Alloy 263 Physical Properties
- Non-magnetic. Alloy C263 plate – Nimonic 263 plate has high strength up to 1500ºF (816°C) and good oxidation resistance up to 1800ºF (982°C)
- This grade has excellent forming and welding characteristics.
- In the annealed condition, alloy CC263 nickel plate has excellent ductility and may be formed by cold working.
- Density: 0.302 lbs/in3, 8.36 g/cm3
Alloy 263 Mechanical Properties
- Hardness – Typically 200 BHN. Grain structure is austenitic at both cryogenic and elevated temperatures.
- TYPICAL STOCK REMOVAL RATE: 20 surface feet/minute with high speed tools. 80 surface feet/minute with carbide.
- Care must be taken to ensure a rigid machine setup and sharp tools, so that work hardening and surface glazing do not occur.
- Alloy C263 plate – Nimonic 263 plate has excellent welding characteristics and can be welded by most customary techniques, such as inert gas tungsten arc (TIG), gas metal arc welding (GMAW), electron beam and resistance welding. Oxyacetylene and submerged arc processes are not recommended. Avoid excessive heat input when welding and when a filler metal is required a matching C-263 filler metal should be used. This grade is typically used in the fully aged condition. Following forming and welding, a full solution anneal prior to aging is often employed to develop optimum properties.
Paduan 263 Superalloy Berbasis Nikel
NIMONIC® alloy 263 (UNS N07263/W. Nr. 2.4650), an air melted nickel-base alloy, was developed by Rolls- Royce (1971) Ltd. to provide a sheet material which could be readily fabricated and would offer improved ductility in welded assemblies to replace Paduan NIMONIK 80A. It was designed as sheet material to meet specific design criteria in terms of proof stress and creep strength.
Nimonic 263® is an age-hardenable nickel-cobalt chromium-molybdenum alloy designed specifically to combine good aged strength properties with excellent fabrication characteristics in the annealed condition. While its strength at elevated temperatures is not quite as high as Waspaloy® or Rene 41, it is far easier to form or weld than these alloys. Alloy C263 plate – Nimonic 263® plate exhibits excellent intermediate temperature tensile ductility, and is not normally subject to strain age cracking problems common for other gamma prime strengthened alloys. This grade is typically used for applications up to about 1650°F (900°C). This grade combines properties which make it suitable for a variety of fabricated components in both aircraft turbine engine and land-based turbine applications.
It is now available in all standard forms. The welding techniques for this alloy are similar to those in common use for other age-hardenable nickel- base alloys. During salvage welding operations, a pre-weld heat-treatment is not necessary on age-hardened assemblies but a subsequent age-hardening treatment is desirable after all salvage welding is completed. The material will age in service if temperatures are above 750°C.
Alloy 263 Chemical Composition:
| Elemen | Limiting Chemical Composition (%) |
|---|---|
| Karbon | 0.04%-0.08% |
| silikon | 00,40% maks |
| mangan | 0.60% max |
| Sulfur | 0.007% max |
| Perak | 0.0005% max |
| Aluminium | 0.60% max |
| Boron | 0.005% max |
| Bismuth | 0.0001% max |
| Kobalt | 19.0%-21.0% |
| kromium | 19.0%-21.0% |
| Tembaga | 0.20% max |
| Besi | 0.7% max |
| Molibdenum | 5.6%-6.1% |
| Memimpin | 0.0020% max |
| Titanium | 1.9%-2.4% |
| Aluminum and titanium | 2.4%-2.8% |
| Nikel | Balance* |
Alloy 263 Fabrication and Working Instructions:
Nimonic 263 can be hot worked in the temperature range of 1742-2102°F (950-1150°C). Cold forming mechanical properties, on the other hand, are given in the following table:
| 0.1% proof stress | 343 MPa |
|---|---|
| 0.2% proof stress | 355 MPa |
| 0.5% proof stress | 369 MPa |
| Daya tarik | 788 MPa |
| Perpanjangan pada 50 mm, % | 59.7 |
| Kekerasan | 195HV |
| Berarti ukuran butir | ASTM 6.5 |
| nilai Erichsen | 12,8mm |
| Kekuatan geser | 588MPa |
| Rasio geser terhadap kekuatan tarik | 00,75 |
Perlu diketahui bahwa data diperoleh dengan menggunakan lembaran anil setebal 0,5-1,2 mm, menggunakan teknik anil 3 menit pada suhu 1190°C dengan metode fluidized bed quenching.
Annealing Nimonic 263 diperlukan selama manipulasi dengan paduan. Petunjuk berikut harus diikuti mengenai bentuk atau bentuk:
- Batangan atau bagian yang berat biasanya dilunakkan dengan perlakuan panas yang berlangsung selama dua jam pada suhu 2102°F (1150°C);
- Annealing lembaran harus berlangsung selama 15 menit pada kisaran suhu 1922-2012°F (1050-1100°C), diikuti dengan pendinginan cepat. Untuk lembaran, pendinginan unggun terfluidisasi juga dapat digunakan.
Depending on the joint configuration and material thickness, Nimonic alloy 263 can be readily welded by argon shielded automatic and manual T.I.G and M.I.G processes. For all argon shielded welding processes the filler metal is the AMS 5966 specification (Nimonic filler metal 263). In the few next bulleted points, you can see all the different argon shielded welding processes:
- Automatic T.I.G. welding can be employed on parts with a thickness of up to 3.25 mm, and only for simple butt joints without any special shaping. The Nimonic filler metal 263 should be used for parts thicker than 1.6 mm, while welding can be obtained without filler metal for parts that are thinner than 1.6 mm;
- Panduan T.I.G. pengelasan harus dilakukan pada sambungan yang lebih rumit dengan bentuk khusus dan direkomendasikan untuk digunakan pada ketebalan hingga 4,8 mm;
- AKU G. pengelasan dapat digunakan pada semua ketebalan bagian, tetapi paling baik digunakan pada ketebalan di atas 4,8 mm. Selain itu, ini harus digunakan dibandingkan T.I.G. jika banyak pengelasan diperlukan. Kondisi transfer semprot dan celup dapat digunakan dalam proses ini.
Proses pengelasan dan penyambungan lainnya yang dapat digunakan pada paduan Nimonic 263, tetapi pada tingkat yang lebih rendah:
- Pengelasan titik, jahitan dan jahitan;
- Pengelasan flash-butt digunakan untuk pembuatan cincin turbin gas.
Alloy 263 Physical Properties:
| Kepadatan | 00,302 pon/inci3 |
|---|---|
| 8,36 gram/cm3 | |
| Rentang lebur | Suhu cairan 2471°F (1355°C) |
| Suhu solidus 2372°F (1300°C) | |
| Specific Heat at J/kg | 862°F (461°C) |
Nimonic 263 Mechanical Properties:
| Tensile strength (precipitation hardened at room temperature) | 940 MPa |
|---|---|
| 136,000 psi | |
| Kekuatan hasil (@regangan 0,200%, pengerasan presipitasi, nilai pada suhu kamar) | 550MPa |
| 79,800 psi | |
| Perpanjangan putus (presipitasi mengeras) | 39% |
Nimonic 263 Thermal Properties:
| Thermal expansion coefficient at 69.8-212°F (21-100°C) | 5,72 inci/inci°F |
|---|---|
| 10,3 m/m°C | |
| Konduktivitas termal | 81,2 BTU dalam/jam.ft².°F |
| 11,7 W/mK |
Alloy 263 Heat Treatment:
Typically, Nimonic alloy 263 should be given a two-stage heat-treatment carried out in the air, or more specifically solution treatment and age hardening. Here are all the details on recommended heat treatments for different forms of the alloy:
- Extruded or forged bars and a section for forging and /or machining – 1.5-2.5h at 2102°F (1150°C)/WQ for solution treatment and 8 h at 1472°F (800°C)/AC for aging treatment;
- Lembaran canai panas – 1,5 jam pada 2102°F (1150°C)/WQ untuk perlakuan larutan dan 8 jam pada 1472°F (800°C)/AC untuk perlakuan penuaan;
- Lembaran canai dingin dan bagian yang ditarik dingin (termasuk tabung) – 3-10 menit pada 2102°F (1150°C)/FBQ atau WQ untuk perlakuan larutan dan 8 jam pada 1472°F (800°C)/AC untuk perlakuan penuaan.
