Brass Grades H59–H68 Explained: A Selection Guide
Quick Summary
Brass grades H59–H68 differ by copper content — H59 holds 57–60% copper, H62 60.5–63.5%, H65 63.5–68% and H68 66.5–70%, with zinc making up the balance — and the copper number is the selection dial: more copper buys ductility and corrosion resistance, less copper buys hardness and machinability at l…
Brass grades H59–H68 differ by copper content — H59 holds 57–60% copper, H62 60.5–63.5%, H65 63.5–68% and H68 66.5–70%, with zinc making up the balance — and the copper number is the selection dial: more copper buys ductility and corrosion resistance, less copper buys hardness and machinability at lower cost. Pick H59/H62 for machined and structural parts, H65 for strip forming, and H68 for deep drawing. Match the grade to the forming severity before comparing prices, because the cheapest brass that cracks on the press is the most expensive brass you can buy.
The H-series naming comes from the Chinese GB standard ("H" for huángtóng, brass), and the number is the nominal copper percentage. The grades look interchangeable in a price list; on the press they are not. Here is how they differ and where each earns its place.
The Grade Ladder
| Grade | Copper | Balance | Character | Typical forms |
|---|---|---|---|---|
| H59 | 57–60% | Zinc | Hardest, free-machining variants | Tube, free-cutting bar |
| H62 | 60.5–63.5% | Zinc | General purpose, good strength | Plate, rod, tube |
| H65 | 63.5–68% | Zinc | Balanced forming and strength | Strip, small tube |
| H68 | 66.5–70% | Zinc | Most ductile, deep-drawing grade | Band, deep-drawn parts |
The trade is straightforward: copper is what makes brass soft, ductile and corrosion-tolerant; zinc is what makes it harder and cheaper. Every step down the ladder trades formability for cost.
Tempers: The Second Selection Dial
The same grade behaves differently by temper, and the H-numbers describe how much cold work the material has taken:
- O (annealed) — softest, maximum ductility, for severe forming and deep draws
- H01–H02 (quarter to half hard) — the forming range: retains enough ductility for bending while gaining stiffness
- H04–H06 (hard to extra hard) — spring-like stiffness for strips that must hold shape; forming headroom is limited
- H08 (spring hard) — maximum stiffness, effectively for flat applications only
A practical example from our own range: H65 strip in H04 holds a stamped contact shape firmly, while the same alloy in O temper would spring back and lose tolerance. Temper is not a shipping detail — it is half the specification.
Matching the Grade to the Job
- Deep drawing and severe forming → H68. Highest copper content means the best elongation; it is the standard choice for drawn shells and deep-drawn bands. Our H68 brass band for deep drawing is rolled specifically for this work.
- Strip forming, stamping, general cold work → H65. The balanced middle grade — enough ductility for progressive dies, enough hardness to hold shape. Supplied as H65 brass strip in 10–300 mm widths, H04/H06 tempers.
- Machined parts, structural sections → H62. The all-rounder; plate in 500–2000 mm widths for engraved and structural plates (H62 yellow brass plate).
- Free-machining rod work → H59. The low-copper end machines fast with clean chip breaking; supplied as H59 free-cutting brass round bar in 6–150 mm diameters, and as H59 brass tube in annealed or light-drawn temper.
The 200-Series Analogy (Worth Knowing)
Brass has its own version of the 201-for-304 substitution trap: low-copper brass sold into a high-formability application. The part does not fail immediately — it fails on the third draw, when the work-hardening that H59 tolerates poorly finally cracks the shell. If a quote is far below the copper-content ladder implies, ask for the chemistry on the certificate; a two-minute check saves a production run. Grade comparison discipline is the same muscle as picking structural steel — our Q235B vs Q345B breakdown shows the same "match the grade to the load, not to the price" logic in carbon steel.
Corrosion and Service Notes
All four grades handle water and indoor atmospheres well. Dezincification — zinc leaching out and leaving porous copper — becomes the concern in hot, chloride-rich water; the higher-copper grades (H68, H65) resist it better, and for aggressive water a cupro-nickel or tin-brass should be quoted instead. Ammonia environments attack brass of any grade. If the service environment includes either, say so at inquiry stage.
Two more service notes that buyers raise late in the process. First, stress-corrosion cracking: brass under sustained tensile stress in ammonia-bearing atmospheres (fertilizer plants, some animal-housing ventilation) cracks along grain boundaries regardless of copper content — stress-relief annealing after forming removes the risk. Second, joinery: brass brazes and solders easily, but the low-copper grades are the more forgiving base for brazed assemblies; if the part is brazed, tell the mill, because the temper choice interacts with braze temperatures.
Sizing and Supply
Yuze Metal Limited carries the H59–H68 range in tube, bar, plate, strip and band, with tempers from annealed (O) through half-hard (H04), cut to size with material certificates per shipment. Tell us the forming severity and the part geometry rather than just the grade — sometimes the right answer is one grade softer than the drawing says, and that conversation is cheaper than a cracked first article.
Write to us at info@yuzemetal.com or message us on WhatsApp; we reply fast.
