Metal dust cover for speakers
Represents a common brass belt with an average copper content of 62%, where the "H" is the pinyin initial letter of the Chinese character "yellow", and has no other meaning.
62 the average content of copper element; The copper alloy with other elements added on the basis of ordinary brass is called special brass, which is still represented by "H", followed by the chemical symbol and average composition of other added elements, such as H62 for copper content of 60.5% ~ 63.5%, the margin for zinc content; HAl59-3-2 indicates that its copper content is 57%-60%, aluminum content is 2.5%-3.5%, nickel content is 2%-3% and the rest is zinc content. Brass is divided into ordinary brass, special brass and cast brass three kinds. Cast brass begins with ZCu followed by other elements of the symbol and its average content.
Copper (Cu) : 60.5~63.5%
Iron (Fe) : ≤ 0.15%
Lead (Pb) : ≤ 0.08%
Antimony (Sb) : ≤0.005%
Bismuth (Bi) : ≤0.002%
Phosphorus (P) : ≤0.01%
Zinc (Zn) : Allowance
Sum of impurities: ≤0.5%
Properties of materials
Common brass has good mechanical properties, good plasticity in hot state and cold state, good machinability, easy brazing and welding, corrosion resistance, but easy to produce corrosion rupture. In addition the price is cheap, is widely used in a common brass variety. H62 (i.e., four-six brass). The β phase is much harder than the α phase at room temperature, so it can be used in parts with higher loads. α+β two-phase brass can be hot worked above 600℃. α+β two-phase brass microstructure: α is bright white solid solution, β is CuZn-based ordered solid solution. Inhibition effect of strong electric field on cavity of H62 brass during high temperature deformation.
The stability of nickel layer in the air is very high, because nickel metal has a strong passivation ability, on the surface can quickly generate an extremely thin passivation film, can resist the corrosion of atmosphere, alkali and some acids; With excellent polishing performance, can keep its luster in the atmosphere for a long time, often used for decoration; The hardness of the nickel coating is relatively high, which can improve the wear resistance of the product surface. Environment-friendly electroless nickel plating water of Guangzhou Yishun Chemical Industry is suitable for nickel-plated alloy layer on the surface of iron parts, steel parts, zinc alloy, aluminum alloy and copper alloy after dipping zinc treatment. The coating is bright nickel-phosphorus alloy layer, excellent corrosion resistance and excellent binding force. Low price, low cost, non-toxic, environmental protection, do not need electroplating equipment.
Tin coatings are used in the food processing industry because of their non-toxicity, good ductility (toughness) and corrosion resistance. The excellent ductility of the tin coating can make the tin plating plate can be processed into various shapes without damaging the tin coating. The tin coating used to protect the steel plate must be pore-free, otherwise, the base steel plate will be seriously corroded in the humid air; Non-toxic, used in large quantities in contact with food and beverage. The biggest use is to make tin cans, other such as kitchen utensils, food cutlery, oven, etc. Easy to weld, good electrical conductivity; Improve the weldability of copper wire and the barrier between copper wire and insulating skin; The electroless tin plating liquid of Guangzhou Yishun Chemical industry can be used for electroless tin plating on the surface of copper alloys such as copper, brass and beryllium copper. The tin coating is bright silver white, which can increase the weldability and decoration of copper, does not affect the conductivity, anti-oxidation, and increase the appearance of copper workpieces. The products are non-toxic without heavy metals, and the salt spray test is more than 45 hours without rust. No plating equipment needed, just soak.
Can make a variety of deep stretching and bending manufacturing force parts, such as pins, rivets, washers, nuts, conduit, barometer spring, screen, radiator parts, etc.