These are Chinese produced steels that recently started showing up in Chinese made knives. 9Cr is the top end of the series and is quite good, as good or better than AUS-8. Type 8Cr, the more common formulation, is not quite as good as AUS-8, a little more corrosion-prone, and not quite as hard. It is very cheap though, and when ground appropriately it can be a real winner from a value standpoint.
*Cr*MoV Steel Knife Blades