What H62 Brass Is
H62 is a two-phase copper-zinc alloy in the Chinese national standard series, with a nominal copper content of 62 % and zinc making up the balance. It is one of the most widely produced and most versatile of the wrought brasses: strong enough for structural and load-bearing parts, ductile enough for stamping, drawing and bending, and inexpensive relative to higher-copper grades.
In export documentation H62 is normally cross-referenced to UNS C28000, the Muntz metal composition in the ASTM and UNS systems, which is the closest standardised equivalent in the American designation scheme. Grade equivalents should always be confirmed against the composition limits rather than taken from a summary table, because suppliers in different markets apply the cross-reference loosely.
Chemical Composition
| Element | Content, % |
|---|---|
| Copper (Cu) | 60.5-63.5 |
| Zinc (Zn) | Remainder, approximately 36.5-39.5 |
| Lead (Pb) | 0.08 max |
| Iron (Fe) | 0.15 max |
| Total impurities | 0.5 max |
The narrow copper range is what keeps the strength and forming behaviour consistent. A heat at the low end of the copper range is slightly stronger and less ductile than one at the high end, so the analysis should be checked when the material is destined for a difficult forming operation.
Tensile Strength and Temper
Tensile strength in H62 brass is controlled by temper rather than by chemistry. Cold reduction raises strength and hardness while reducing elongation, so a single grade covers a wide band of mechanical properties.
| Condition | Tensile strength | Elongation | Typical use |
|---|---|---|---|
| Soft, annealed, M | Lowest strength in the range | Up to 45 % | Severe drawing, bending and deep forming |
| Half hard, H02 | Intermediate | Intermediate | General stamping and bending |
| Hard, H04 | 330 MPa minimum | 10 % minimum | Stamped terminals, profiles, trims |
| Higher cold worked tempers | Up to approximately 600 MPa | Low | Spring elements and stiff structural parts |
The commonly quoted figures for the grade are a tensile strength of at least 330 MPa with elongation of at least 10 % in the hard state, rising to approximately 600 MPa in the most heavily cold-worked tempers, and Brinell hardness in the range of 80-110 HB depending on condition. Tensile strength well above 600 MPa should not be expected from wrought H62: grades that require it are normally produced by alloying additions or by different processing routes. Annealing to remove work hardening is carried out in the range of roughly 550-650 °C.
Physical Properties
| Property | Value |
|---|---|
| Density | 8.43-8.47 g/cm³ |
| Melting range | Approximately 905-930 °C |
| Thermal conductivity | 115-120 W/(m·K) |
| Electrical conductivity | Approximately 28 % IACS |
| Mean coefficient of thermal expansion | 20.6 × 10-6 per °C, 20-300 °C |
Electrical and thermal conductivity are consistent with one another for this alloy: an electrical conductivity near 28 % IACS corresponds to a thermal conductivity of approximately 115-120 W/(m·K). Where a data sheet quotes conductivity values that do not match this relationship, the figures should be re-checked before they are used in a heat-transfer calculation.
Applications
Architectural trim, profiles and decorative hardware, where the golden colour and outdoor corrosion resistance are valued
Electrical terminals, connectors and contacts that are stamped or formed rather than machined
Plumbing fittings, valve parts and general hardware
Heat exchanger and radiator components, where the alloy's thermal conductivity is adequate for the duty
Ammunition cases and similar deep-drawn products
Fasteners, eyelets and small pressed parts produced on high-speed presses
How H62 Compares with Other Brasses
H62 sits in the middle of the wrought brass range and is best understood by comparing it with its neighbours.
H59 contains less copper and more zinc, so it is stronger and cheaper but noticeably less ductile. It is used where strength matters more than formability.
H65 and H70 contain progressively more copper, so they are more ductile, easier to cold work and more corrosion resistant, at a higher cost.
Free-cutting brasses contain lead and machine far more easily, but their cold workability is much lower, so they cannot be substituted where the part is drawn or heavily formed.
For applications that combine moderate strength with good formability, H62 remains the most economical compromise. Where the finished part is machined rather than formed, a leaded brass will usually reduce cost per piece. Where the service environment is stagnant sea water, a dezincification-resistant brass or a copper-nickel alloy should be selected in preference to standard H62.
FAQ
Q: What is the tensile strength of H62 brass?
It depends on temper. Hard temper material is specified with a minimum tensile strength of 330 MPa and elongation of at least 10 %, while the most heavily cold-worked tempers reach approximately 600 MPa. Soft annealed material has the lowest strength and the highest elongation.
Q: What is the chemical composition of H62 brass?
H62 contains 60.5-63.5 % copper with zinc as the remainder, lead limited to 0.08 %, iron limited to 0.15 %, and total impurities not exceeding 0.5 %.
Q: What is the equivalent grade of H62 brass?
H62 is normally cross-referenced to UNS C28000, known as Muntz metal, in the ASTM and UNS designation systems. The cross-reference should be verified against composition limits because different markets apply it with different tolerances.
Q: How hard is H62 brass?
Brinell hardness is normally in the range of 80-110 HB, with the higher values in the cold-worked tempers and the lower values in the annealed condition.
Q: Can H62 brass be machined?
It machines reasonably well, better than many other brass alloys, which allows efficient production of formed and lightly machined parts. It is not, however, a free-cutting grade, so components that are primarily turned or milled are usually made from a leaded brass instead.
Q: Is H62 brass resistant to sea water?
It has good general corrosion resistance, including in fresh water and in many industrial atmospheres. For long exposure to stagnant sea water or to water with high chloride content, a dezincification-resistant brass or a copper-nickel alloy should be selected instead.
