Type Analysis | Principal Features | Creep And Rupture Strength
Typical Tensile Properties | Typical Mechanical Properties | Fabrication Characteristics | Machining

Type Analysis

Principal Features

Excellent High-Temperature Strength, Thermal Stability, and Environment Resistance
Haynes 230 alloy is a nickel-chromium-tungsten-molybdenum alloy that combines excellent high temperature strength, outstanding resistance to oxidizing environments up to 2100°F (1149°C) for prolonged exposures, premier resistance to nitriding environments, and excellent long-term thermal stability. It is readily fabricated and formed, and is castable. Other attractive features include lower thermal expansion characteristics than most high-temperature alloys, and a pronounced resistance to grain coarsening with prolonged exposure to high-temperatures.

Easily Fabricated
Haynes 230 alloy has excellent forming and welding characteristics. It may be forged or otherwise hot-worked, providing that it is held at 2150°F (1177°C) for a time sufficient to bring the entire piece to temperature. As a consequence of its good ductility, 230 alloy is also readily formed by cold-working. All hot- or cold-working parts should be annealed and rapidly cooled in order to restore the best balance of properties. The alloy can be welded by a variety of techniques, including gas tungsten arc (GTAW), gas metal arc (GMAW), and resistance welding.

Heat-Treatment
Wrough 230 alloy is furnished in the solution heat-treated condition, unless otherwise specified. The alloy is solution heat-treated in the range of 2150 to 2275°F (1177°C) and rapidly cooled or water-quenched for optinum properties.
Annealing at temperatures lower than the solution heat-treating temperatures will produce some carbide precipitation in 230 alloy, which may marginally affect the alloy's strength and ductility.

Casting
Haynes 230 alloy may be cast using traditional air-melt sand mold or vacuum-melt investment casting foundry practices. Silicon levels at the high end of the specification range are recommended for enhanced fluidity. Castings may be used in either the as-cast or solution-heat-treated condition depending upon property requirements.

Applications
Haynes 230 alloy combines properties which make it ideally suited for a wide variety of component applications in the aerospace and power industries. It is used for combustion cans, transition ducts, flameholders, thermocouple sheaths, and other important gas turbine components. In the chemical process industry, 230 alloy is used for catalyst grid supports in ammonia burners, high-strength thermocouple protection tubes, high-temperature heat exchangers, ducts, high-temperature bellows, and various other key process internals.
In the industrial heating industry, applications for 230 alloy include furnace retorts, chains and fixtures, burner flame shrouds, recuperator internals, dampers, nitriding furnace internals, heat-treating baskets, grates, trays, sparger tubes, thermocouple protection tubes, cyclone internals, and many more.

Creep and Stress-Rupture Strength

Haynes 230 alloy is a solid-solution-strengthened material which combines excellent high-temperature strength with good fabricability at room temperature. It is particularly effective for very long-term applications at temperatures of 1200°F (649°C) or more, and is capable of outlasting stainless steels and nickel alloys by as much as 100 to 1 depending upon the temperature. Alternatively, the higher strength of 230 allows for the use of design section thickness as much as 75 percent thinner than lesser alloys with no loss in load-bearing capability.

Stress-Rupture Lives for Various Alloys at Fixed Test Condtions (Bar and Plate)*

*Based upon Larson-Miller extrapolation

Sheet - 2250°F (1232°C) Solution Anneal

*Significant Extrapolation of Data

Plate and Bar - 2250°F (1232°C) Solution Anneal

*Based upon limited data

ASME Vessel Code Allowance Stresses

Haynes 230 alloy is approved for ASME Vessel Code Section I and Section VIII Division 1 construction to 1650°F (899°C) under Code case No. 2063. Allowable stresseses are reprinted here by permission of the ASME.

Note (1)
Due to the relatively low yield strength of this material, these higher stress values were established at temperatures where the short time tensile properties govern to permit the use of these alloys where slightly greater deformation is acceptable. These higher stress values exceed 67%, but do not exceed 90% of the yield strength at temperature. Use of these stresses may result in dimensional changes due to permanent strain. These stress values are not recommended for flanges of gasketed joints or other applications where slight amounts of distortion can cause leakage or malfunction.

Typical Tensile Properties

Cold-Rolled and 2250°F (1232°C) Solution Annealed (Sheet)

Hot-Rolled and 2250°F (1232°C) Solution Annealed (Plate)

Room-Temperature Properties After Thermal Exposure (Plate)

Resistance To Grain Growth

Haynes 230 alloy exhibits excellent resistance to grain growth at high temperatures. As a consequence of its very stable primary carbides, 230 alloy can be exposed at temperatures as high as 2200°F (1204°C) for up to 24 hours without exhibiting significant grain growth. Materials such as Haynes 188 alloy or Hastelloy X alloy exhibit greater grain growth under such conditions, as would most iron-,nickel-, or cobalt-based alloys and stainless steels.

Grain Size For Alloy Exposed At Temperature For Various Times*
(ASTM Grain Size No.)

*Plate Product

Typical Physical Properties

Dynamic Modulus of Elasticity

Fabrication Characteristics

Heat Treatment
Haynes 230 alloy is normally final solution heat-treated at 2250°F (1232°C) for a time commensurate with section thickness. Solution heat-treating can be performed at temperatures as low as about 2125°F (1163°C), but resulting material properties will be altered accordingly. Annealing during fabrication can be performed at even lower temperatures, but a final, subsequent solution heat-treatment is needed to produce optimum properties and structure.

Typical Hardness Properties

Effect of Cold Reduction Upon Room-Temperature Tensile Properties*

*Based upon rolling reduction taken upon 0.120-inch (3.0 mm) thick sheet. Duplicate tests.

Welding

Haynes 230 alloy is readily welded by Gas Tungsten-Arc (TIG), Gas Metal-Arc (MIG) Shielded Metal-Arc (coated electrodes), and resistance welding techniques. Its welding characteristics are similar to those for Hastelloy X alloy. Submerged-Arc welding is not recommended as this process is characterized by high heat input to the base metal and slow cooling of the weld. These factors can increase weld restraint and promote cracking.
Base Metal Preparation
The joint surface and adjacent area should be throughly cleaned before welding. All grease, oil, crayon marks, sulfur compounds and other foreign matter should be removed. It is preferable, but not necessary, that the alloy be in the solution-annealed condition when welded.
Filler Metal Selection
Haynes 230-W filler wire (AWS A5.14, NiCrWMo-1) is recommended for joining 230 alloy by Gas Tungsten-Arc or Gas Metal-Arc welding. Coated electrodes of 230-W alloy are also available for Shielded Metal Arc welding in non-ASME code construction. For dissimilar metal joining of 230 alloy to nickel-, cobalt-, or iron-base materials, 230-W filler wire, Haynes 556 alloy, Hastelloy S alloy (AMS 5838) or Hastelloy W alloy (AMS 5786, 5787) welding products may all be considered, depending upon the particular case.
Preheating, Interpass Temperatures and Post-Weld Heat Treatment
Preheat is not usually required so long as base metal to be welded is above 32°F (0°C). Interpass temperatures generally should be low. Auxiliary cooling methods may be used between weld passed, as needed, providing that such methods do not introduce contaminants. Post-weld heat treatment is not normally required for 230 alloy.

Nominal Welding Parameters

Nominal welding parameters are provided as a guide for performing typical operations. These are based upon welding conditions used in our laboratories. Details are given for GTAW, GMAW ans SMAW welding.

Automatic Gas Tungsten-Arc Welding

Square Butt Joint - No Filler Metal Added

Manual Gas Tungsten Arc Welding

V-or U-Groove - All thicknesses 0.125" (3.6 mm) or greater

Gas Metal Arc Welding

Short Circuiting Transfer Mode - All Thicknesses 0.090" (2.3 mm) or greater

Typical Shielded Metal Arc Welding Parameters (Flat Position)*

*DCEP

Machining

Haynes 230 alloy is similar in machining characteristics to other solid-solution-strengthened nickel-based alloys. As a group these alloys are classified as a moderate to difficult ot machine; however, it should be emphasized that they can be machined using conventional methods at satisfactory rates. As these alloys will work-harden rapidly, the keys to successful machining are to use slower speeds and feeds, and to take heavier cuts than would be used for machining stainless steels.

Normal Roughing (Turning/Facing)
Use carbide C-2/C-3 grade tool
Speed : 90 surface feet/minute
Feed: 0.010 in./revolution
Depth of cut: 0.150 in.
Negative rake square insert, 45° SCEA(1) 1/32 in. nose radius. Tool holder: 5° negative back and side rakes.
Lubricant: Dry(2), Oil(3) or water-base(4,5)

Finishing (Turning/Facing)
Use carbide C-2/C-3 grade tool
Speed: 95-100 surface feet/minute
Feed: 0.005-0.007 in./revolution
Depth of cut: 0.040 in.
Positive rake square insert, possible, 45° SCEA, 1/32 in. nose radius. Tool holder: 5° positive back and side rakes.
Lubricant: Dry or water-base

Drilling
Use high speed steel M-33/M-40 series(6)/or T-15 grade*
Speed: 10-15 surface feet/minute (200 RPM maximum for 1/4 in. diameter or smaller)
Lubricant: Oil or water-base. Use coolant feed drills if possible
Short, heavy-web drills with 135° crank shaft point. Thinning of web at point may reduce thrust.
Feed (per revolution)
0.001 in. rev. 1/8 in. dia
0.002 in. rev. 1/4 in. dia
0.003 in. rev. 1/2 in. dia
0.005 in. rev. 3/4 in. dia
0.007 in. rev. 1 in. dia.
*Carbide drills not recommended, but may be used in some set-ups.

NOTES:

• 1. SCEA-Side cutting edge angle, or lead angle of the tool.

• 2. At any point where dry cutting is recommended, an air jet directed on the tool may provide substantial tool life increases. A water-base coolant mist may also be effective.

• 3. Oil coolant should be a premium quality, sulfochlorinated oil with extreme pressure additives. A viscosity at 100°F of from 50 to 125 SSU is standard.

• 4. Water-base coolant should be a 15:1 mix of water with either a premium quality, sulfochlorinated water soluble oil or a chemical emulsion with extreme pressure additives.

• 5. Water-base coolants may cause chipping or rapid failure of carbide tools in interrupted cuts.

• 6. M-40 series High Speed Steels include M-41 through M-46 at time of writin, others may be added, and should be equally suitable.

Haynes 230 - Current Inventory Stock