There is no universal “best” steel for every blade. Material and heat treatment need to reflect the cutting load, wear mechanism and machine conditions.
What is being cut?
The hardness, abrasiveness, thickness and consistency of the material all matter. Plastic film, frozen meat, corrugated board and scrap steel place very different demands on an edge.
How does the blade fail?
Record whether the dominant problem is gradual wear, chipping, cracking, bending, corrosion or material build-up. Each points toward a different balance of wear resistance, toughness and surface condition.
How is the machine used?
Intermittent manual work and continuous high-speed production can require different approaches. Available cooling, cleaning, sharpening and maintenance practices should also be explained.
What can be confirmed?
Share the existing blade material marking and any known heat-treatment details. Where these are unavailable, the final choice should be agreed against the application rather than assumed from appearance alone.