Alloy performance: How cold is too cold?

Comparing alloy performance at low temperatures

 
John H. in Wisconsin asks:

I am looking at a track shoe application and curious what data you have for low temperature charpies. Would you be so kind to share this? The idea being explored is how properties in the casting will compare to 8630… Thank you!

Answered by David Havel, P.E., Product Engineering Manager:

John, while Columbia has not performed many if any low temperature tests on manganese steel, this material is known for retaining its high toughness level even at very low temperatures. Sometimes this material is even used in cryogenic applications.

8630 is also a good alloy but does have somewhat limited through hardenability, so depending on what section thicknesses are involved this alloy can be degraded from laboratory test values. Track work castings can be very large or fairly small. Manganese steels have been used for track work castings for many years.

8630 does leave some room for improvement in track work castings. Due to this, many manufacturers (including us) have made trackwork castings from alloy steels. These materials typically work very well, but if something goes wrong they are more likely to fail in catastrophic manner. Manganese on the other hand typically does not fail in this way.