Course 02 · Nitriding for Tool & Die
See all courses →Nitriding for Tool & Die
The deep dive. Twelve lessons on spec'ing, QC'ing, and reading the failure modes of nitrided tooling — gas, salt-bath, plasma, FNC.
- 015 min
Nitriding, deeper: why this course exists
The four levers that make one nitriding job different from another, and what a complete nitriding certificate documents that an incomplete one leaves out.
- 027 min
The metallurgy you actually need — Fe-N phase diagram in plain English
Epsilon vs gamma-prime, the 590°C ceiling, and what Kn = 2.5 on a vendor quote actually constrains.
- 039 min
Gas nitriding — the workhorse and its limits
How dissociating ammonia builds a case in a sealed retort, what the Floe 2-stage cycle actually does, and the difference between a controlled and uncontrolled gas nitride process.
- 049 min
Salt-bath nitriding (Tufftride / Melonite / QPQ) — fast, dirty, effective
What a 90-minute cyanate-bath FNC cycle delivers compared to a 60-hour gas retort, what QPQ's oxide step actually adds, and which dies belong in a salt pot and which do not.
- 0510 min
Plasma / ion nitriding — control, distortion, and the parts that need it
Why a 420 stainless mold cavity that gas nitride ruins comes out of a plasma cycle intact, what the four plasma levers actually do, and which parts the process is the correct call for.
- 068 min
FNC vs nitriding — stop confusing them
How carbon in the atmosphere changes the compound layer, why FNC owns stamping and powder-metal tooling, and how to tell the two processes apart on a quote and a microsection.
- 079 min
Reading a microsection — white layer, diffusion zone, and what the photo isn't telling you
How to look at a vendor's etched cross-section and microhardness traverse, what a porous compound layer means, and which case-depth definition is on the certificate.
- 088 min
Pre-nitride heat treatment — you can't nitride a soft die
Why the temper temperature has to sit above the nitride cycle by 30-50°C, why EDM without stress relief is the single most common cause of premature nitrided-tool failure, and what the print has to say before the part ships out for treatment.
- 0911 min
Application playbook — forge dies, stamping, plastic molds, gears, extrusion
Five tool classes, five different recipes: typical steel, target case depth, target compound layer, preferred process, and the failure mode each recipe is designed to defend against.
- 1011 min
Failure modes — white-layer spall, network cracking, distortion, embrittlement
Five ways a nitrided tool fails in service, how to read each one from a microsection, and when 'the nitride failed' is honestly 'the wrong recipe was specified.'
- 117 min
Writing the spec — what goes on the print
An annotated nitriding callout template a competent vendor can hit and an incompetent one will refuse, with the eight elements that turn a wish into a spec.
- 128 min
Vendor selection and QC sign-off — separating real nitriding houses from job shops
The 30-minute phone audit, the on-site signal list, the first-article QC checklist, and the small-shop exceptions that pencil out anyway.