Inconel 600

Inconel® 600 is a member of the Inconel family of superalloys. A standard engineering material, this versatile nickel-chromium alloy provides high resistance to corrosion and heat, good oxidation resistance at higher temperatures, and good resistance in carbonizing and chloride-containing environments. Alloy 600 also provides excellent mechanical properties, with high strength and good workability. Ideal for applications in the food processing, nuclear engineering, aerospace, thermal processing, and chemical industries, this alloy handles temperatures ranging from cryogenic to 2000° F (1095° C.)

Inconel 600’s unique composition enables it to resist a broad range of corrosives. It’s superior to commercially pure nickel under oxidizing conditions, thanks mainly to its chromium content. While its high nickel content allows it to retain considerable resistance under reducing conditions as well as excellent resistance to alkaline solutions. Alloy 600 has fair resistance to strongly acidizing solutions, but the oxidizing of dissolved air isn’t enough to generate complete passivity and freedom of attack by mineral acids and organic acids.

Existing several forms in commerce, the most used are:

• AMS 5540 (Plate, Sheet, and Strip)
• AMS 5580 (Tube, and custom Tubing)
• AMS 5665 (Bar, Forging, Ring, and Tube)
• AMS 5961 Wire

Standard Specification

• UNS N06600
• AMS 5540
• ASTM B 168
• ASME SB 168
• 10204
• EN 2.4816

Chemical Composition, %

Applications of Inconel 600

Alloy 600 can be used in a variety of applications as follows:

• Jet engines
• Exhaust liners
• High-temperature airframe components
• High-temperature engine
• Lockwire
• Turbine seals
• Combustion-can liners
• Containment rings in gas turbines
• Diffuser assembles
• Jet-engine igniters
• Chemical and process industries
• Bubble towers
• Condensers for processing of fatty acids
• Evaporator tubes
• Flaking trays
• Heaters
• Stills
• Tube sheets
• Catalyst grid supports in equipment for nitric acid production
• Combustor components
• Condenser tubes in sour-water
• Insulating cans in ammonia reformers
• Process heaters
• Strippers
• Thermal processing
• Retorts
• Muffles
• Roller hearths
• Furnace components
• Heat-treating baskets
• Heat-treating trays
• Petrochemical processing
• Air preheaters
• Catalyst regenerators
• Waste processing
• Combustion chambers in solidwaste incinerators
• Thermal reactors in exhaust systems of gasoline engines
• Power generation
• Ashhandling systems
• Grid barriers
• Superheater tube supports

 Physical Properties

The nickel content above includes cobalt. A nickel-chromium alloy with good oxidation resistance at high temperatures and resistance to chloride-ion stress-corrosion cracking, corrosion by high-purity water, and caustic corrosion. Used for furnace components, in chemical and food processing, in nuclear engineering, and for sparking electrodes. Standard product forms are round, hexagon, extruded section, flats, forging stock, pipe, tube, plate, sheet, strip, and wire.

Mechanical Properties

Coefficient of linear thermal expansion 10^-6 K^-1 between 20°C and 

• *Coefficient A: the instantaneous coefficient of thermal expansion, unit: 10^-6 (inch/inch/°F).
• *Coefficient B: the mean coefficient of thermal expansion in going from 70°F to indicated temperature, unit: 10⁻⁶ (inch/inch/°F).
• *Coefficient C: the linear thermal expansion in going from 70°F to indicated temperature, unit: inch /100 ft.
• *All values are in conformance with ASME BPVC Section II Part D Properties (Customary).

Work condition and Heat Resistance of Inconel 600

INCONEL alloy 600 is widely used in the furnace and heat-treating fields for retorts, boxes, muffles, wire belts, roller hearths, and similar parts which require resistance to oxidation and to furnace atmospheres. The alloy is the standard material for nitriding containers because of its resistance to nitrogen at high temperatures. The alloy’s resistance to oxidation and scaling at 1800°F (980°C) is shown in Figure 1 below.

Figure 1 - Results of cyclic oxidation tests at 1800°F (980°C). Cycles were 15 minutes of heating and 5 minutes of cooling in the air

The weight-loss determinations used to obtain the curves in Figure 1 indicate the ability of a material to retain a protective oxide coating under conditions of cyclic exposure to the temperature.

INCONEL alloy 600 has good resistance to carburization. Table 1 below shows the results of tests in high-temperature carburizing atmospheres. INCONEL alloy 600 resists attack by sulfur compounds at moderate temperatures, but it is subject to sulfidation in high-temperature, sulfur-containing environments. Molybdenum disulfide, a lubricant sometimes used to aid parts assembly, should not be used if the material will be subsequently exposed to temperatures above 800°F (427°C).

Table 1 - High-temperature test

Note: ^a Atmosphere also contained 5% argon.

Heat Treatment of Inconel 600

The behaviour of the alloy during heating is governed by a number of interacting variables: the amount of cold work, grain size, chemical composition, and dimensions of the material. Consequently, times and temperatures for heat treatment are usually experimentally determined.  In general, an annealing treatment of about 1850°F/15 min (1010°C/15 min) will produce soft material. Brief exposure to 1900°F (1040°C) will give soft material without producing a coarse grain structure. Grain growth does not occur until the alloy is heated to about 1800°F (980°C). At that temperature, the finely dispersed carbide particles in the alloy’s microstructure, which inhibit grain growth, begin to coalesce. The solution of the carbides begins at about 1900°F (1040°C). Treatment for 1 to 2 hr at 2000° to 2100°F (1090° to 1150°C) dissolves the carbides completely and results in increased grain size. This solution treatment is beneficial in obtaining maximum creep and rupture strength.

In general, a material with a fine-grain structure is preferred because it has better corrosion resistance and higher tensile, fatigue and impact strength. Fine-grain material is preferred for all low-temperature applications, most intermediate-temperature applications, and those high-temperature applications that require resistance to shock and corrosion.

Grain size is dependent on processing. Hot-rolled products will usually have a small grain size because they are finished at relatively low temperatures. Annealing has little effect on the grain size of hot-rolled material. Cold-drawn or cold-rolled material, in either the cold-worked or annealed condition, will have a small grain size. Solution treatment will produce a coarse grain structure in either hot-worked or cold-worked material.

The time and temperatures required for recrystallization of cold-worked material vary widely, depending on the amount of cold work and the specific composition. Table 2 below shows the times and temperatures required for the recrystallization of fine-grain sheet after various amounts of cold reduction.

Hot and Cold Forming

The normal hot-working temperature range for INCONEL alloy 600 is 1600° to 2250°F (870° to 1230°C). Heavy hot work should be done between 1900° and 2250°F (1040° and 1230°C); light work can be continued down to 1600°F (870°C). The alloy has low ductility at temperatures between 1200° and 1600°F (650° and 870°C) and should not be worked in that range. High tensile properties can be developed in the material by careful working at temperatures below 1200°F (650°C). INCONEL alloy 600 is cold-formed by the standard processes used for steel and stainless steel. The rate of work hardening, as shown in Figure 2 below, is greater than that of mild steel but less than the rate of Type 304 stainless steel.

Table 2 - Effect of Cold Work on Recrystallization Temperature of Cold-Rolled, Fine-Grain Sheet

Figure 2 - Work-hardening rates of INCONEL alloy 600 and other metals.

 Corrosion Resistance of Inconel 600

The composition of INCONEL alloy 600 enables it to resist a variety of corrosives. The chromium content of the alloy makes it superior to commercially pure nickel under oxidizing conditions and its high nickel content enables it to retain considerable resistance under reducing conditions. The nickel content also provides excellent resistance to alkaline solutions. The alloy has fair resistance to strongly oxidizing acid solutions. However, the oxidizing effect of dissolved air alone is not sufficient to ensure complete passivity and freedom from attack by air-saturated mineral acids and certain concentrated organic acids

Stress-Corrosion Cracking

Austenitic chromium-nickel stainless steels sometimes fail catastrophically by stress-corrosion cracking. This type of failure is generally associated with an environment containing chlorides as well as with stress, water, dissolved oxygen, and other factors. The tendency of austenitic alloys to crack transgranularly in chloride solutions decreases as the nickel content of the alloy is increased. INCONEL alloy 600, with a minimum nickel content of 72%, is virtually immune to chloride-ion stress-corrosion cracking

INCONEL alloy 600 is subject to stress-corrosion cracking in high-temperature, high-strength caustic alkalies. Material for such service should be fully stress-relieved at 1650°F/1 hr or 1450°F/4 hr (900°C/1 hr or 790°C/4 hr) prior to use, and operating stresses should be kept to a minimum. Stress-corrosion cracking may occur also in the presence of mercury at elevated temperatures. The recommendations given for caustic-alkali service should be followed if the alloy is used in an application that involves contact with mercury at high temperatures

 Machinability

INCONEL alloy 600 is slightly more machinable than Type 304 stainless steel and slightly less machinable than Type 303 free-machining stainless steel. The alloy is best handled on heavy-duty equipment using cutting tools large and heavy enough to withstand the loads and quickly dissipate the heat generated. Tools must be sharp and have the proper geometry. More information on machining can be obtained from our specialist ENG.

  Welding of Inconel 600

INCONEL alloy 600 is readily joined by conventional welding processes. Welding materials for joining alloy 600 are INCONEL Welding Electrode 182 for shielded metal-arc welding*, INCONEL Filler Metal 82 for gas tungsten-arc and gas metal-arc welding, and INCONEL Filler Metal 82 and INCOFLUX 4 Submerged Arc Flux for the submerged-arc process. Table 3 below compares thermal-expansion rates of weld metals with those of wrought alloy 600. Impact-strength values for all-weld-metal deposits of INCONEL Welding Electrode 182 are listed in Table 4.

Room-temperature tensile properties of welds made with INCONEL Filler Metal 82 and Welding Electrode 182 are given in Table 5. High-temperature tensile properties of welds made with those materials are shown in Figures 3 and 4. Stress-rupture properties of weld metals are given in Table 6.

Welds made with INCONEL Welding Electrode 182 may have decreased ductility after extended exposure to temperatures of 1000° to 1400°F (540° to 760°).

 Table 3 - Thermal Expansion of Weld Metals

Note: ^a From 70°F (21°C) to temperature shown.

Table 4 - Impact Strength (Charpy Keyhole) of INCONEL Welding Electrode 182 Deposited Weld Metal

Note: ^a Values at 70°F (21°C) and -110°F (-79°C) are the average of three tests; value at -320°F (-196°C) is the average of two tests.

 Table 5 - Room-Temperature Tensile Properties of All-Weld-Metal Deposits

Note:

• ^a 0.505-in. (12.83 mm)-dia. specimen.
• ^b 0.252-in. (6.40-mm)-dia. specimen.

Table 6 - Rupture Strength of All-Weld-Metal Deposits

Note: ^a Values in bold are extrapolated

Specification Chart of Inconel Filler Metal 82

Welding Procedure of ERNiCr-3 Tig Rod

Nickel Alloy ERNiCr-3 Mig Rod Mechanical Properties

Types of Inconel Alloy 600 Filler Wires / Welding Electrode

Inconel 600 Filler Wire  AWS A5.14 ERNiCr-3 Filler Wire UNS N06600 Filler Wire 2.4816 Filler Wire Alloy 600 Export Quality Filler Wires AWS A5.11 ENiCrFe-3 Inconel 600 Filler Wires

AWS A5.11 ENiCrFe-3 Inconel 600 Filler Wires  AWS A5.11 ENiCrFe-3 Inconel 600 Filler Wires UNS N06600 Welding Electrode 2.4816 Welding Wire Alloy 600 Export Quality Welding Electrodes AWS A5.11 ENiCrFe-3 Inconel 600 Welding Wires

Inconel 600 TIG Welding Wire AWS A5.14 ERNiCr-3 TIG Welding Wire UNS N06600 TIG Filler Wire 2.4816 TIG Welding Wire Alloy 600 Export Quality TIG Welding Wires AWS A5.11 ENiCrFe-3 Inconel 600 TIG Welding Wire

Inconel 600 MIG Welding Wire AWS A5.14 ERNiCr-3 600 MIG Welding Wire UNS N06600 MIG Filler Wire  2.4816 MIG Welding Wire Alloy 600 Export Quality MIG Welding Wires AWS A5.11 ENiCrFe-3 Inconel 600 MIG Welding Wire

Price List of UNS N06082 Electrode

Inconel 600 Welding Wire Composition Chart

AWS 5.14 ERNiCr-3 Alloy 82  - Welding wire Mechanical Strength

Inconel 600 electrode suppliers