Nichroloy
Nichroloy is a clean, fine-grain, alloy steel produced by the electric furnace process and furnished rough-turned for applications requiring exceptionally high tensile strength and resistance to wear, shock and fatigue. Rigid quality control assures a steel of consistently high chemical and physical properties. For the TG&P version of Nichroloy, please see ACCURLOY.
Benefits of Nichroloy
| Longer Service Life:
Engineered to develop higher strength, finer finish, cleaner chemistry and better fatigue resistance than standard grades of alloys and carbon steels such as SAE 1045, 4140, 4150, 4340, etc. Precision Finish: Turned, ground and polished to very close tolerances, Nichroloy will save you time and money in machining and down-time. Availability: Baldwin International maintains one of the largest stocks of precision finished shafting in the U.S. With a full array of sizes from 1/4″ dia. to 9″ dia. in common 1/16″ increments, as well as metric sizes, we can supply your specific shaft how you want it and when you want it. |
 |
Compare Nichroloy to 4140
| Factors | 4140 | Nichroloy | Advantages of Nichroloy |
|---|---|---|---|
| Manufacturing Process | Open Hearth Furnace. Large heats, little uniform control | Small Electric Furnace heats | Greater control, less defects, cleaner steel which increases toughness and service life |
| Tensile Strength (Heat Treated 28-32 RC) | 125,000 PSI | 155,000 PSI Typical (Higher on smaller diameters) | Approximately 25% higher strength |
| Yield Strength (Heat Treated 28-32 RC) | 100,000 PSI | 130,000 PSI Typical (Higher on smaller diameters) | Approximately 25% higher strength |
| Stress Relieved & Machine Straightened | Optional – must be specified | Stress relieved at mill | Minimizes Bowing and “Walking” during machining |
| Low Sulphur Vacuum Degassed | Not a commercial practice | Degassed at mill | Builds toughness by removing impurities in the steel |
| Fatigue Resistance | Low Toughness | High degree of toughness | Higher endurance limit. Will minimize fatigue caused by twisting and flexing in use. |
| Wear Resistance | Hard and soft spots, Uneven wear | Uniform hardness | Uniform hardness and less decarburization give increased wear life. Tends to work-harden with wear. |
| Machinability | Not consistent | Uniform | Uniform grain and hardness offer better machinability |
Common Applications for Nichroloy
| Arbors Armature Shafts Axles Bolts Boring Bars Chain Links Chain Pins Clevices Conveyor Shafts and Rollers Crank Shafts / Pins Drag Line Parts Drift Pins Drill Shanks Drive Shafts Feed Screws Fittings Gears Gear Shafts Generator Shafts Grinder Spindles Gudgeons High Pressure Valve Studs Highly Stressed Shafting Hoist Hooks & Pins Hoist Shafts Hubs Impeller Shafts Jack Shafts Journals Lead Screws Line Shafts Machine Tool Pinions Magneto Shafts |
Mandrels Mining Machine Parts Motor Shafts Nuts Pinions Pins Piston Rods Power Shovel Shafts Propeller Shafts Push Rods Reamer Shafts Renecking Spinning Rollers Rings Screws Set Screws Shackles Skidding Tools Sleeves Sleeve Shafts Spindle Spinning Rollers Steam Shovel Parts Steering Knuckles Studs Tie Rods Thrust Shafts Tongs Transmission Screws Valve Stems Wearing Strips Worms Worm Gears Wrist Pins |
Nichroloy Size Range
| DIAMETER SIZE (INCHES) | ||
|---|---|---|
| 1/2 | 31/2 | 8 |
| 5/8 | 33/4 | 81/4 |
| 3/4 | 4 | 81/2 |
| 7/8 | 41/4 | 83/4 |
| 1 | 41/2 | 9 |
| 11/4 | 43/4 | 91/2 |
| 13/8 | 5 | 93/4 |
| 11/2 | 51/4 | 10 |
| 13/4 | 51/2 | 101/2 |
| 17/8 | 53/4 | 11 |
| 2 | 6 | 111/2 |
| 21/4 | 6 1/4 | 12 |
| 23/8 | 61/2 | 121/2 |
| 21/2 | 63/4 | 13 |
| 23/4 | 7 | 131/2 |
| 27/8 | 71/4 | 14 |
| 3 | 71/2 | 15 |
| 31/4 | 73/4 | 16 |
Nichrology comes in random and cut-to-length sizes up to 24 feet. Please inquire on your specific sizes.
Properties of Nichroloy
Typical As Delivered Mechanical Properties
| Hardness | Rockwell C 28 to 32 |
| Tensile Strength | 155,000 psi |
| Yield Strength | 130,000 psi |
| Reduction in Area | 50% |
| Elongation in 2″ | 20% |
| Grain Size | 95% of 8 on Shepherd fracturegrain size standards |
Heat Treatment
| Forging | 1900°F – 2100°F |
| Hardening | 1525°F – 1575°F (oil quench) |
| Annealing | 1425°F – 1500°F (212 BHN) |
| Normalizing | 1600°F – 1650°F |
| Tempering | (see chart) |
Temper immediately after removal from oil quench.
Tempering Chart
(based on 1/2″ dia. test specimen)
| DrawTemperature°F | Rockwell “C” | Tensile PSI | Yield PSI | Elongation in 2″% | Reduction in Area% |
|---|---|---|---|---|---|
| 400 | 54 | 312,000 | 274,000 | 12 | 35 |
| 500 | 52 | 296,000 | 262,000 | 12 | 37 |
| 600 | 50 | 273,000 | 240,000 | 12 | 38 |
| 800 | 47 | 256,000 | 234,000 | 12 | 42 |
| 1000 | 42 | 194,000 | 175,000 | 15 | 50 |