Perhaps I am not totally understanding the "abrasive" wear environment in your application. You are currently using a 400-series stainless steel heat treated to 55-60 HRC. This leads me to believe it is the alloy commonly known as 440C, as it is the most commonyl used grade with substantial carbon content for high hardness/hardenability. If this type of alloy is not providing adequate wear resistance, then I believe you have a serious problem, that may not be easily solved.
For instance, you mention the Nitronic types of stainless steel. These alloys are very good in certain types of wear applications, but without additional information (of the type I mentioned in my previous email), it is difficult to make a positive recommendation. First, they are not heat-treatable, so the hardness is only going to be in the range of 30 HRC, not 55-60 HRC. If high hardness is a requirement for this application, then I would not recommend the Nitronic stainless steels.
I cannot see how titanium would be suitable for this application, for the same reasons I just mentioned. The strength and wear resistance of titanium and its alloys will be roughly similar to high strength austenitic stainless steels like the Nitronics or 201/301. Cemented carbides (such as tungsten carbide in a cobalt matrix) may very well be better suited to this application, since they will have superior hardness and wear resistance. However, other things like fracture toughness, method of fabrication, etc. need to be considered.
The concern about metal loss into the product seems odd considering that the current application is being "chewed" up, although having bits of carbide floating around in a cheese food product doesn't sound very appealing. Considering the lack of details you have provided, I would investigate one of the following options:
1. Alloy steel instead of 400 series stainless, heat treated to appropriate range (I don't know what this would be), which is subsequently nitrided. The nitrided layer would provide a certain amount of hardness and corrosion protection, which may or may not be adequate for your application. Timken Latrobe is the maker of the standard grade known as Nitralloy. You can obtain more information from their website:
2. Apparently I am not as current in my high hardness stainless steels as I should be. While looking at Timken Latrobe's website site, I noticed several grades under the section "knife steels" which they claim to be superior to 440C. You may want to check out Sandvik as well-- they make stainless and alloy steels for high wear applications (knives, saws, cutting tools, etc.). Sandvik's website is
3. Consider using tool steel instead of stainless steel, and then treat the surface for corrosion protection. Hard chromium plating may be an option, similar to chrome plating of tool steel plastic injection molds. Places to look for more information would be Timken Latrobe, Carpenter (
and Crucible (
There are many other high hardness, high wear resistance coatings to consider like titanium nitride (TiN), titanium carbonitride (TiCN), etc. One place to look for more information on these types of coatings is Balzers Inc.:
These are standard combinations of base material (tool steel, carbide, etc.) and coating (TiN, TiCN, etc.) used for cutting tools (Sandvik, Valenite, Iscar, etc.).
Good luck with your project.
