heat treat 1

[paul69]

i use o1 tool steel for making stamping dies they are then ht to 59-60rc. this has been very successful for me in the long term. recently some of these stamping dies have chipped heavily while being struck. this is new to us. is it the material the heat treat or what? thanks

 

[TVP]

O1 tool steel is usually specified in the range of 57-62 HRC. This creates a hard, wear resistant steel, with only moderate fracture toughness (relative to tool steels). Depending on the stress, die geometry, etc. some of these applications may require higher fracture toughness, which improves the resistance to cracking, chipping, etc.

O1 can be tempered at a higher temperature to reduce the hardness and improve fracture toughness. Alternatively, you can investigate a moderately tougher tool steel like L6 or A2. There are some powder metal tool steels from Crucible and Carpenter that offer superior toughness for a given hardness, so that wear resistance does not have to be sacrificed for toughness.

I recommend you review some of the technical data that is available on-line from the Timken Latrobe, Crucible, and Carpenter. Carpenter has a huge amount of data available for free, including technical articles on tooling selection. You can access their websites using following links:

http://www.timken.com/products/specialtysteel/engineering/tech_info/PDF_Files/badger.pdf

http://www.crucibleservice.com/upgradeChart.cfm

http://www.cartech.com

click on Technical Information then Matched Tool and Die Sets. You must register, but it is free. Also look at the Product Literature section, which has several publications on tool steels that are quite good.