What is the composition of ASTM A387 Grade 91 Chromium-Molybdenum Alloy Steel?

Published composition ranges are not available for ASTM A387 Grade 91 Chromium-Molybdenum Alloy Steel in this record. The source entry did not carry a verified composition.

What standards cover ASTM A387 Grade 91 Chromium-Molybdenum Alloy Steel?

The governing standards for ASTM A387 Grade 91 Chromium-Molybdenum Alloy Steel include ASTM A387/A387M, ASME SA-387/SA-387M, UNS K91560. Mill certificates typically call out the most specific AMS or ASTM number applicable to the product form.

How do I verify a mill certificate for ASTM A387 Grade 91 Chromium-Molybdenum Alloy Steel?

Compare each element value on the certificate against the min/max ranges in the spec table above. Paste the values into the SpecBase validator to get an automated pass/fail check.

ASTM A387 Grade 91 Chromium-Molybdenum Alloy Steel

Q: What is ASTM A387 Grade 91 Chromium-Molybdenum Alloy Steel used for?

This alloy is used in applications demanding the property set described in its family: low_alloy_steel.

UNS K91560 low_alloy_steel

Validate composition

Quick answer

ASTM A387 Grade 91 Chromium-Molybdenum Alloy Steel is a low alloy steel specified by ASTM A387/A387M, ASME SA-387/SA-387M, UNS K91560. Typical composition: .

ASTM A387 Grade 91 is a high-strength, low-alloy ferritic steel plate material specifically designed for use in welded pressure vessels and boilers for high-temperature service. It is a modified 9Cr-1Mo steel with additions of vanadium and niobium for enhanced creep resistance.

Applicable Standards

ASTM A387/A387M
ASME SA-387/SA-387M
UNS K91560

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