Description
HY Co25 Material grades and equivalents：UNS R30605 (Stellite 25)
HY Co25 is tungsten strengthened cobalt-chromium alloy is the cast version of the wrought alloy L605. A special
low carbon material has been found to have exceptional thermal fatigue resistance and is useful for tools to
work hot steel. The alloy also resists hot metal on metal wear.
HY Co25 is resistant to oxidation and carburization up to 1900°F. The alloy resists wet chlorine at
ambient temperatures and is resistant to nitric and hydrochloric acids under certain conditions. Exposure
testing is recommended to verify performance.
HY Co25 forms a protective oxide film during hot metal-on-metal wear which prevents metal transfer and damage due to adhesion. The alloy is resistant to thermal cracking and surface fatigue. Since the micro- structure is relatively free of carbide reinforcement, it is not recommended for low stress or low angle particle erosion service.
Carbide tools allow a variety of conventional machining operations. Use positive rake angle to avoid burnishing since the alloy work hardens readily. Sharp tools and coolant are recommended for drilling.
UNS R30605 (Stellite 25) Chemical composition:
Co |
Cr |
W |
C |
Ni |
Mo |
Fe |
Si |
Other |
Bal. |
20 |
14 |
0.1 |
10 |
<1.0 |
<3.0 |
<1.0 |
<0.5 |
UNS R30605 (Stellite 25) Mechanical properties:
ASME/AWS |
Hardness(HRC) |
– |
20-45 |
Characteristic as below：
HY Co25（UNS R30605/Stellite 25 ）is resistant to oxidation and carburization up to 1900°F. The alloy resists wet chlorine at ambient temperatures and is resistant to nitric and hydrochloric acids under certain conditions. Exposure testing is recommended to verify performance.
Processing conditions and application:
Metal working tools where a combination of metal-on-metal wear, thermal fatigue and hot corrosion resistanceare required, such as piercing points, forming tools, and extrusion dies. Also used for furnace hardware.
