Tool steel is rarely chosen because it is easy. It is chosen because the end part needs to survive repeated contact, abrasion, loading, or production wear without losing function too quickly. That makes it especially relevant for tooling, fixture hardware, and industrial replacement parts.
The most important early question is whether the part should be machined soft and heat-treated later, or machined closer to final hardness with a more conservative process plan. That decision affects cost, timing, and tolerance strategy.
Tool steel machining costs typically run 2–5× higher than aluminum on the same geometry, driven by slower cutting speeds, higher tool wear, and the frequent need for post-machining heat treatment and grinding. The investment pays off in applications where a softer material would require replacement every few hundred cycles — a hardened D2 wear plate, for example, can outlast mild steel by an order of magnitude in abrasive contact service.
