CNC Machining Materials Reference

Category	Material	ISO/ASTM Standard	Density (g/cm³)	Tensile Strength (MPa)	Key Properties	Typical Applications	Machinability Rating★★★★★
Aluminum & Alloys	6061-T6	ASTM B221 / ISO 209	2.7	310	Lightweight, corrosion-resistant, excellent machinability	Aerospace structures, electronics enclosures	★★☆
	7075-T6	ASTM B209 / ISO 209	2.81	572	High strength (near steel), but lower corrosion resistance	Aircraft frames, high-performance parts	★★★
	2024-T3	ASTM B211	2.78	470	High toughness, ideal for sheet metal	Aircraft skins, rivets	★★★☆
Steel & Alloys	Low Carbon (1018)	ASTM A108	7.87	440	Cost-effective, weldable	Shafts, gears, structural components	★★☆
	Medium Carbon (1045)	ASTM A29	7.85	585	Balanced strength and machinability	Bolts, hydraulic components	★★★
	Alloy Steel (4140)	ASTM A322	7.85	655	Wear-resistant, heat-treatable	Molds, drive shafts	★★★☆
	303 Stainless	ASTM A276	8	620	Free-machining (sulfur-added), corrosion-resistant	Medical screws, food equipment	★★☆
	316 Stainless	ASTM A276	8	580	Superior corrosion resistance (marine-grade)	Chemical piping, marine hardware	★★★★
Titanium & Alloys	Grade 2 (CP Ti)	ASTM B348	4.51	345	Biocompatible, excellent corrosion resistance	Medical implants	★★★★
Titanium & Alloys	Ti-6Al-4V (Grade 5)	ASTM F1472	4.43	930	High strength-to-weight ratio, heat-resistant	Jet engine components	★★★★☆
Copper Alloys	C36000 Brass	ASTM B16	8.5	340	Excellent machinability, electrical conductivity	Valves, electrical contacts	★★☆
Copper Alloys	C93200 Bronze	ASTM B584	8.8	310	Wear-resistant, self-lubricating	Bearings, gears	★★★
Magnesium Alloys	AZ31B	ASTM B107	1.78	260	Lightest structural metal, EMI shielding	Camera bodies, laptop casings	★★★☆
Engineering Plastics	ABS	ISO 2580-1	1.05	40	Impact-resistant, paintable	Prototypes, consumer products	★★☆
	Nylon PA66	ISO 1874	1.14	80	Wear-resistant, but hygroscopic	Gears, bearing housings	★★★
	Polycarbonate (PC)	ISO 7391	1.2	65	Transparent, impact-resistant	Protective covers, optical components	★★★
	POM (Delrin®)	ISO 9988	1.41	70	Low friction, high rigidity	Precision gears	★★★☆
High-Performance Plastics	PEEK	ASTM D6262	1.32	100	Heat-resistant (260°C), chemically inert	Medical sterilization tools	★★★★
High-Performance Plastics	PTFE (Teflon®)	ASTM D4894	2.15	30	Non-stick, chemical-proof	Seals, chemical linings	★★★★
Composites	Aluminum-CFRP	Custom	2.1	500+	Lightweight with high strength	UAV structures	★★★★☆
Composites	G10/FR4	IPC-4101	1.8	350	Electrically insulating, heat-resistant	PCB substrates	★★★★
High-Temp Alloys	Inconel 718	ASTM B637	8.2	1,300	Withstands 1000°C, creep-resistant	Turbine blades	★★★★★
High-Temp Alloys	Hastelloy C276	ASTM B575	8.89	790	Resists strong acids/alkalis	Chemical reactors	★★★★★
Exotic Metals	Tungsten (W)	ASTM B777	19.25	1,000+	Extreme melting point (3422°C)	Counterweights, radiation shielding	★★★★★