SAE AMS 6543C pdf download

SAE AMS 6543C pdf download.Steel, Bars and Forgings,Maraging 2.0Cr – 10Ni – 8.0Co – 1.0Mo (0.10-0.14C)Double Vacuum Melted, Solution Heat Treated.
1.1 Form:
This specification covers a pi-emium aircraft-quality maraging steel in the form of bats 0.50 inch (12.7 mm) and over in nominal diameter or least distance between parallel sides, forgings, and forging stock.
1.2 Application:
These products have been used typically for heat treated parts requiring a combination of high
strength. toughness, and weldability, but usage is not limited to such applications.
2. APPLICABLE DOCUMENTS:
The issue of the following documents in effect on the date of the purchase order forms a part of this specification to the extent specified herein. The supplier may work to a subsequent revision of a document unless a specific document issue is specified. When the referenced document has been canceled and no superseding document has been specified. the last published issue of that document shall apply.
2.1 SAE Publications:
Available from SAE, 400 Commonwealth Drive, Warrendale. PA 15096-0001.
AMS 2248 Chemical Check Analysis Limits. Corrosion and Heat Resistant Steels and Alloys. Maraging and Other Highly-Alloyed Steels, and Iron Alloys
AMS 2251 Tolerances. Low-Alloy Steel Bars
MAM 2251 Tolerances, Metric, Low-Alloy Steel Bars
AMS 2370 Quality Assurance Sampling and Testing, Carbon and Low-Alloy Steel Wrought Products and Forging Stock
3.1.1 Check Analysis: Composition variations shall meet the applicable requirements of AMS 2248. No variation is permitted for oxygen and nitrogen.
3,2 Melting Practice:
Shall be multiple melted using vacuum induction melting followed by vacuum consumable electrode remelting.
3.3 Condition:
The product shall be supplied in the following condition: hardness shall be determined in accordance with ASTM A 370:
3.3.1 Bars and Forgings: Hot finished, solution heat treated, and descaled, having hardness not lower than 42 HRC, or equivalent (See 8.2).
3.3.2 Forging Stock: As ordered by the forging manufacturer.
3.4 Heat Treatment:
Bars and forgings shall be solution heat treated as in 3.4.1 or 3.4.2, as applicable, holding at heat for sufficient time to ensure complete transformation, and quenching in agitated water sufficiently cool (See 8.3) to develop the mechanical properties specified herein. Pyrometry shall be in accordance with AMS 2750.
3.4.1 Product 2.0 Inches (51 mm) and Under in Nominal Section Thickness: Shall be solution heat treated by heating in air to 1525 °F ± 25 (829°C ± 14) and quenching.
3.4.2 Product Over 2.0 Inches (51 mm) in Nominal Section Thickness: Shall be solution heat treated by heating in air to 1650 °F ± 25 (899 °C ± 14), quenching, reheating to 1525°F ± 25 (829°C ± 14), and quenching.
3.5 Properties:
The product shall conform to the following requirements: tensile and impact testing shall be performed in accordance with ASTM A 370:
3.5.1 Bars and Forgings:
3.5.1.1 As Solution Heat Treated:
3.5.1.1.1 Macrostructure: Visual examination of transverse full cross-sections from bars, forgings, and forging stock, etched in hot hydrochloric acid in accordance with ASTM A 604. shall show no pipe or cracks. Porosity, segregation, inclusions, and other imperfections for product 36 square inches (232 cm2) and under in nominal cross•sectional area shall be no worse than the macrographs of ASTMA 604 shown in Table 2.
3.5.12.3 Fracture Toughness When Specified: Acceptance criteria and method of test shall be as established by purchaser.
3.5.2 Forging Stock: When a sample of stock is forged to a test coupon and heat treated as in 3.4 and
3.5.1.2, specimens taken from the heat treated coupon shall conform to the requirements of
3.5.1.2.1 and 3.5.1.2.2. If specimens taken from the stock after heat treatment as in 3.4 and
3.5.1.2 conform to the requirements of 3.5.1.2,1 and 3.5.1.2.2. the tests shall be accepted as
equivalent to tests of a forged coupon.
3.6 Quality:
The product, as received by purchaser, shall be uniform in quality and condition, sound, and free from foreign materials and from imperfections detrimental to usage of the product.
3.6.1 Bars ordered hot rolled or cold drawn or ground, turned, or polished, shall, after removal of the standard machining allowance In accordance with AS1 182, be free from seams, laps, tears, and cracks open to the ground, turned, or polished surfaces.
3.6.2 All product shall be inspected ultrasonically in accordance with AMS 2630 and shall meet Class AA quality requirements as defined therein. Hot finished surfaces shall be suitably prepared prior to ultrasonic inspection.
3.6.3 Grain flow of die forgings, except in areas which contain flash-line end grain, shall follow the general contour of the forgings showing no evidence of reentrant grain flow.