CNC Materials Buyer Guide

Materials

Not a catalog dump — a selection guide. Match strength, corrosion, weight, cost, temperature, wear, electrical needs, and compliance to a material family (and when plastics beat metals). Then open a category page or send the drawing for a stock-or-custom recommendation.

Request a Quotation Start with your requirement

Step 1

Name the job, not just the alloy

Load, environment, weight budget, temperature, insulation, cosmetics, or food/medical contact — pick the drivers first.

Step 2

Metal or plastic?

Metals for high load, heat, and wear. Engineering plastics when you need light weight, insulation, chemical resistance, or lower cost on non-structural parts.

Step 3

Family → grade → quote

Land on a family below, open the category or plastic grade page, then share temper/grade with the drawing — we machine from stock bar/plate and common custom blanks.

Start with your requirement

Each path points to a practical first family for mid/small-batch CNC parts. Final grade depends on drawing, finish, and supply — treat these as guided starting points, not certifications.

Light + strong

Need strength without the weight?

Start with aluminum. For higher specific strength or corrosive duty, consider titanium. Ultra-light housings: magnesium.

Wet / corrosive

Moisture, washdown, or outdoor exposure?

Default to stainless steel. Aggressive chemistry or seawater-class duty may push toward nickel alloys or chemical-resistant plastics such as PTFE / PVDF.

Tight budget structural

Strong, common, and cost-sensitive?

Use carbon steel for general structural and mechanical parts. Step up to alloy steel when heat treat or higher strength is required — plan for coating if corrosion is a factor.

Insulating / chemical / light

When plastics beat metals

Choose engineering plastics for electrical insulation, low weight, chemical contact, or quieter sliding parts. Common starts: POM, nylon, PC, PEEK.

High temp / wear

Heat, abrasion, or tooling duty?

Tool steel for dies, fixtures, and hard wear parts; nickel alloys for sustained high temperature. On the plastic side, PEEK, PEI, or PAI for elevated heat with lower density.

Electrical / thermal

Conductivity or insulation?

Conductors: copper (and free-cutting brass for fittings). Heat sinks and light conductive structures: aluminum. Need dielectric? Plastics such as POM, PTFE, or FR4/G10 laminates.

Medical / food contact

Cleanability and compliant grades

Common metal path: stainless. Plastic path: food-contact or medical-oriented grades in POM, PEEK, UHMWPE, or PC — confirm resin certs with your drawing. We support ISO 13485 workflows where required; share the standard early.

Cosmetics / customer-facing

Looks, feel, and finish

Aluminum (anodize-ready), stainless, brass, and acrylic/PC plastics take finish well. Call out cosmetic faces on the drawing — material choice should match the finishing route, not fight it.

Machinability / lead time

Fast to cut, easy to stock

Aluminum, brass, mild carbon steel, POM, and nylon usually machine cleanly from common stock. Hardened tool steel, titanium, nickel alloys, and filled PEEK need more cycle time — still routine for us, but plan schedule and tooling accordingly.

Metal or plastic — a quick compare

Use this matrix to shortlist a path, then open the family pages. Values are relative for typical CNC parts, not lab datasheets.

Driver	Usually metals	Usually plastics
Strength / stiffness	Steel, titanium, aluminum for most load-bearing frames and shafts	Only light loads unless using filled PEEK / GFN — metals usually win
Weight	Aluminum, magnesium, titanium	Most engineering plastics — lowest mass for covers, jigs, fluid parts
Corrosion / chemicals	Stainless, nickel alloys	PTFE, PVDF, PP, PE — often better than steel in acids/solvents
Temperature	Steels, nickel alloys, titanium	PEEK / PEI / PAI for elevated heat; commodity plastics for ambient
Wear / sliding	Tool steel, bronze, hardened alloys	POM, UHMWPE, PTFE, PAI — low friction without lubrication in many cases
Electrical	Copper / brass conductors; aluminum ground paths	Insulators and housings — POM, PC, PTFE, FR4/G10
Cost & machinability	Carbon steel & aluminum stock are efficient; exotic alloys cost more	POM / nylon / ABS often cheaper per part; PEEK stock is premium

Browse by material family

Metals stay at category level. Plastics list common machinable grades — same pattern as our CNC hub — with links to pages that already exist on the site.

Aluminum

Best first pick for light + stiff prototypes and production housings.

Choose when: weight, machinability, anodize finish

Stainless Steel

Corrosion-resistant shafts, fittings, and washdown-facing parts.

Choose when: wet, food-adjacent, outdoor

Carbon Steel

Budget structural and mechanical components from common stock.

Choose when: cost + strength; add coating if wet

Alloy Steel

Higher strength and heat-treatable grades for demanding loads.

Choose when: carbon steel is not enough

Tool Steel

Wear-resistant tooling, dies, and high-hardness components.

Choose when: abrasion, fixtures, long wear life

Titanium

High strength-to-weight for corrosive or weight-critical duty — not only aerospace.

Choose when: aluminum is light but not strong/corrosion enough

Brass

Free-cutting fittings, valves, and decorative hardware.

Choose when: machinability + moderate conductivity

Copper

Electrical and thermal conductivity parts from bar and plate.

Choose when: bus bars, heat paths, RF/electrical

Bronze

Bearing and wear alloys when you need metal-on-metal durability.

Choose when: bushings, wear pads

Nickel Alloys

High-temperature and severe corrosion service beyond stainless.

Choose when: heat + chemistry; expect longer cycles

Magnesium

Ultra-light structural pieces when every gram counts.

Choose when: lighter than aluminum is mandatory

Zinc

Selected zinc alloy components from stock or near-net blanks.

Choose when: specified zinc alloy on the drawing

Cast Iron

Stable, damping-friendly iron for bases, housings, and fixtures.

Choose when: vibration damping and stiffness

Engineering Plastics CNC machining materials

Engineering Plastics Hub

Insulating, chemical, and light-duty parts — open the plastics tab for named grades.

Choose when: metal is overkill or wrong for insulation/chemistry

If you need…	First look at…	Open
Light + strong	Aluminum → titanium / magnesium	Aluminum
Wet / corrosive	Stainless → nickel / PTFE / PVDF	Stainless
Tight budget structural	Carbon steel → alloy steel	Carbon steel
Insulating / chemical / light	POM, nylon, PC, PP, PTFE	Plastics hub
High temp / wear	Tool steel, nickel, PEEK / PEI / PAI	Tool steel
Electrical conductivity	Copper, brass, aluminum	Copper
Electrical insulation	POM, PTFE, FR4, G10	POM
Medical / food-oriented	Stainless + certified plastic grades	Stainless
Bearing / sliding wear	Bronze, tool steel, POM, UHMWPE, PTFE	Bronze

Unsure which material fits the drawing?

Send the print, environment notes, and quantity to YJCNC. We machine common stock metals and plastics and will suggest a practical family — not an aerospace-only shortlist.

Request a Quote

Contact YJCNC

Tell us about your material, drawing, tolerance, and quantity. Our team will respond with a clear next step for your CNC machining project.

Phone:
Email: info@yjcncmachining.com
WhatsApp:
Address: Yabian Community, Shajing Street, Baoan District, Shenzhen, China