title = "Cutting Tool Materials and Coatings"

content = """
The selection of cutting tool material and coating is one of the most important decisions affecting machining productivity, tool life, and cost per part at Ridgecrest Metalworks. Tool technology has advanced significantly, with each material class suited to specific applications.

High-speed steel (HSS) tools are tough, relatively inexpensive, and can be resharpened. M2 and M4 cobalt-alloyed HSS are standard for general use. HSS is used where toughness is paramount—taps, drills for interrupted cuts, form tools—and in situations where tool sharpness matters more than hot hardness (low-speed operations). HSS tools begin to lose hardness above 1000°F (540°C).

Cemented carbide (tungsten carbide with cobalt binder) is the dominant tool material for modern high-speed machining. Carbide is much harder and more wear-resistant than HSS and retains its hardness to higher temperatures, enabling higher cutting speeds. Standard ISO carbide grades are designated by application (P=steel, M=stainless/cast iron, K=cast iron/non-ferrous, N=non-ferrous, S=heat-resistant, H=hardened) and hardness/toughness balance. Indexable carbide inserts are the primary production tooling at Ridgecrest—when one cutting edge wears, the insert is indexed to a fresh edge. Solid carbide end mills and drills are used for smaller diameters and difficult materials.

Ceramic cutting tools (aluminum oxide, silicon nitride, SiAlON) operate at cutting speeds 3–10 times higher than carbide in cast iron and hard materials. They are brittle and require rigid setups and continuous interrupted-cut capability consideration. Ceramic inserts are used for high-speed finishing of cast iron and rough turning of superalloys.

Cubic boron nitride (CBN) is second only to diamond in hardness. CBN tools are used for hard turning (hardened steel 45–65 HRC), eliminating grinding in some applications. They maintain hot hardness at temperatures where other tools would fail.

Coatings on carbide tools dramatically extend tool life and allow higher speeds. TiN (titanium nitride) was the first widely used coating—gold-colored, reduces friction. TiCN (titanium carbonitride) adds wear resistance. TiAlN (titanium aluminum nitride) has excellent oxidation resistance for dry and high-speed machining. AlCrN coatings excel in heat-resistant superalloys. Diamond coatings are used for high-speed aluminum and composite machining.
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version = "0.0.1"
