C260 Brass Sheet for Stamping and Bending: What the Evidence Supports, and What to Verify on C220 and C280

Temper decides whether the part bends or cracks

On C260, cold work level sets the trade between strength and ductility. Higher cold work raises tensile strength while elongation collapses, so a hard temper chosen for strength can fail the bend that the same alloy in H02 would pass¹³.

Treat the grade decision as a temper decision and pick the temper against the bend radius and strength your part actually needs.

Is C260's documented formability enough for your bend radii and draw depth?

C260 is an alpha brass with a single-phase structure at room temperature, and the sources credit that structure for its cold-working capability¹⁸. Reported elongation runs from 23% in H02 up to 30-70% depending on temper, and the alloy is described as one of the best for deep drawing and complex forming^7,9.

For a die designer, the checkable number is the reported minimum bend radius of 1.0 times thickness for half-hard material, with springback of 5-8 degrees on a 90-degree bend¹¹.

Those are screening figures from vendor-tier sources, not a specification for your thickness and tooling, so confirm them against a forming trial before you release the die.

Tooling parameters to fix before the die is cut

Springback and blanking clearance follow from the material's strength and temper, so they are set at die design rather than corrected on the press. The reported half-hard figures below come from one vendor-tier source and should be treated as a starting point for a forming trial, not a released specification¹¹.

• ✓Set blanking clearance at 4-6% of thickness for half-hard C260.
• ✓Allow 5-8 degrees of springback on a 90-degree bend.
• ✓Set punch nose radius at 1.0 times thickness minimum.
• ✓Confirm lubrication and stamping force with the stamper — the sources give no lubrication or force data for C260.

Does the service environment rule C260 out?

C260's zinc content is the mechanism behind its dezincification and stress-corrosion-cracking susceptibility, so the environment decides whether the alloy is acceptable^10,21,22. The sources agree it performs well in indoor atmospheres, freshwater and many mildly corrosive environments^7,21.

In high-chloride, acidic or stagnant water it can dezincify, and in ammonia or under residual tensile stress it can crack^10,21,22. If your part sees any of those conditions, evaluate a dezincification-resistant brass or bronze alternative before you commit.

Confirm lead-free and RoHS status for the specific heat

C260's specified composition is 68.5-71.5% copper, zinc balance, with lead capped at 0.07% and iron at 0.05%, and the sources describe it as lead-free and RoHS-compatible^9,13,18.

RoHS exemption 6c permits up to 4% lead in some brasses, but not every alloy qualifies, so compliance has to be confirmed for the specific heat rather than assumed from the alloy name¹². Ask the mill for a test certificate covering the heat, lot and standard being supplied¹⁸.

Write the RFQ so the C220 and C280 gaps come back as figures

No source in this set carries C220 or C280 data, so every comparison against C260 is currently unproven^7,9,11,13,19. Put the questions in the RFQ and let the quotes supply the numbers.

• ✓Ask each mill for C220 and C280 composition and temper-specific tensile and elongation data.
• ✓Ask for C220 and C280 minimum bend radius and springback figures for the temper you would buy.
• ✓Ask for C260, C220 and C280 sheet price per unit weight at your thickness and temper.
• ✓Ask for stock availability and lead time for all three grades in your thickness and width.
• ✓Ask which standard each grade is certified to, and request the mill certificate with the quote.

The one figure the sources dispute: C260 half-hard elongation

Two sources give different elongation values for the same H02 temper. The gap is small, but it is the number your die designer will use to judge whether the bend is safe, so verify it against the mill certificate before locking the temper into the drawing.

What the sources do not establish

• No formability, mechanical property, composition, cost, availability or corrosion data for C220 or C280 brass in any temper.
• No relative cost data for C260, C220 or C280 sheet per unit weight or volume.
• No distributor or mill availability and lead-time data for C260, C220 or C280 sheet in specific thickness, width or temper.
• No standard specification data (ASTM B36, EN 12164) for C220 or C280, and no EN 12164 data for C260.
• No stamping force, die wear or lubrication requirement data for C260, C220 or C280.
• No corrosion test data (dezincification or SCC test results) for C260 in your specific environment, and none for C220 or C280.
• No evidence that C260 is more formable, stronger, cheaper, more corrosion-resistant or more available than C220 or C280.
• No governing standard or authoritative source in this evidence establishes a mandatory grade choice for stamping and bending.