title = "PVD and CVD Hard Coatings for Tooling"

content = """
Physical Vapor Deposition (PVD) and Chemical Vapor Deposition (CVD) are vacuum-based processes that deposit thin, extremely hard ceramic coatings on cutting tools, forming tools, and precision wear components. At Ridgecrest Metalworks, PVD- and CVD-coated tooling is procured from specialist suppliers; understanding coating properties guides correct tool selection and care.

PVD coatings are deposited at relatively low temperatures (180–500 °C) through evaporation or sputtering of solid source material (target) in a reactive atmosphere. Common PVD coatings include:
- TiN (titanium nitride): Gold color, hardness 2200 HV, general-purpose cutting and forming
- TiCN (titanium carbonitride): Grey-violet, hardness 3000 HV, improved wear resistance for tough materials
- TiAlN (titanium aluminum nitride): Dark violet to black, hardness 3000–3300 HV, excellent hot hardness for high-speed dry machining
- AlCrN (aluminum chromium nitride): High oxidation resistance up to 1100 °C; preferred for hot forming and die casting tools
- CrN (chromium nitride): Silver-grey, used for forming and stamping tools on sticky or abrasive materials

CVD coatings are deposited at higher temperatures (900–1050 °C), limiting their use to cemented carbide substrates that tolerate these temperatures. CVD produces thicker coatings (8–20 µm vs. 2–5 µm for PVD) with excellent adhesion and is used primarily on carbide indexable inserts for heavy roughing and interrupted cuts. CVD multi-layer coatings typically include TiN / TiCN / Al₂O₃ combinations.

At Ridgecrest, PVD-coated tooling is identified by color and coating label on the tool holder or insert pocket card. Tool life data is recorded to track performance by coating type and application. When comparing two coating options for a new operation, trial cuts are run with production material and cycle time and tool wear are monitored.

Regrinding and recoating: worn solid carbide end mills and drills can be reground and recoated by specialist services. A maximum of 3–4 regrind cycles is practical before the tool geometry is compromised beyond usable tolerance. Recoated tools are re-measured for diameter and cutting-edge geometry before returning to production.

Storage of coated tools requires clean dry conditions. Stacking coated tools without separation damages cutting edges and the coating. Dedicated foam-lined tool cassettes or board racks are used for storage and transport to prevent edge chipping and coating delamination.
"""

version = "0.0.1"
