• Brass is an alloy composed of copper and zinc. Brass composed of copper and zinc is called ordinary brass, while multiple alloys composed of two or more elements are called special brass. Brass has strong wear resistance and is often used to manufacture valves, water pipes, connecting pipes for air conditioning units and radiators.

• Brass is an alloy composed of copper and zinc. Brass composed of copper and zinc is called ordinary brass, while multiple alloys composed of two or more elements are called special brass. Brass has strong wear resistance and is often used to manufacture valves, water pipes, connecting pipes for air conditioning units and radiators.

• Room temperature tissue

Ordinary brass is a copper zinc binary alloy with a wide range of zinc content variations, resulting in significant differences in its room temperature microstructure. According to the Cu Zn binary state diagram (Figure 6), there are three types of room temperature microstructures of brass: brass with a zinc content of less than 35%, whose microstructure at room temperature is composed of a single-phase alpha solid solution, is called alpha brass; Brass with a zinc content ranging from 36% to 46%, whose microstructure at room temperature consists of (α+β) two phases, is called (α+β) brass (two-phase brass); Brass with a zinc content exceeding 46% to 50%, whose microstructure at room temperature is composed only of the β phase, is called β brass.

• Folding pressure processing performance

Alpha single-phase brass (from H96 to H65) has good plasticity and can withstand hot and cold processing. However, alpha single-phase brass is prone to medium temperature brittleness during hot processing such as forging, and its specific temperature range varies with the Zn content, generally between 200~700 ℃. Therefore, the temperature during hot processing should be higher than 700 ℃. The main reason for the formation of the mid temperature brittle zone in single-phase alpha brass is the presence of two ordered compounds, Cu3Zn and Cu9Zn, in the alpha phase region of the Cu Zn alloy system. When heated at medium to low temperatures, the ordered transformation occurs, causing the alloy to become brittle; In addition, there are trace amounts of harmful impurities such as lead and bismuth in the alloy, which form low melting point eutectic films with copper and are distributed at grain boundaries, resulting in intergranular fracture during hot processing. Practice has shown that adding trace amounts of cerium can effectively eliminate medium temperature brittleness.

Two phase brass (from H63 to H59), in addition to the highly plastic alpha phase, also exhibits a beta solid solution based on the electronic compound CuZn in the alloy structure. The β phase has high plasticity at high temperatures, while the β 'phase (ordered solid solution) at low temperatures has hard and brittle properties. Therefore, (α+β) brass should be forged in the hot state. β brass with a zinc content greater than 46%~50% cannot be pressure processed due to its hard and brittle properties.