HAP40 - Tweaking the ingredients
HAP-40 is a recent reformation of ultra-hard knife blade steel. The changes are a reduction in Chromium (typically set 12-15% moved to 3.7-4.7%) which typically is used to improve corrosiveness and replacing it with increases in Cobalt, Vanadium, Tungsten and Molybdenum - the types of materials you can find in car engines :)
HAP-40 is produced by Hitachi factory in Japan.
The make up of the ingredients is as follows: