Please understand my comments here are my understanding related to the differences between conventional and CPM process. I look forward to others corrections, updates, additions to my comments here. I believe ..., all my comments here would apply to all CPM produced steels, not just CPM Cruwear as asked by the OP.
CPM process produces a superior end result (compared to conventional steel making) by reducing/eliminating alloy segregation (clumping of alloys) during the process of solidification (turning to solid during cooling). Both are/can-be processed into ingots during manufacture. This is beneficial throughout the process of manufacture (a better steel means better grinding, better heat treatment results, better finishing, better end user performance and future sharpening because the steel is more consistent throughout. Additionally, end results will be more easily repeatable making for better consistency throughout manufacture process to end result. . More on better sharpening examples below.
With convention process the molten mix (base metal and all added alloys) are poured into an ingot mold and cooled. During the cooling process various alloys segregate, to some degree, into micro clusters of like alloys (pockets of alloys in the base metal). The poured/cooled ingots are later forged (or hot rolled) into sheet steel for stock removal process or directly into finished product.
With CPM process the molten mix (base metal and all added alloys) is processed through a small nozzle with high pressure into a spray of tiny droplets that are rapidly cooled forming what might be considered mini ingots (tiny round solids of the alloyed steel) with much more even distribution of alloys (kinda like mini BBs of alloyed steel in powder form). I have used Dippin Dots vs. traditional ice-cream analogy for illustrative purposes for others in the past (little pellets of goodness). This powdered alloyed steel can then be stored in bins for later use, including loading into forms that are then hot pressed (forged, but I believe at lower temperature than typical forging) into ingots. These resultant ingots can then be hot rolled into sheet steel for stock removal process. The grain structure of the CPM steel is much more even, producing a superior product.
When looking at cross section comparisons under a microscope it is easy to see the more even distribution of carbides in CPM steel. I will choose one alloy for an example Vanadium to hopefully illustrate how CPM is better to an end user (same would apply to any alloy in steel composition). With conventional process, the Vanadium carbides will be more segregated (clumped together) after cooling. These larger clumps can more easily fracture out larger matrix formations in grinding, sharpening and in-use reducing the longevity of cutting performance. By contrast, more evenly distributed smaller Vanadium carbides will not fracture out as easily increasing overall performance (the smaller carbides provide greater adhesion, and during grinding and sharpening will produce superior results. I will try to explain why this is using concrete as an analogy.
Lets use concrete as an example (composed of cement and aggregate aka rocks). If I make a cubic yard (3 x 3 x 3) of concrete and use one rock (say 1-foot round of single-solid aggregate vs that same rock broken into small gravel), the single rock surface are in contact with the cement will be significantly less. The higher/greater surface area of the gravel will produce a number of significant benefits in making the concrete better/stronger. The concrete produced with the gravel; there will be overall greater adhesion between the two because the surface area of adhesion is greater, it will be able to be poured & formed into much smaller areas, etc., etc. This would be analogic to what we do when we grind the cutting edge on a knife. Smaller more evenly distributed alloys/carbides will result in finer, longer lasting edges, and would also produce finer polishing for those who like polished edges.
I have read through a number of threads on various forums where folks ask about using CPM-3v to forge a tomahawk into a super-steel-hawk. IMHO these are the reasons CPM steel should not be put through traditional forging process where the steel is brought back to temperature where the alloys can redistribute themselves and create alloy segregation (why start a project with CPM steel, then undo what you paid for
?).
I have seen some really great microscopic images that have shown on some knives (non CPM) where the carbides are clustered back from the cutting edge, meaning their location effectively renders them useless from a cutting performance standard. A second knife, produced with the same batch of steel, may have carbides distributed all the way the cutting edge, meaning their location will enhance the cutting performance (the whole reason the alloys would have been specified in the first place). Other images I have seen show large matrix formations of carbides near the edge. These pockets of carbides can break off resulting large chips in the cutting edge.
Less chip-out in finer edges, stronger overall product, etc., better in every way in my mind. How much better
, subjective similar to one steel over another (everyone mileage will vary based on personal usage).
