Forging vs Casting: Which Process Is Right for Your Parts?

Jul 27, 2026
Tags: Professional precision metal parts forging + CNC machining + polishing, etc.Professional Precision Cnc Machining Parts

Selecting the right material is the single biggest lever on a machined part's performance, cost, and lead time. This guide breaks down the most common CNC machining materials by what actually matters on the shop floor and in the field—so you can specify with confidence instead of guessing.

Start With the Application, Not the Metal

Before naming a material, answer four questions:

  1. What loads and temperatures will the part see?

  2. Does it need corrosion or chemical resistance?

  3. What are the weight constraints?

  4. What is the target cost and volume?

The answers usually narrow the field fast.

Common CNC Metals Compared

MaterialStrengthWeightCorrosion Resist.MachinabilityTypical Use
6061 AluminumGoodVery lowGoodExcellentBrackets, enclosures
7075 AluminumHighLowModerateGoodAerospace, structural
304 StainlessGoodHighExcellentModerateFood, medical, marine
316L StainlessGoodHighBest (marine)ModerateImplants, offshore
Titanium (Gr5)Very highLowExcellentDifficultAerospace, medical
BrassModerateHighGoodExcellentFittings, EMI shields
Tool SteelVery highHighLow (needs coating)DifficultMolds, wear parts

Common CNC Plastics Compared

MaterialStrengthTemp Resist.Notes
ABSModerateLowCheap, easy
POM (Delrin)GoodModerateLow friction, stable
PCGoodModerateTransparent option
PEEKVery highHighAerospace/medical grade
PEI (Ultem)HighHighFlame-retardant

Decision Rules of Thumb

  • Lightweight + corrosion resistant → 6061 aluminum.

  • High stress + light weight → 7075 aluminum or titanium.

  • Wet, chemical, or marine → 316L stainless or titanium.

  • Biocompatible / implantable → 316L or titanium with full MTR.

  • Tight tolerances on a budget → aluminum or brass (best machinability).

  • Electrical insulation or low weight → PEEK, PEI, or POM.

Don't Forget the Finish

Material choice and finish are linked. Stainless often gets passivation; aluminum gets Type II/III anodizing; titanium may be bead-blasted. The finish affects both appearance and function, so specify it alongside the base material.

How Zhuoguan Metal Supports Material Selection

Our engineering team reviews your drawing and application, then recommends the most cost-effective material that meets performance requirements. We machine aluminum, stainless, titanium, brass, copper, tool steel, and a full range of engineering plastics, with Mill Test Reports available for every shipment.

Frequently Asked Questions

What is the easiest metal to CNC machine?

Aluminum (especially 6061) and brass offer the best machinability—faster feeds, better surface finish, lower tool wear.

Is titanium hard to machine?

It is more difficult and slower than aluminum or steel, but entirely standard for an experienced shop. Expect longer cycle times and higher cost.

Which plastic is best for precision parts?

POM (Delrin) for dimensional stability and low friction; PEEK or PEI for high-temperature or medical-grade needs.

Can you certify the material?

Yes. We provide Mill Test Reports (MTR) to ASTM and ISO standards, with full traceability for regulated industries.

Need help specifying your material?

Send your drawing—our engineers will recommend the optimal, cost-effective material.

Talk to an Engineer
ZG Metal focuses on the research and development and production of precision parts for various industries. We supply forgings and CNC machined parts using various casting processes.
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Email:gavinlee@zhuoguanmetal.com

Address: Room 805-1, Building A, Block 1, Xingzhan Plaza, No. 446, Shajing Nanhuan Road, Shatou Community, Shajing Street, Bao'an District, Shenzhen, Guangdong, China 518104