H62 Brass: Composition, Properties, Processing and RFQ Guide
H62 Brass: Composition, Properties, Processing and RFQ Guide
H62 brass is a Chinese wrought copper-zinc alloy designation used for rod, bar, plate, strip, tube and formed components. The “62” indicates a nominal copper level near 62%, but a purchase specification requires more than that shorthand. Product form, governing standard, temper, dimensions, surface condition, inspection and intended environment all affect whether material is suitable.
This guide is written for industrial buyers, engineers and quality teams comparing H62 brass material. It explains chemistry, microstructure, product-form standards, approximate international comparisons, processing limits, corrosion risks and RFQ information. It does not approve a substitution, pressure boundary, drinking-water application, electrical rating or forming process. Final material and acceptance requirements must follow purchaser-approved documents.
What the H62 designation means
GB/T 5231-2022 is the current Chinese national standard for designations and chemical compositions of wrought copper and copper alloys. H62 is a wrought common brass grade within that system. It should not be confused with a cast-brass designation or treated as a universal international name.
The current standard identifies the complete chemical limits. The procurement summary below is useful for screening, but the purchased standard text controls acceptance. Values are mass fractions. Do not replace the standard with a supplier’s typical analysis.
| Element | H62 procurement summary | Purchasing note |
|---|---|---|
| Copper (Cu) | 60.5–63.5% | The grade name is nominal; use the specified range for acceptance. |
| Zinc (Zn) | Remainder | Zinc content follows from copper and controlled residuals. |
| Iron (Fe) | Maximum controlled by GB/T 5231 | Verify the exact current limit on the certificate. |
| Lead (Pb) | Maximum controlled; H62 is not a free-machining leaded brass | Do not substitute a leaded machining brass without approval. |
| Other residuals | Individual and total impurity limits apply | Request the full analysis when residuals matter to forming or compliance. |
The often-published summary uses maximum values of 0.15% Fe, 0.08% Pb and 0.5% total impurities, with tighter individual controls for elements such as Sb, Bi and P. Because standards can be revised and reporting conventions differ, confirm these values against GB/T 5231-2022 and the purchase order rather than copying them into a drawing without review.
Why chemistry does not define the finished properties
H62 is normally a wrought alloy. Its final strength, hardness and elongation depend strongly on product form, cold work, annealing history, section and test direction. A hard-drawn rod and an annealed sheet can meet the same chemistry designation yet behave differently in bending or machining. Therefore, an RFQ should pair GB/T 5231 chemistry with the applicable product standard and temper.
For cold-drawn rod and bar, GB/T 4423-2020 is the current Chinese national standard. Sheet, strip, tube or other forms require their own applicable standards. Mechanical values copied from one form or temper must not be presented as a universal guarantee for all H62 products.
Microstructure and the effect of zinc
Brasses are copper-zinc alloys whose phases and working response change with zinc content and thermal history. The Copper Development Association explains that lower-zinc alpha brasses are highly cold workable, while intermediate-zinc brasses can contain alpha and beta phases and tend to be easier to hot work but less cold formable. H62 lies near the 60/40 brass region, so processing condition and phase balance require attention.
Cold work raises strength and hardness while reducing remaining ductility. Annealing can restore formability by recovery and recrystallization, but an uncontrolled cycle can alter grain size, dimensions and surface condition. Buyers should specify the required temper or property range instead of asking for “H62 brass” alone.
| Condition variable | Likely influence | RFQ control |
|---|---|---|
| Cold reduction or drawing | Raises strength/hardness and reduces ductility | Temper, tensile/hardness requirement and test direction. |
| Annealing | Restores formability and changes grain structure | Delivery temper, grain-size requirement if critical and dimensional condition. |
| Rod versus sheet | Different processing route and property direction | Correct product standard, dimensions and test method. |
| Section size | Affects achievable tolerances and forming response | Nominal size, tolerance, straightness/flatness and sampling. |
H62 is not automatically equivalent to C26000 or C28000
Search results often label H62 as equivalent to UNS C27400, C28000, CuZn37, CuZn38, C2801 or another national grade. These may be approximate commercial comparisons, not automatic one-to-one equivalents. For example, the Copper Development Association lists C26000 cartridge brass with a different copper range. Matching a nominal copper percentage does not align every residual limit, temper designation, product-form requirement or mechanical property.
A substitution review should compare the complete standards and intended product form. The purchaser’s materials engineer should approve the result in writing.
| Comparison item | Why it matters | Required decision |
|---|---|---|
| Chemical ranges | Cu, Zn, Pb, Fe and residual limits may differ | Line-by-line comparison to the applicable editions. |
| Product form | Rod, sheet, strip and tube standards use different requirements | Compare the form actually purchased. |
| Temper | Temper codes and property ranges are not universal | Map condition and required tests. |
| Dimensions | Tolerances, straightness, edge and surface rules differ | Use the approved drawing and product standard. |
| Regulatory limits | Lead, restricted substances or potable-water rules may apply | Identify the applicable law and test evidence. |
Forming, machining and joining considerations
H62 can be processed by hot and cold working, but suitability depends on temper, reduction, bend radius, lubrication, tooling and part geometry. A tight bend in a hard condition may crack even when chemistry complies. If severe drawing or bending is required, state the incoming temper, minimum bend radius, grain direction and whether intermediate annealing is permitted.
H62 contains only controlled residual lead and should not be treated like a deliberately leaded free-machining brass. Machining parameters and chip control should be qualified for the delivered condition. When brazing, soldering or welding is planned, the joint designer must consider heat input, filler compatibility, zinc volatilization, cleanliness and final service. Follow applicable ventilation and occupational-safety controls; zinc-containing fumes can be hazardous.
Corrosion and environmental limits
Brass commonly performs well in many atmospheric and freshwater conditions, but it is not immune to corrosion. Copper.org identifies dezincification concerns for some brasses in stagnant acidic aqueous environments and stress-corrosion cracking in the presence of tensile stress and environments such as moist ammonia. Water chemistry, temperature, velocity, deposits, residual stress and joining method all affect risk.
Do not approve H62 for seawater, ammonia-bearing service, potable water or a regulated fluid based on a generic corrosion statement. Provide the actual medium and operating range, then obtain materials and regulatory review. If dezincification resistance is mandatory, specify an alloy and test requirement designed for that purpose rather than assuming H62 will comply.
| Environment question | Evidence to provide | Boundary |
|---|---|---|
| Water chemistry | pH, chlorides, dissolved gases, temperature and stagnation | “Water service” is not a complete corrosion definition. |
| Ammonia or amines | Concentration, humidity, temperature and tensile stress | Requires stress-corrosion review. |
| Potable-water contact | Country/market approval and extraction limits | Chemistry certificate alone does not prove legal compliance. |
| Electrical duty | Required conductivity and test method | Do not infer conductivity from grade name only. |
Dimensional and surface requirements
For rod, state shape, diameter or across-flats size, length, straightness, end condition and whether the surface is drawn, turned, ground or otherwise finished. For plate or strip, state thickness, width, flatness, coil/length condition, edge and surface class. Identify any area that will be sealed, plated, brazed, formed or used as an electrical contact.
Visual appearance is not a reliable alloy identification method. Oxide color, staining and polishing can change the surface without changing bulk grade. Use traceable material records and, where agreed, chemical verification.
Inspection and certificate requirements
| Requirement | What to specify | Possible record |
|---|---|---|
| Chemistry | GB/T 5231 edition, H62 designation, elements and sampling | Heat/lot chemical analysis certificate. |
| Mechanical properties | Product standard, temper, test method and direction | Tensile or hardness report where required. |
| Dimensions | Drawing, tolerances, straightness/flatness and sampling | Dimensional report. |
| Surface | Finish, permitted defects and protected functional areas | Visual inspection and agreed photographs if needed. |
| Traceability | Lot marking, certificate linkage and packaging labels | Receiving-verifiable identity trail. |
Common procurement mistakes
- Ordering “62 brass” without GB/T 5231, product form or temper.
- Copying typical mechanical properties from an unrelated thickness or condition.
- Calling C26000, C28000 or CuZn37 an exact equivalent without a standards comparison.
- Assuming H62 is a free-machining leaded brass.
- Approving corrosive or potable-water service without environmental/regulatory review.
- Using color or handheld screening alone as final grade acceptance.
- Omitting surface, straightness, packaging and traceability requirements.
RFQ checklist for H62 brass
- Product form: rod, bar, sheet, strip, tube or customer-machined component.
- GB/T 5231-2022 and the applicable product standard/edition.
- H62 grade, delivery temper and required mechanical properties.
- Dimensions, tolerance, straightness/flatness, length and surface finish.
- Forming, machining, plating, brazing or welding operations planned by the purchaser.
- Service medium, temperature, corrosion and regulatory constraints.
- Chemistry, mechanical, dimensional and surface inspection records.
- Lot traceability, marking, packaging, quantity and destination.
Receiving and nonconformance workflow
At receipt, compare the purchase order, packing list, material marking and certificate before mixing lots. Inspect packaging damage, corrosion, dimensions and surface condition using the agreed sampling plan. If chemistry or properties are disputed, quarantine the lot and agree the test method and representative sample location before cutting material.
Do not relabel an approximate substitute as H62. Record any deviation against the purchase order and obtain purchaser approval. Preserve certificates through machining so finished parts can remain traceable to the incoming lot.
Related H62 products and technical guidance
For drawing-based product enquiries, review the H62 copper alloy rod and H62 brass plate pages. The guide to chemistry, heat analysis and product analysis explains why a composition result must be tied to a standard and sampling method. See quality assurance and factory capability for general context.
Send specifications for review
Use the contact page to send an H62 brass RFQ. Include the applicable standard edition, product form, temper, drawing, dimensions, planned processing, service environment, inspection, quantity and destination.
Engineering boundary: This article is general materials and procurement guidance. It does not certify equivalence, corrosion resistance, legal compliance, formability, joinability or component performance. Final acceptance must follow the customer-approved specification and current standard text.
How to qualify H62 brass before production release
A useful qualification plan connects the incoming material certificate to the operation that creates the highest risk. For a turned rod component, that may be tool life, chip control, straightness and finished-surface acceptance. For a formed strip component, it may be bend direction, edge quality, minimum radius, springback and cracking after plating. The qualification coupon should come from representative production stock in the ordered temper and size, not from an unrelated laboratory sample.
Step 1: freeze the purchasing baseline
Record the governing material and product-form standards, delivery temper, nominal dimensions, tolerances, surface class and certificate requirements. If the drawing contains an international comparison, label it as an approved alternative only after the purchaser has reviewed chemistry, temper and product-form differences. A supplier should not decide equivalence from a trade-name table.
Step 2: link receiving checks to processing risks
Use traceable receiving checks appropriate to the risk. Certificate review and dimensional inspection may be sufficient for a mature, controlled application; critical forming or regulated service may require agreed verification testing. Handheld alloy screening can support identification, but its detection limits and surface sensitivity must be understood. It does not automatically replace a laboratory method or the purchase specification.
Step 3: run a representative process trial
Document tooling, lubrication, speed, reduction, heat input and inspection results. For forming, record material direction, bend radius and evidence of edge or surface cracking. For joining, qualify the exact filler, preparation, heat source and ventilation controls. For plating, confirm cleaning compatibility and adhesion. Retain the trial record with the heat or lot identity so a later process change can be distinguished from a material change.
Step 4: define release and change control
State who may approve deviations in chemistry, temper, dimensions, surface condition, mill source or processing route. A successful first-article trial does not permit silent substitution on later orders. When service includes corrosion, pressure, potable water or a regulated market, the responsible engineer must define any additional qualification and compliance evidence.