Alloy Grade UNS: HH TYPE II –  Scaling Resistance at High Temperature

  • Overview

    HH Type II is a high-temperature alloy that demands precise compositional control to achieve its desired properties. This alloy is carefully balanced to contain sufficient chromium for exceptional scaling resistance at elevated temperatures, making it suitable for applications where oxidation resistance is critical. Its sensitivity to composition ensures that the alloy maintains its structural integrity and resists degradation even under prolonged exposure to high temperatures. With a service limit of 980 degrees Celsius (1800 degrees Fahrenheit), HH Type II offers reliable performance in demanding environments where precise control of its composition is essential for optimal performance.

  • Typical Uses

    Convection furnace components, grate bars, rabble arms, radiant tubes, refractory support hardware.

  • MetalTek Grade

    MTEK 25-12 TYPE II

  • Poured At:

    Carondelet Division, Sandusky International Division, Wisconsin Centrifugal Division, Wisconsin Investcast Division

Similar Specifications

Cast UNS: J93303

Cast Grade: HH TYPE II

Cast ASTM: A447

Typical Chemical Composition (% by wt.)

Aluminum: n/a

Carbon: 0.20-0.45

Chromium: 23-28

Manganese: 2.5

Iron: n/a

Copper: n/a

Nickel: 10.0-14.0

Lead: n/a

Tin: n/a

Silicon: 1.75

Zinc: n/a

Other: N 0.20 MAX

Minimum Mechanical Properties

Tensile, ksi

0

Tensile, MPa

0

Calculated PREn (Minimum)

0

Elongation

0%

Heat Treatment: Not Heat Treated

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