800H / UNS N08810 Heat Resistant Alloys Excellent Creep Rupture Strength

Corrosion and heat resistant alloy Alloy 800H, UNS N08810 for chemical and petrochemical processing

 

1 PRODUCT

Corrosion and heat resistant alloys Alloy 800H, UNS N08810 for chemical and petrochemical processing

 

2 EQUIVALENT DESIGNATION

INCOLOY® 800H, VDM^® Alloy 800H, W.Nr.1.4876, X10NiCrAlTi32-20(EN), 1.4958, X5NiCrAlTi31-20(EN), FeNi32Cr21AlTi-HC(ISO), 15H(NA), NS1102

 

3 PRODUCT FORM

Forging, plate, sheet, strip, tube and pipe, pipe fitting, bar, rod, wire, ring, fastener etc.

 

4 OVERVIEW

Alloy 800, 800H and 800HT series are heat and corrosion resistant alloys with a relatively low nickel content, maintaining the ultimate chemical properties for high temperature strength and resistance to oxidation, carburization and other types of high temperature corrosion, has set the industry standard in high temperature applications requiring optimum creep and rupture properties.

Alloy 800H is an austenitic, heat resistant iron- nickel -chromium alloy with controlled levels of carbon, aluminum and titanium.

The analysis of Alloy 800H is identical to that of Alloy 800. A special solution annealing results in a grain sizes ≥ 90µm (ASTM No.4), which increases the creep rupture strength above 600°C (1112°F) significantly.

Alloy 800H is characterized by:

good creep rupture strength at temperatures above 600°C (1112°F)

good resistance in oxidizing, nitriding and carburizing conditions

metallurgical stability in long-term use at high temperatures

 

5 APPLICATION

Alloy 800, 800H and 800HT are used in a variety of applications involving exposure to corrosive environments and high temperatures.

They are used for heat treating equipment such as baskets, trays, and fixtures.

In chemical and petrochemical processing, the alloys are used for heat exchangers and other piping systems in nitric acid media especially where resistance to chloride stress-corrosion cracking is required.

In nuclear power plants, they are used for steam-generator tubing. The alloys are often used in domestic appliances for sheathing of electric heating elements.

In petroleum processing, the alloys are used for heat exchangers that air cool the process stream.

Typical fields of application are:

Heating element sheaths

Acetic anhydride cracking furnaces

The solution-annealed version alloy 800H shall be considered for application temperatures above 600℃ (1112℉).

For applications requiring greater resistance to stress rupture and creep than Alloy 800, especially at temperatures above 1500℉ (816℃), alloys 800H and 800HT are used.

If the repeated lowering of operating temperatures below 700°C (1290°F) cannot be ruled out, or the operating temperature is permanently below 700°C (1290°F), the use of Alloy 800H is recommended. At temperatures below 600°C (1112°F), soft annealed Alloy 800 is generally used.

Alloy 800H and Alloy 800HT have a wide range of applications in areas of elevated temperatures in furnace construction, in the chemical industry, in environmental protection equipment, in the automotive industry and in power plants. Typical applications include furnace muffles, containers, bins, holders in various heat treatment plants and burner components.

Because of their resistance to carburization and nitriding, the alloys are furthermore used in the areas of:

■ Steam/hydrocarbon reformers

■ Ethylene pyrolysis

■ Equipment for acetic anhydride and ketone production.

 

6 CHEMICAL COMPOSITION (wt%):

Fe	Ni	Co	Cr	Cu	Ti
≥39.55	30.0-35.0	≤2.0	19.0-23.0	≤0.75	0.15-0.60
C	Al	Mn	Si	P	S
0.05-0.10	0.15-0.60	≤1.5	≤1.0	≤0.030	≤0.015

 

INCOLOY 800H, special requirements*

Carbon	0.08 max.
Aluminum + Titanium	0.4-0.7
ASTM grain size	Special

 

7 PHYSICAL PROPERTIES

(1) Density:8.00 g/cm³ (0.29 lb/in³)

(2) Melting point:1350-1400°C

(3) Specific heat:(0-100°C)460J/(kg·°C)

(4) Magnetic property:no

(5) Permeability(21°C) and (15.9 kA/m):1.014(Anneal), 1.009(Hot rolled)

(6) Curie temperature: Tc:-115°C

 

8 MECHANICAL PROPERTIES

The following properties are applicable to Alloy 800H and Alloy 800HT in the annealed condition in the following size ranges:

Sheet, plate up to 50 mm (1.97 in)

Strip up to 3 mm (0.12 in)

Rod, bar and forgings up to 250 mm (9.84 in)

For larger dimensions, the properties are to be agreed separately. The values are valid for longitudinal and transverse samples.

Mechanical short-time properties of solution annealed Alloy 800H and Alloy 800HT at room temperature and elevated temperatures; min. values according to VdTÜV data sheet 412.

Temperature		Yield strength Rp 0.2		Tensile strength Rm		Elongation A
°C	°F	MPa	ksi	MPa	ksi	%
20	68	170	24.7	450-700	65.3-101.5	Longitudinal 35
						Transverse 30
100	212	140	20.3	4251)	61.6
200	392	115	16.7	4001)	58
300	572	95	13.8	3901)	56.6
400	762	85	12.3	3801)	55.1
500	932	80	11.6	3601)	52.2
600	1,112	75	10.9	3001)	43.5

¹⁾ Average, for information only.

 

Mechanical properties at room temperature according to according to VdTÜV data sheet 412

Product form	Dimensions	Yield strength Rp 0.2	Tensile strength Rm	Elongation A
	mm	MPa	MPa	%
Sheet, plate, strip	≤ 50	≥ 170	450-700	≥ 30
Rod, bar	≤ 160	≥ 170	450-700	≥ 30
Forging	≤ 250	≥ 170	450-700	≥ 30

 

ISO V-notch impact toughness

Average values at room temperature, longitudinal.: 150 J/cm²

Average values at room temperature, transverse: 100 J/cm²

 

9 CORROSION RESISTANCE

The high nickel and chromium contents in Alloy 800H and Alloy 800HT ensure excellent resistance to oxidation. The alloys are also highly resistant to carburizing, nitriding and oxidation in sulphurous atmospheres. The protective oxide layer is adherent under static and cyclic thermal stress. Both materials are particularly resistant to carburization if a thin oxide film was formed by pre-oxidation.

The resistance to hydrogen embrittlement of Alloy 800H and 800HT is excellent, so that the alloys can be used in the production of hydrogen and steam/hydrocarbon reformers.

 

10 MICROSTRUCTURE

ASTM grain size:

Alloy 800: not specified

Alloy 800H: 5 or coarser

Alloy 800HT: 5 or coarser

Alloy 800H is an austenitic, solid-solution alloy which precipitate car- bides and γ' phase during high temperature ageing. Titanium nitrides, titanium carbides, and chromium carbides normally appear in the alloy’s microstructure. The nitrides are stable at all temperatures below the melting point and are therefore unaffected by heat treatment.

Chromium carbides precipitate in the alloy at temperatures between 1000-2000℉(540-1095℃). Consequently, alloy 800H is similar to other austenitic alloys in that it can be rendered susceptible to intergranular corrosion (sensitized) in certain aggressive environments by exposure to temperatures of 1000 to 1400℉ (540-760℃).

An important property of alloy 800H is its relative freedom from chloride stress-corrosion cracking. Extensive studies of stress-corrosion cracking of austenitic alloys in chloride solutions have shown that the tendency to crack decreases with increasing nickel content of alloy. For example, Inconel 600, with a nickel content of 76%, is considered to be immune to chloride-ion stress-corrosion cracking. Alloy 800H (32.5% Ni) can be made to crack in severe laboratory tests, but it has such high resistance that it is commonly used to replace materials that have failed in service from stress-corrosion cracking.

 

11 STANDARD SPECIFICATION

Alloy 800H is designated as UNS N08810 and Werkstoff Number 1.4876 and 1.4958. It is listed in NACE MR0175 / ISO15156 for oil and gas service. Alloy 800H is available as pipe, tube, sheet, strip, plate, round bar, flat bar, forging stock, hexagon and wire.

 

Rod, Bar, Wire, Forgings

ASTM B 408 & ASME SB 408 (Rod & Bar)

ASTM B 564 & ASME SB 564 (Forgings)

ASME Code Case 1325 (All Product Forms)

ASME Code Case 1949 (Forgings)

SAE AMS 5766 (Rod & Bar)

ISO 9723 (Rod & Bar)

ISO 9724 (Wire)

ISO 9725 (Forgings)

BS 3076NA15 (Rod & Bar)

BS 3075NA15 (Wire)

VdTÜV 412 (All Products)

 

Plate, Sheet, and Strip

ASTM A240 / ASME SA240 (Plate, Sheet, and Strip)

ASTM A480 / ASME SA480 (Plate, Sheet, and Strip)

ASTM B409 / ASME SB409 (Plate, Sheet, and Strip)

ASTM B906 / ASME SB906 (Plate, Sheet, and Strip)

 

ASME Code Case 1325 (All Product Forms)

ASME Code Case 2339 (Plate)

SAE AMS 5871 (Plate, Sheet, and Strip)

BS 3072NA15 (Plate & Sheet)

BS 3073NA15 (Strip)

VdTÜV 412 (All Products)

ISO 6208 (plate, sheet and strip)

 

Pipe and Tubes

ASTM B163 / ASME SB163 (Seamless Condenser & Heat Exchanger Tubes)

ASTM B407 / ASME SB407 (Seamless Pipe & Tubes)

ASTM B829 / ASME SB 829 (Seamless Pipe & Tubes)

ASTM B514 / ASME SB514 (Welded Pipe)

ASTM B775 / ASME SB775 (Welded Pipe)

ASTM B515 / ASME SB515 (Welded Tubes)

ASTM B751 / ASME SB751(Welded Tubes)

ASME Code Case 1325 (All Product Forms)

ASME N-20 (Cold Worked Seamless Condenser and Heat Exchanger Tubes for Nuclear Service)

BS 3074NA15 (Seamless Pipe & Tubes)

VdTÜV 412 (All Products)

ISO 6207 (Seamless Tubing)

 

Other Product Forms

ASTM B366 / ASME SB366 (Fittings)

 

12 COMPETITIVE ADVANTAGE

(1) More than 50 years experience of research and develop in high temperature alloy, corrosion resistance alloy, precision alloy, refractory alloy, rare metal and precious metal material and products.
(2) 6 state key laboratories and calibration center.
(3) Patented technologies.

(4) High performance.

 

13 BUSINESS TERM

Minimum order quantity	500 kilogram
Price	Negotiable
Packaging details	Water prevent, seaworthy transport, non-fumigation wooden box
Mark	As per order
Delivery time	90-120 days
Payment terms	T/T, L/C at sight, D/P
Supply ability	100 metric tons / Month