Metal Stamping Materials and What to Specify Before the Quote

“Make it out of steel” can start a conversation. It cannot finish a production specification.

SanCo Buyer Guides · 6 min read

Metal stamping materials include carbon steel, stainless steel, aluminum, coated steel, copper and brass. The useful choice is the one that meets the finished part’s requirements and can be formed consistently in the proposed condition. Before comparing prices, make sure everyone is quoting the same grade, temper, thickness and finish.

SanCo’s sheet metal stamping capabilities connect that material discussion to the drawing, tooling and production requirements. Here is what to settle before the quote turns into a purchase order.

Start with what the finished part must do

Give engineering and the quoting team the operating conditions, not just the material name copied from an old print. Does the part carry a load, flex repeatedly, conduct electricity, sit outdoors or contact cleaning chemicals? Is a visible surface part of the acceptance requirement? Will the component be welded, plated or assembled against another material?

Separate mandatory requirements from preferences. If the material is fixed by an approved design or customer specification, say so. If alternatives are welcome, ask for them as separate proposals with differences identified. A buyer should not have to discover a material substitution after parts arrive.

Compare the material families without treating them as interchangeable

Material familyWhat to settle in the RFQ
Carbon steelExact grade and product specification, required mechanical condition, thickness and corrosion-protection requirements. “Cold rolled” alone leaves important details unanswered.
Stainless steelExact grade, supplied condition, finish and service environment. Include forming and cleaning requirements; the word “stainless” is not a complete specification.
AluminumAlloy plus temper, thickness and surface requirements. Identify any subsequent welding, coating or heat-treatment steps that engineering needs to evaluate.
Coated steelBase-steel requirements as well as coating designation. Specify whether the coating is supplied on the stock or applied after forming, and how exposed edges are handled.
Copper and brassAlloy, temper and required electrical or mechanical performance. For contacts and spring features, review formability alongside the finished part’s function.

This table is an RFQ checklist, not a claim that every alloy or condition is suitable for every stamping process. Have the proposed manufacturing source confirm the specific combination.

Grade and temper belong together

The alloy identifies the material chemistry; its condition also matters. The Aluminum Association explains that alloying and treatments affect aluminum properties, and maintains separate alloy and temper designation records. Do not reduce an aluminum callout to its alloy number when the approved design also specifies a temper.

For aluminum-specific bend, forming and anodizing questions, use our aluminum stamping buyer guide before releasing the tooling.

Copper-alloy strip makes the strength-versus-formability tradeoff especially clear. The Copper Development Association describes how increasing strength through cold rolling can reduce the ability to form a given bend. Material that works for a relatively flat contact may need a different review when the design adds a tight bend.

Austenitic stainless steels can offer useful formability while also work-hardening during deformation. The Nickel Institute identifies forming sequence, lubrication and surface finish as relevant to the result. Ask the stamping team how the supplied condition fits the forming sequence rather than selecting material from strength alone.

Specify thickness in dimensions and define the acceptance condition

Put the nominal thickness, units and applicable tolerance on the drawing or referenced specification. Avoid leaving the supplier to interpret a gauge callout without the material and governing convention.

Also distinguish starting-stock requirements from finished-part requirements. Identify whether a critical dimension is accepted before or after coating and which surfaces matter to assembly. If a coating is required, include its specification, masking requirements and any functional surfaces that must remain uncoated.

Ask the supplier to identify assumptions about stock thickness, coating and inspection in the quote. This makes differences visible before two apparently similar prices become two different parts.

Review bends and grain direction before releasing tooling

A bend radius that works for one alloy, temper and thickness is not a universal rule. The Copper Development Association discusses the effect of strip orientation on bend formability; ASTM B820 likewise cautions that applying copper-strip bend-test results depends on the actual forming conditions.

For the RFQ, mark critical bends and any required rolling-direction relationship. Ask whether the proposed strip layout supports them and whether trials or additional material data are needed. Any suggested drawing change should go through engineering approval.

Keep the question practical: “Can this specified material make this feature consistently, and what evidence or tryout will confirm it?”

Include the surface the customer will actually receive

Define cosmetic faces, acceptable handling marks, burr requirements and the intended finished appearance. State whether protective film is required and where it must be removed. Include cleaning, finishing and packaging in the scope so the team can review the whole route.

For a coated part, ask how forming and subsequent operations affect the required surface. For an electrical component, have engineering specify the contact-surface requirements. “Deburr and finish” is too open-ended when a particular edge or surface controls performance.

Keep substitutions and material records under control

Ask what material documentation will accompany production and what traceability your program requires. If the customer needs a particular certificate, test result or approval package, include that requirement with the RFQ.

Request written approval before changing an alloy, temper, thickness or finish outside the accepted specification. When an alternate material is proposed, have the supplier list the differences, the reason for the proposal and any needed sample or validation work.

The same discipline applies to availability. Ask about the proposed stock form, purchasing minimums and release assumptions. A low material price is not the whole purchasing decision if the program must carry excess inventory.

Send one complete material package

Before requesting a firm production quote, include:

  • Drawing and CAD with matching revision status.
  • Material grade, governing specification and required condition or temper.
  • Nominal thickness, units and applicable tolerance.
  • Critical bends, functional dimensions and any grain-direction requirements.
  • Surface, coating, burr and packaging requirements.
  • First-order quantity, release quantities and realistic annual demand.
  • Material records, traceability and inspection deliverables.
  • Whether alternatives are permitted and who approves them.

If a requirement is unresolved, label it preliminary. Ask the quote to separate confirmed scope from assumptions rather than dressing an estimate up as a settled production plan.

For a smaller program, our short-run stamping tooling guide explains how to compare the investment against realistic purchases.

Bring the print and the material callout

SanCo is family owned and operated, serving manufacturing customers since 2001. We help buyers bring the drawing, material requirements and production plan into the same sourcing conversation.

Send your stamping RFQ with the current print, material callout, quantities and timing. Include open questions so they can be addressed before tooling becomes a commitment.

Technical references