Introduction to ASTM B463 Standard:
ASTM B463 is a standard specification established by the American Society for Testing and Materials (ASTM) that outlines the requirements for UNS N08020, UNS N08026, and UNS N08024 alloy sheet and plate.
Included Grades and Chemical Composition:
ASTM B463 covers three grades of nickel-iron-chromium alloys, each with its unique chemical composition:
1. Alloy 20 UNS N08020 (Carpenter 20, W.NR. 2.4660): Comprises nickel, chromium, iron, and copper, with additions of molybdenum and niobium.
2. UNS N08026: This grade typically consists of nickel, chromium, iron, and molybdenum, with controlled levels of copper, tungsten, and nitrogen.
3. UNS N08024: Contains nickel, chromium, iron, and molybdenum, with additions of copper, niobium, and nitrogen.
| Element | Composition,% | ||
| UNS N08026 | UNS N08020 | UNS N08024 | |
| Carbon,max | 0.03 | 0.07 | 0.03 |
| Manganese,max | 1.00 | 2.00 | 1.00 |
| Phosphorus,max | 0.03 | 0.045 | 0.035 |
| Sulfur,max | 0.03 | 0.035 | 0.035 |
| Silicon,max | 0.50 | 1.00 | 0.50 |
| Nickel | 33.00-37.20 | 32.00-38.00 | 35.00-40.00 |
| Chromium | 22.00-26.00 | 19.00-21.00 | 22.50-25.00 |
| Molybdenum | 5.00-6.70 | 2.00-3.00 | 3.50-5.00 |
| Copper | 2.00-4.00 | 3.00-4.00 | 0.50-1.50 |
| Columbium(Nb)+tantalum | ... | 8×carbon-1.00 | 0.15-0.35 |
| Nitrogen | 0.10-0.16 | ... | ... |
| Iron | remainder | remainder | remainder |
ASME SB 463 Mechanical Properties:
The mechanical properties of ASTM B463 alloys vary depending on factors such as grade, thickness, and heat treatment. Common mechanical properties include tensile strength, yield strength, elongation, and hardness.
| Tensile Strength, min |
Yield Strength,A min | ElongationB in 2 in. (50.8 mm), min,% |
|||||
| ksi | MPa | ksi | MPa | ||||
| 80 | 551 | 35 | 241 | 30 | |||
| Hardness Number,maxC | |||||||
| Brinell | Rockwell B | ||||||
| 217 | 95 | ||||||
AYield strength shall be determined by the offset method at 0.2 % limiting permanent set in accordance with Test Methods E 8. An alternative method of determining yield strength may be based on a total extension under load of 0.5 %.
BElongation for thickness, less than 0.015 in. (0.38 mm) shall be 20 % minimum, in 1 in. (25.4 mm).
CEither Brinell or Rockwell B hardness is permissible.
ASTM B463 Sheet And Plate Dimensions:
ASTM B463 specifies dimensions for sheets and plates, including thickness, width, and length requirements to ensure product uniformity and quality.
- cold rolled plate-material 3⁄16 to 3⁄8in. (4.76 to 9.52 mm), inclusive in thickness and over 10 in. (254.0 mm) in width.
- hot rolled plate-material 3⁄16 in. (4.76 mm) and over in thickness and over 10 in. (254.0 mm) in width.
- plate-material 3⁄16 in. (4.75 mm) and over in thickness and over 10 in. (254.0 mm) in width.
- sheet-material under 3⁄16 in. (4.75 mm) in thickness and 24 in. (609.6 mm) and over in width. Material under 3⁄16in. (4.75 mm) in thickness and in all widths with No. 4 finish.
- strip-material under 3⁄16 in. (4.75 mm) in thickness and under 24 in. (609.6 mm) in width.
Production Processes:
The production processes for ASTM B463 materials may include methods such as hot rolling, cold rolling, annealing, and surface treatment to achieve the desired properties and dimensions.
Heat Treatment- UNS N08020 Alloy shall be furnished in the stabilize-annealed condition. UNS N08026 Alloy shall be furnished in the solution-annealed condition. UNS N08024 Alloy shall be furnished in the annealed condition.
NOTE 2-The recommended annealing temperatures are 1800 to 1850°F (982 to 1010°C) for UNS N08020, 2050 to 2200°F (1121 to 1204°C) for UNS N08026, and 1925 to 1975°F (1052 to 1079°C) for UNS N08024.
Quality Testing Methods:
Quality testing methods for ASTM B463 materials may include:
- Chemical Composition Analysis: Performed using techniques like optical emission spectroscopy (OES) or inductively coupled plasma (ICP) analysis to verify alloy composition.
- Mechanical Testing: Involves tensile testing, hardness testing, and impact testing to assess mechanical properties and ensure material integrity.
- Dimensional Inspection: Utilizes instruments like calipers, micrometers, and gauges to verify dimensions and tolerances.
- Non-Destructive Testing (NDT): Includes methods like ultrasonic testing (UT) and radiographic testing (RT) to detect internal defects without compromising the integrity of the material.
ASTM B463 N08020 Plate Applications:
ASTM B463 nickel-iron-chromium alloys find applications in various industries, including:
- Chemical processing
- Petrochemicals
- Pharmaceuticals
- Food processing
- Marine engineering
ASTM Standards:
- A 262 Practices for Detecting Susceptibility to Intergranular Attack in Austenitic Stainless Steels
- B 880 Specification for General Requirements for Chemical Check Analysis Limits for Nickel, Nickel Alloys and Cobalt Alloys
- E 8 Test Methods for Tension Testing of Metallic Materials
- E 10 Test Method for Brinell Hardness of Metallic Materials
- E 18 Test Methods for Rockwell Hardness and Rockwell Superficial Hardness of Metallic Materials
- E 29 Practice for Using Significant Digits in Test Data to
- Determine Conformance with Specifications
- E 140 Hardness Conversion Tables for Metals
- E 1473 Test Methods for Chemical Analysis of Nickel, Cobalt, and High-Temperature Alloys
Conclusion:
ASTM B463 standardizes the requirements for nickel-iron-chromium alloys in sheet and plate forms, ensuring their suitability for a wide range of industrial applications. Compliance with these standards guarantees the quality, reliability, and performance of these materials in demanding environments.
