FAQs

Is multiple tempering really necessary when heat treating tool steels?

Yes, double or triple tempering will eliminate the retained austenite that remains upon quenching. Tool steels can have up to 25% retained austenite after quenching and must be multiple tempered to eliminate this.

When is the best time to do a cryogenic treatment?

We recommend to perform the cryogenic process between the first and second temper.

Can you weld CPM steels?

We don't recommend welding our CPM grades, but we know that our customers do it from time to time. We have put together some guidlines for welding in the Tool Steel and Specialty Alloy Selector. You must be aware that the weld area will not have the same properties at the base material. The carbides and grain structure will be courser in the weld area due to the slower solidification rate when welding.

Can I successfully titanium nitride coat CPM materials?

Yes, CPM materials are great substrates for PVD coatings due to their higher tempering temperatures, uniform microstructure, and good stability after heat treatment. Our CPM steels are multiple tempered at 1000 F or higher and most PVD coatings like TiN, TiCN, TiAlN, etc. are applied around approximately 950 F. In doing so, the PVD coating process will not reduce the hardness. Grades like A2, D2, or S7 generally are not PVD coated since they have lower tempering temperatures and will lose hardness after coating.

What factors influence the wear resistance of tool steels?

The hardness influences the wear resistance somewhat, but the alloying elements chromium, vanadium, tungsten and molybdenum form hard carbide particles in tool steel when combined with carbon. The amount and type of carbides influence the wear resistance.

What are the benefits of CPM tool steels over conventionally produced tools steels?

Conventionally produced high alloy steels are prone to alloy segregation during solidification. Regardless of the amount of subsequent mill processing, non-uniform clusters of carbides persist as remnants of the as-cast microstructure. The alloy segregation can detrimentally affect tool fabrication and performance. CPM steels are HIP consolidated from very small powder particles, each having uniform composition and distribution of fine carbides. Because there is no alloy segregation in the powder particles themselves, there is no alloy segregation in the resulting compact or ingot. The uniform distribution of fine carbides also prevents grain growth, so the resulting microstrucure is fine grained. The advantages of CPM material are; higher alloy grades available, improved wear resistance, improved toughness, consistent tool performance, and better grindability.

What do the various alloying elements in tool steel do?

Click here to view the Alloying Elements PDF