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1 INCOLOY alloy alloy 825 (UNS N08825 ) is anickel-iron-chromium alloy with additions ofmolybdenum, copper, and titanium. The alloy schemical composition, given in Table 1, is designed toprovide exceptional resistance to many corrosiveenvironments. The nickel content is sufficient forresistance to chloride-ion stress-corrosion cracking. Thenickel, in conjunction with the molybdenum andcopper, also gives outstanding resistance to reducingenvironments such as those containing sulfuric andphosphoric acids.

2 The molybdenum also aids resistanceto pitting and crevice corrosion. The alloy s chromiumcontent confers resistance to a variety of oxidizingsubstances such as nitric acid, nitrates and oxidizingsalt. The titanium addition serves, with an appropriateheat treatment, to stabilize the alloy againstsensitization to intergranular resistance of INCOLOY alloy 825 to generaland localized corrosion under diverse conditions givesthe alloy broad usefulness. Applications includechemical processing, pollution control, oil and gasrecovery, acid production, pickling operations, nuclearfuel reprocessing, and handling of radioactive for alloy 825 are similar to those forINCOLOY alloy 11- Limiting Chemical Composition, % of INCOLOY alloy 825 Nickel.

3 CCoonnssttaannttss aanndd TThheerrmmaallPPrrooppeerrttiieessSome physical constants for INCOLOY alloy 825 arelisted in Table 2. Values for thermal expansion, thermalconductivity, and electrical resistivity at varioustemperatures are in Table 3. Modulus of elasticity andPoisson s ratio over a range of temperatures are given inTable 4. Modulus values, which were determineddynamically, were used to compute Poisson s 22- Physical ConstantsDensity, Range, F ..2500-2550 C ..1370-1400 Specific Heat, Btu/lb F.

4 C ..440 Curie Temperature, F ..<-320 C ..<-196 Permeability at 200 oersted ( kA/m) .. 33- Thermal PropertiesTTeemmppeerraattuurreeEElleecc ttrriiccaallRReessiissttiivviittyyTThhee rrmmaallCCoonndduuccttiivviittyyCCooeeff ffiicciieenntt ooffEExxppaannssiioonnaaoohhmm cciirrcc mmiill//ffttBBttuu--iinn//fftt22 hh FF1100--66iinn//iinn FF 793 mmWW//mm CC mm//mm CC coefficient of linear expansion between 80 F (27 C) andtemperature data contained in this publication is for informational purposes only andmay be revised at any time without prior notice.

5 The data is believed to beaccurate and reliable, but Special Metals makes no representation or warranty ofany kind (express or implied) and assumes no liability with respect to theaccuracy or completeness of the information contained herein. Although thedata is believed to be representative of the product, the actual characteristics orperformance of the product may vary from what is shown in this contained in this publication should be construed as guaranteeing theproduct for a particular use or Number SMC-030 Copyright Special Metals Corporation, 2004 (Sept 04)

6 INCOLOY, INCONEL, INCO-WELD and 686 CPT aretrademarks of the Special Metals Corporation group aallllooyy 8822552 TTeemmppeerraattuurreePPooiissssoonn ssRRaattiiooSShheeaarrMMoodduulluussYYoo uunngg ssMMoodduulluussGGPPaaGGPPaa CCTT eemmppeerraattuurreePPooiissssoonn ssRRaattiiooSShheeaarrMMoodduulluussYYoo uunngg ssMMoodduulluuss110033kkssii110033kkssii PPrrooppeerrttiieessINCOLOY alloy 825 has good mechanical properties from cryogenic temperatures to moderately high temperatures. Exposureto temperatures above about 1000 F (540 C) can result in microstructural changes (phase formation) that significantly lowerductility and impact strength.

7 For that reason, the alloy is not normally used at temperatures where creep-rupture propertiesare design properties at room temperature are listed in Table 5. As indicated, the alloy can be strengthened substantially bycold tensile properties are shown in Figure 1. The tests were conducted on cold-drawn rod of (19-mm) diameter annealed at 1725 F (940 C)/1 yield strength of the alloy is similar to tensile yield strength. Tests on annealed rod of (25-mm)diameter produced a compressive yield strength ( offset) of 61,400 psi (423 MPa) compared with a tensile yield strengthof 57,500 psi (396 MPa).

8 Ultimate tensile strength of the material was 104,500 psi (720 MPa).INCOLOY alloy 825 has good impact strength at room temperature and retains its strength at cryogenic 6 gives the results of Charpy keyhole tests on 55- Typical Room-Temperature Tensile PropertiesTubing, Annealed1127726444136 Tubing, Cold Drawn145100012988915 Bar, Annealed1006904732445 Plate, Annealed966624933845 Sheet, Annealed1107586142139 FFoorrmm aannddCCoonnddiittiioonnEElloonnggaattii oonn,,%%kkssiikkssiiMMPPaaMMPPaaTTeennss iillee SSttrreennggtthhYYiieelldd SSttrreennggtthh(( OOffffsseett))

9 FFiigguurree tensile properties of annealed the typical usage , ksi Elongation, %Temperature, FTemperature, CStress, MPaTTaabbllee 44- Modulus of Elasticity (Hot Rolled and Annealed Plate)Tensile StrengthElongationYield Strength( Offset)OOrriieennttaattiioonn FF CCfftt--llbbJJTT eemmppeerraattuurreeIImmppaacctt SSttrreennggtthhaaTTaabbllee 66- Charpy Keyhole Impact Strength of of three aallllooyy 8822553 CCoorrrroossiioonn RReessiissttaanncceeThe outstanding attribute of INCOLOY alloy 825 is its high level of corrosion resistance.

10 In both reducing and oxidizeenvironments, the alloy resists general corrosion, pitting, crevice corrosion, intergranular corrosion, and stress-corrosioncracking. Some environments in which INCOLOY alloy 825 is particularly useful are sulfuric acid, phosphoric acid, sulfur-containing flue gases, sour gas and oil wells, and sea details on the corrosion resistance of alloy 825 , refer to Special Metals publication Restistance to AqueousCorrosion , on the website, standard machining operations are readily performed onINCOLOY alloy 825 .