Copper, zinc, stainless and specialty metals · Lesson 2 of 4

Copper, zinc, stainless and specialty metals: materials, standards and design constraints

The ASTM designations for copper, lead-coated copper, zinc and stainless, one federal guide specification as a worked reading, the forming limits makers publish, thermal movement and expansion joints, and the contact and runoff rules.

You will be able to: Identify the standard each metal is bought to, read what a guide specification asks of it, and explain how temper, metal temperature, springback, thermal movement and runoff constrain what the shop makes.

13 min · 12 slides · 11 questions

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Slide 1 of 12

Which standard names which metal

Copper sheet for building construction is ASTM B370 (B370-22); lead-coated copper is ASTM B101 (B101-22); rolled zinc is ASTM B69 (B69-26).

Stainless plate, sheet and strip are covered by ASTM A240/A240M (the -26 edition is listed as active); UFGS 07 60 00 cites ASTM A480/A480M for its stainless.

The project spec names the standard and edition that apply.

Sources

ASTM B370-22 Standard Specification for Copper Sheet and Strip for Building Construction - ASTM International
ASTM B101-22 Standard Specification for Lead-Coated Copper Sheet and Strip for Building Construction - ASTM International
ASTM B69-26 Standard Specification for Rolled Zinc - ASTM International
ASTM A240/A240M-26 Standard Specification for Chromium and Chromium-Nickel Stainless Steel Plate, Sheet, and Strip for Pressure Vessels and for General Applications - ASTM International
UFGS 07 60 00 Flashing and Sheet Metal (Unified Facilities Guide Specifications, August 2023, Change 1 05/25) - USACE / NAVFAC / AFCEC (Whole Building Design Guide)

Glossary

Elongation: How far a test piece stretches before it breaks, as a percentage; Revere lists 45% for soft O60 copper and 30% for cold-rolled H00.
Springback: The elastic recovery of sheet after bending, so the angle opens slightly. Outokumpu calls it the major issue in bending stainless, especially high-strength steel, and over-bends the part so it lands on the angle.
Expansion joint (sheet metal): A joint that lets a continuous run of metal move with temperature; UFGS 07 60 00 spaces them no more than 40 ft apart for metals other than aluminum.
Runoff corrosion: Corrosion of a metal by water that has run off a more noble metal such as copper, without the two touching; AFS screening says never drain copper onto zinc.
2D finish: The stainless sheet finish named in UFGS 07 60 00 for flashing and sheet metal, which asks for Type 302 or 304 stainless in 2D finish, fully annealed, dead-soft temper, at least 0.64 mm (24 gauge).