Citiraj:
Autor SlavoS
Zašto AO kamenje nije adekvatno ?
Koja je " stvar u Karbidima " ?
|
vanadium carbide tear-out during sharpening
Vanadium & chromium carbides are actually first formed in the manufacture of the alloy, before it's ever heat-treated. Subsequent heat treat can change their properties somewhat (size, hardness to some small degree), but they exist in the steel from the time of it's manufacture, formed at temperatures up around 1000°C.
Different manufacturing processes, like the powder metal (PM) process, can make a difference in how large they get and how uniformly distributed ('desegregated') they are in the manufactured steel. PM-process steels produce carbides that are typically pretty small, usually 2 - 4 microns or smaller, and they're more uniformly distributed throughout the steel, which helps it remain strong and tough overall. Non-PM processes would tend to allow the carbides to cluster together in large masses, the effect called 'carbide segregation', during manufacture. In such cases, the carbides may end up being 50 microns or larger in size. So, they'd still be there, but at potentially much larger size, which makes grinding such steels more difficult, and also can negatively alter steel properties such as toughness (resistance to breakage). As an example, the difference in ease of grinding or sharpening can be seen in comparing conventionally-manufactured 'ingot' D2 with it's huge chromium carbides (making it harder to grind easily), versus CPM-D2 and it's much smaller chromium carbides (easier grinding/machining), made by the powder-metal process.
konspirativna je tema zašto - zato
