What are the differences between Inconel 625 and GH4169
The main difference lies in their chemical composition and strengthening mechanisms. Inconel 625 is known for its high corrosion resistance, while GH4169 is known for its high strength and hardness. This difference stems from their different chemical compositions and strengthening mechanisms; 625 contains higher levels of chromium and molybdenum, enabling it to withstand harsh chemical environments, while GH4169 contains higher levels of niobium, titanium, and cobalt, allowing it to be strengthened through precipitation hardening.
What is GH4169?
GH4169, also known as Inconel 718, is a nickel-chromium alloy renowned for its excellent high-temperature strength, corrosion resistance, and superior mechanical properties. This high-temperature alloy is widely used in aerospace, nuclear reactors, and gas turbines, where high-performance materials are crucial.
Inconel 625 Composition
| Inconel | Element (% by mass) | ||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Ni | Cr | Fe | Mo | Nb | Co | Mn | Cu | Al | Ti | Si | C | S | P | B | |
| 625 | 58.0 | 20.0–23.0 | 5.0 | 8.0–10.0 | 3.15–4.15 | 1.0 | 0.5 | 0.4 | 0.4 | 0.5 | 0.1 | 0.015 | 0.015 | ||
Chemical composition of GH4169 alloy(%)
| Element | Composition (%) |
|---|---|
| Nickel (Ni) | 50.0 – 55.0 |
| Chromium (Cr) | 17.0 – 21.0 |
| Iron (Fe) | Balance |
| Molybdenum (Mo) | 2.8 – 3.3 |
| Niobium (Nb) + Tantalum (Ta) | 4.75 – 5.5 |
| Titanium (Ti) | 0.65 – 1.15 |
| Aluminum (Al) | 0.2 – 0.8 |
| Cobalt (Co) | ≤ 1.0 |
| Manganese (Mn) | ≤ 0.35 |
| Silicon (Si) | ≤ 0.35 |
| Sulfur (S) | ≤ 0.015 |
| Phosphorus (P) | ≤ 0.015 |
| Carbon (C) | ≤ 0.08 |
| Copper (Cu) | ≤ 0.3 |
| Boron (B) |
0.001 – 0.006 |
Comparison: Inconel 625 vs. GH4169 (Inconel 718)
| Feature | Inconel 625 (UNS N06625) | GH4169 / Inconel 718 (UNS N07718) |
|---|---|---|
| Primary Strength Mechanism | Solid solution strengthened by molybdenum and niobium additions. | Precipitation hardened, primarily by gamma double prime (γ'') precipitates formed through specific heat treatments, which relies on additions of aluminum and titanium. |
| Main Performance Focus | Superior corrosion resistance, particularly in a broad range of highly corrosive environments, including seawater and various acids. | High strength and good heat resistance up to moderate high temperatures (around 700°C or 1292°F). |
| Key Alloying Elements | Higher levels of chromium and molybdenum for enhanced corrosion resistance. | Higher amounts of titanium and aluminum compared to 625; iron makes up more of the balance. |
| Weldability | Generally known for excellent weldability and formability. | Good weldability, though specific post-weld heat treatments are often necessary for optimal properties. |
| Typical Applications | Offshore piping systems, heat exchangers, chemical processing equipment, and gas turbine ducting. | Aerospace components (discs, blades, shafts, fasteners), power generation, and parts requiring high strength at elevated temperatures. |
Summary
Essentially, Inconel 625 is primarily a corrosion-resistant, high-temperature-resistant alloy, while GH4169 (Inconel 718) is a high-strength alloy designed for applications requiring heavy loads at high temperatures. They have different uses and cannot be directly substituted for each other.
Why Choose Gnee Nickel Alloy (Supplier Example)?
✅ Large stock of GH4169 alloy tubes/bars/plates/fittings available for fast shipping.
✅ Factory direct sales, highly competitive prices, excellent value for money.
✅ Comprehensive quality assurance: Material Testing Certificate (MTC), Chemical Composition Certificate, and Mechanical Properties Certificate.
✅ Value-added services: Slitting, cutting, polishing, surface treatment.
✅ Worldwide shipping, secure and reliable packaging, and provision of export-required documents.
Email: ss@gneemetal.com
Gnee Steel is a supplier of GH4169 alloy, offering a wide range of products including: seamless pipe (sizes: 4-219 mm; thickness: 0.5-20 mm); welded pipe (sizes: 5.0-1219.2 mm; thickness: 0.5-20 mm); plates (thickness: 0.1 to 100 mm; width: 10-2500 mm); strips; alloy round bars (diameter: 3-800 mm); flat bars (thickness: 2-100 mm; width: 10-500 mm); hexagonal bars (size: 2-100 mm); wire rods; and extruded profiles. We collaborate with steel mills to provide our customers with GH4169 alloy products that meet or exceed numerous leading industry standards, including ASTM, ASME, SAE, AMS, ISO, DIN, EN, and BS standards.
Gnee Steel stocks and sells GH4169, pipes, plates, strips, round bars, flat bars, forged billets, hexagonal steel, wire rods, and extruded profiles. Please feel free to contact us at ss@gneesteel.com for a quote.
