilization |
| Chip Formation |
Segmented chips |
Contact now
7. Weldability & Joining Methods
| Method |
Parameters / Notes |
| Friction Welding |
Preferred (HAZ-sensitive alloy) |
| Inertia Welding RPM |
2500–5000 |
| Axial Pressure |
250–400 MPa |
| Upset Force |
400–700 MPa |
| Titanium Joining |
ER4043 filler |
| Steel Joining |
Explosive transition joints |
| Adhesive Bonding |
Epoxy-novolac, 45 MPa shear |
| Mechanical Fasteners |
Hi-Lok, lock bolts |
| Diffusion Bonding |
510–530°C, 10–15 MPa |
8. Physical Properties
| Property |
Value |
Standard |
| Density |
2.81 g/cm³ |
ASTM B311 |
| Thermal Conductivity |
130 W/m·K |
ASTM E1461 |
| CTE |
23.6 μm/m·°C |
ASTM E228 |
| Electrical Conductivity |
33% IACS |
ASTM B193 |
| Elastic Modulus |
71.0 GPa |
ASTM E111 |
| Specific Heat |
1050 J/kg·K |
ASTM E1269 |
| Thermal Diffusivity |
55 mm²/s |
ASTM E1461 |
| Solidus Temp |
477°C |
ASTM E228 |
| Magnetic Permeability |
1.00002 |
ASTM A342 |
9. Surface Quality Standards (AMS 2772)
| Requirement |
Limit |
| Forging Laps / Cold Shuts |
Not allowed |
| Surface Discontinuities |
≤0.1 mm |
| Tool Marks |
≤0.01 mm |
| Heat Tint |
ΔE 1.0 |
Inspection & Finishing
| Process |
Capability |
| Chemical Milling |
0.05–0.5 mm removal |
| Electropolishing |
20–100 μm |
| Fluorescent Penetrant |
Level 3 |
| Interferometry |
0.1 μm resolution |
| Residual Stress Testing |
Barkhausen analysis |
10. Certifications, Testing & Delivery (GNEE)
Quality & Testing
| Category |
Methods |
| Chemical Analysis |
Optical emission |
| Structural Integrity |
Ultrasonic spectroscopy |
| Mechanical Testing |
Tensile, creep, Charpy |
| NDE |
PAUT, digital radiography |
| Thermal Inspection |
5 μm resolution |
Certifications
| Certification |
| AS9100 |
| NADCAP AC7117 |
| PED 2014/68/EU |
| NORSOK M650 |
| ITAR Compliance |
| ABS Marine Approval |
Applications & Delivery
| Item |
Description |
| Primary Uses |
Landing gear, missile tubes, racing suspension, helicopter shafts, hydraulic cylinders |
| Packaging |
Vacuum-sealed, desiccant protection |
| Lead Time |
12–16 weeks |
