INCOLOY 800H/HT (INCOLOY 800H/HT) is an austenitic alloy widely used in high-temperature bearing structures. The high strength of 800H/HT is due to the addition of carbon, aluminum, and titanium and the annealing at a minimum [SCALE STEEL]temperature of 1149 ° C to achieve grain size ASTM5 or coarter.
Introduction for INCOLOY 800H/HT
For 800 H/HT under 787 ° C, 82(ER NicR-3) wire is used for welding.R A 330-04(N08334) wire has A matching coefficient of thermal expansion and higher strength.For maximum mechanical strength, use wire 617(ErNICrcomo-1) or wire 117(EnICRcomo-1).
In order to avoid grain boundary cracking caused by possible [SCALE STEEL]stress relaxation of 800H/HT welded parts above 538 ° C, post-weld heat treatment at 899 ° C is required. The heat preservation time shall be maintained for one hour (at least half an hour / 25mm thickness) per 25mm thickness according to the material thickness, followed by air cooling.
ASME: SB-409, SB-408, SB-407 Code Case 1325. ASME: SB-409, SB-408, SB-407
Chemical Composition for INCOLOY 800H/HT %
Cr Ni Mn Si Al Ti Al+Ti C Cu P S Fe
MIN 19 30 -- -- 0.15 0.15 0.85 0.06 -- -- -- 39.5
MAX 23 35 1.5 1 0.6 0.6 1.2 0.1 0.75 0.045 0.015 --
Material features high ASME VIII design allowable stress value (allowable temperature up to 1650 ° F) good oxidation resistance [SCALE STEEL]at high temperatures (up to 1900 ° F) resistance to chloride stress corrosion cracking the main application of ethylene cracking furnace quench boiler hydrogen manufacturing conversion furnace a furnace fixation of trachea, pigtail tube inside the gasifier pieces of electric heating elements the physical properties of casing density: 0.287 lb/in3
MELTING POING RANGE: 2475- 2525°F
TEM, °F 70 1400 1600 1800
THERMAL EXPANSIVITY*, in/in°F x 10-6 -- 9.9 10.2 --
THERMAL CONDUCTIVITY, 6.7 13.8 15.1 17.8
Btu · ft/ft2 · hr · °F
ELASTICITY MODULUS, 28.5 21.1 19.2 --
psi x 10 6
TEM, °F 70 1000 1200 1400 1600 1800
TENSILE STRENGTH, ksi 77 63.5 55.7 32.3 18.6 10.2
YIELD STRENGTH, ksi 29 16.5 14.8 14.4 11.6 8.9
ELONGATION, % 52 51 50 78 120 120
TYPICAL CREEP FRACTURE PROPERTIES
TEM, °F 1400 1600 1800
MIN CREEP RATE 0.0001%/Hour, ksi 6 3.6 1.05
10000小时断裂强度, ksi 7.3 3.5 1.2
PHYSICAL PROPERTY FOR Incoloy 800H:
DENSITY 8.0 g/cm3
MELTING POINT 1350-1400 ℃
800H Alloy Has The Following Characteristics:
1. Excellent corrosion resistance in[SCALE STEEL] water-based media with extremely high temperature up to 500℃
2. Excellent resistance to stress corrosion
3. Good processability
The Metallographic Structure of Incoloy 800H:
800H is a face-centered cubic lattice structure.The extremely low carbon content and the increased Ti:C ratio increase the structural stability and maximum resistance to sensitization and intercrystalline corrosion.The low temperature annealing at about 950℃ ensures the fine crystal structure.
Incoloy 800H Corrosion Resistance:
800H corrosion resistance of many corrosive [SCALE STEEL]media.Its high nickel content makes it have good resistance to stress corrosion cracking under water corrosion conditions.The high chromium content makes it more resistant to spot corrosion and crack corrosion cracking.The alloy has good corrosion resistance to nitric acid and organic acid, but limited corrosion resistance in sulfuric acid and hydrochloric acid.In addition to the possibility of spot corrosion in halides, it has good corrosion resistance in oxidizing and non-oxidizing salts.It is also very resistant to corrosion in water, steam and a mixture of steam, air and carbon dioxide.
1. Nitric acid condenser -- resistant to nitric acid corrosion
2. Steam heating tubes -- excellent mechanical properties
3. Heating element tubes -- excellent [SCALE STEEL]mechanical properties
For applications up to 500℃, the alloy is supplied in annealed state.Typical creep fracture properties