Jul 4 2013
Topics Covered
Introduction
Chemical Composition
Physical Properties
Mechanical Properties
Other Designations
Fabrication
Machinability
Welding
Hot working
Cold Working
Annealing
Applications
Introduction
INCOLOY alloys belong to the category of super-austenitic stainless steel alloys. Nickel, chromium and iron are the principal constituents of this alloy. By adding different additives this alloy can be made to resist different chemical reagents. Good strength and resistance to corrosion are characteristics of these alloys.
Additives such as molybdenum and nitrogen are added to the alloy in order to increase its resistance to pitting, crevice corrosion and thermal stability. The nickel and chromium content extend the corrosion resistance of this alloy over a wide range of environments like non-oxidizing acids, aqueous, caustic chlorides, halides and pulp-mill bleaches. This alloy is available in the form of bars, billets, sheets, round, plate, strips and wire.
This datasheet will look into the chemical composition, properties and applications of INCOLOY 25-6MO.
Chemical Composition
The chemical composition of INCOLOY alloy 25-6MO is given in the following table.
|
Element |
Content (%) |
|
Iron, Fe |
47.3 |
|
Nickel, Ni |
24-26 |
|
Chromium, Cr |
19-21 |
|
Molybdenum, Mo |
6-7 |
|
Manganese, Mn |
≤2 |
|
Others |
Remainder |
Physical Properties
The following table discusses the physical properties of INCOLOY alloy 25-6MO.
|
Properties |
Metric |
Imperial |
|
Density |
8.03 gm/cm3 |
0.290 lb/in3 |
Mechanical Properties
The mechanical properties of INCOLOY alloy 25-6MO are tabulated below.
|
Properties |
Metric |
Imperial |
|
Tensile strength(annealed) |
689 MPa |
100 ksi |
|
Yield strength(annealed) |
331 MPa |
48 ksi |
|
Elongation at Break( in 2 in 50 mm) |
≥42% |
≥42% |
|
Hardness, Rockwell B |
86 |
86 |
|
Modulus of Elasticity |
188 GPa |
27300 ksi |
|
Poissons Ratio |
0.33 |
0.33 |
Other Designations
Some of the designations used to denote INCOLOY alloy 25-6MO are listed below:-
Fabrication
Machinability
Machining characteristics of this INCOLOY alloy 25-6MO is similar to that of other austenitic alloys.
Machining of INCOLOY alloy 25-6MO should be done at a slightly lower speed when compared stainless steel using rigid tooling and optimum lubrication and cooling.
Welding
INCOLOY alloy 25-6MO can be welded by gas metal arc welding, gas tungsten arc welding, shielded arc welding, plasma arc welding and submerged metal arc welding. The filler metal and electrodes are usually made of INCONEL alloy.
Hot working
INCOLOY alloy 25-6MO can be hot worked at temperature ranges of 980-1150°C (1800-2100°F).
Cold Working
Cold rolling may be done on the alloy after annealing.
Annealing
INCOLOY alloy 25-6MO should be annealed at temperatures greater than 1175°C (2150°F).
Applications
The INCOLOY alloy 25-6MO is used in the following applications:
-
Chemical and food processing
-
Paper bleaching plants
-
Marine and offshore platform equipment
-
Air pollution control systems
-
Salt plant evaporators
-
Condenser tubes, service water pipes and feed water heaters.