Alloy PK33 is a vacuum-melted nickel-chromium-cobalt superalloy that employs both precipitation hardening and solid-solution strengthening through strategic molybdenum additions . Developed specifically as a sheet material with ultrahigh strength and good formability, it offers exceptional high-temperature strength, creep resistance, and weldability up to 950°C (1740°F), making it particularly suitable for gas turbine flame tubes, combustion chambers, and welded fabrications requiring thermal fatigue resistance .
1. Product Specifications & Physical DataZYTC Alloy supplies Nimonic® PK33 in comprehensive mill forms for aerospace combustion hardware, industrial furnace components, and high-temperature processing equipment requiring verified properties and complete material traceability. Available Forms: Sheet, plate, round bar, flat bar, forging stock, extruded sections, and welding wire . Specifications: DTD 5057, AFNOR NC19 KDu/v, BS HR 8, Werkstoff Nr. 2.4955, UNS N07041 .
| Chemical Composition (Weight %) | Alloy PK33 Specification |
|---|
| Nickel (Ni) | Balance | | Chromium (Cr) | 16.0 - 20.0 | | Cobalt (Co) | 12.0 - 16.0 | | Molybdenum (Mo) | 5.0 - 9.0 | | Titanium (Ti) | 1.5 - 3.0 | | Aluminum (Al) | 1.7 - 2.5 | | Iron (Fe) | 1.0 max. | | Carbon (C) | 0.07 max. | | Zirconium (Zr) | 0.06 max. | | Boron (B) | 0.005 max. |
| Physical Properties | Metric | Imperial |
|---|
| Density | 8.21 - 8.25 g/cm³ | 0.297 - 0.298 lb/in³ | | Melting Range | 1300 - 1380°C | 2370 - 2515°F | | Modulus of Elasticity (RT) | 220 GPa | 32.0 × 10⁶ psi | | Thermal Expansion (20-100°C) | 12.1 µm/m·°C | 6.7 µin/in·°F | | Thermal Conductivity (RT) | 11.3 W/m·K | 78.3 BTU·in/hr·ft²·°F |
| Mechanical Properties (Precipitation Hardened) | Condition | Metric | Imperial |
|---|
| Tensile Strength (RT) | Bar (2h/1100°C + 4h/850°C) | 1127 MPa | 163.5 ksi | | Yield Strength (0.1% offset, RT) | Same condition | 664 MPa | 96.3 ksi | | Elongation (RT) | Same condition | 33% | 33% | | Tensile Strength (RT) | Typical aged | 1150 MPa | 167 ksi | | Yield Strength (0.2% offset, RT) | Typical aged | 750 MPa | 109 ksi | | Elongation (RT) | Typical aged | 30% | 30% |
2. Fabrication & Material ComparisonNimonic® PK33 was developed specifically for sheet applications requiring both high creep strength and good formability, making it particularly suitable for complex welded fabrications . Heat Treatment : Solution Annealing (Hot-rolled sheet): 1100-1120°C × 0.5 hours, air cool or water quench Solution Annealing (Cold-rolled sheet): 1100-1120°C × 5-15 minutes, air cool, fluidized bed quench, or water quench Aging (All forms): 850°C × 4 hours, air cool Two-stage (Bar): 1100°C/2h/AC + 850°C/4h/AC
Hot Working: 980-1140°C (1796-2084°F); can be hot worked or cold worked . Cold Working: Good formability in solution-annealed condition; can be formed, deep-drawn, and spun . Heavy-duty lubricants recommended; all residues must be cleaned after forming. Welding: Excellent weldability using GTAW (TIG) and GMAW (MIG) processes; techniques similar to other nickel-base age-hardenable alloys . Matching filler metal recommended. Pre-weld cleaning essential. Machining: Work-hardens during cutting; requires heavy-duty equipment, rigid setups, and sharp tools. Water-based coolants for high-speed operations; heavy lubricants for drilling and tapping.
Applications Aerospace & Gas Turbines: Combustion chamber liners, flame tubes, afterburner components, jet pipes, reheat systems, exhaust ducting, heat shields, turbine shrouds Power Generation: Combustion chamber assemblies, transition ducts, diffusers Industrial Processing: High-temperature furnace components, radiant tubes, retorts, high-temperature containers, chemical reactor liners Special Applications: Rocket engine components, high-temperature seals and gaskets, nuclear reactor components
Contact ZYTC Alloy for certified Nimonic® PK33 materials with complete traceability, technical datasheets, and competitive pricing on standard sizes or custom-fabricated components. Email:daisy@zytcsteel.com WhatsApp/WeChat: +86 17335753350 |
