D2 tool steel occupies a unique position in the knife world. With a carbon content of 1.4–1.6% and a chromium content of 11–13%, it sits on the border between carbon and stainless steel. It's sometimes called "semi-stainless" because its chromium content is high enough to offer moderate corrosion resistance but not the 13% minimum typically needed for true stainless classification.
D2's high hardness (58–62 HRC when properly heat treated) gives it exceptional wear resistance and edge retention — far better than steels like AUS 8 or 8Cr13MoV. This is why D2 has become extremely popular in budget-premium knives from brands like Kershaw (Bareknuckle), CIVIVI, Kizer, and many Chinese manufacturers.
The main trade-offs with D2 are toughness and sharpenability. It is more brittle than tougher steels like S35VN or CPM-3V, meaning it can chip under lateral stress or heavy prying. Sharpening D2 to a toothy working edge is achievable on most abrasives, but getting a mirror-polished edge requires diamond or CBN stones.
For EDC users who maintain their knives and don't abuse them, D2 represents exceptional value — premium-tier edge retention at mid-range prices.