TiN (Titanium Nitride): This is a light gray or silver coating that improves wear resistance and reduces built-up edge formation. It is suitable for general-purpose machining of ferrous materials, but has low heat resistance and durability1.

AlTiN (Aluminum Titanium Nitride): This is a violet-gray coating that improves hardness, wear resistance, and heat resistance. It also reduces friction and prevents built-up edge formation. It is suitable for high-speed and high-temperature machining of cast iron, stainless steel, titanium alloys, and other hard and abrasive materials12.

AlTiN Nano (Aluminum Titanium Nitride Nano): This is a black coating that improves hardness, wear resistance, and heat resistance. It also reduces friction and prevents built-up edge formation. It is suitable for high-speed and high-temperature machining of hardened steels, tool steels, aerospace materials, and other demanding applications12.

DLC (Diamond-Like Carbon): This is a black coating that improves hardness, wear resistance, and friction reduction. It also reduces adhesion and prevents built-up edge formation. It is suitable for low-speed and low-force machining of non-ferrous materials, such as aluminum, copper, brass, bronze, etc12.

TiB2 (Titanium Diboride): This is a gray coating that improves hardness, wear resistance, and heat resistance. It also reduces friction and prevents built-up edge formation. It is suitable for high-speed and high-temperature machining of non-ferrous materials, especially aluminum alloys with high silicon content12.

These are some of the common coatings for CNC milling cutters used in mold making. However, there are many other types of coatings available with different properties and applications. You should consult the manufacturer’s catalog or website for more specific information and recommendations for your machining needs.