The Use of Lead and Zinc

Lead and zinc are widely used in fields such as electrical industry, mechanical industry, military industry, metallurgical industry, chemical industry, light industry, and pharmaceutical industry. In addition, lead metal has many uses in sectors such as the nuclear industry and petroleum industry. More than 80% of the world's lead is used to produce lead-acid batteries.

Zinc is an important non-ferrous metal raw material, second only to copper and aluminum in the consumption of non-ferrous metals. Zinc metal has good rolling resistance, wear resistance, and corrosion resistance, and can be made into alloys with better physical and chemical properties with multiple metals. The main products produced by primary zinc enterprises include metallic zinc, zinc based alloys, and zinc oxide. These products have a wide range of uses, mainly in the following aspects:

1. Galvanizing. Used as an anti-corrosion coating (such as galvanized sheet), it is widely used in industries such as automobiles, construction, shipbuilding, and light industry, accounting for approximately 46% of zinc usage.

Zinc has excellent atmospheric corrosion resistance, so it is mainly used for surface coating of steel and steel structural components. After the surface of hot-dip galvanized alloy for electroplating is oxidized, a uniform and fine protective layer of basic zinc carbonate ZnCo3Zn (OH) 2 oxide film is formed, which also has the function of preventing mold growth. Due to the excellent atmospheric corrosion resistance of zinc alloy sheets, Western countries have also begun to attempt to use them directly as roof covering materials. Using them as roof sheets can have a lifespan of up to 120-140 years and can be recycled, while using galvanized iron sheets as roof materials generally has a lifespan of 5-10 years.

2. Manufacturing copper alloy materials (such as brass). Used in the automotive and mechanical industries, accounting for approximately 15% of zinc usage.

Zinc has suitable mechanical properties. Zinc itself has low strength and hardness. After adding alloy elements such as aluminum and copper, its strength and hardness are greatly improved, especially with the emergence of zinc copper titanium alloy. Its comprehensive mechanical properties have approached or reached the level of aluminum alloy, brass, and gray cast iron, and its creep resistance has also been greatly improved. Therefore, zinc copper titanium alloy has been widely used in hardware production.

3. Used for casting zinc alloys. Mainly used as die castings in industries such as automobiles and light industry, accounting for approximately 15% of zinc usage.

Many zinc alloys have excellent processing performance, with a pass processing rate of 60-80%. Excellent medium pressure performance, capable of deep drawing and self-lubricating, extending the life of the mold. It can be welded by brazing, resistance welding, or arc welding (in helium gas), and the surface can be electroplated or painted. The cutting performance is good, and it has excellent superplastic performance under certain conditions.

In addition, zinc has good electromagnetic field resistance. The conductivity of zinc is 29% of that of standard electrical copper, and zinc plate is a very effective shielding material in situations of radio frequency interference. Meanwhile, as zinc is non magnetic, it is suitable for making materials for instrument parts, instrument shells, and coins. In addition, zinc itself and its collision with other metals will not cause sparks, making it suitable for underground explosion-proof equipment.

4. Used for manufacturing zinc oxide. Widely used in industries such as rubber, coatings, enamel, pharmaceuticals, printing, fiber, etc., accounting for approximately 11% of zinc usage.

5. Used for manufacturing dry batteries, appearing in the form of zinc cakes and zinc plates, accounting for approximately 13% of zinc usage.

Zinc has suitable chemical properties. Zinc can interact with NH4CI, releasing H+positive ions. Zinc manganese dioxide batteries utilize the characteristics of zinc, using zinc alloy as the outer shell of the battery, which serves as a container for the battery electrolyte and participates in the battery reaction to form the anode of the battery. In addition, its performance has also been widely applied in the pharmaceutical industry.

The world's lead consumption is mainly concentrated in the fields of lead-acid batteries, chemicals, lead plates and pipes, solder, and lead bombs, with lead-acid batteries being the most important area of lead consumption. In 2009, the proportion of lead consumption in lead-acid batteries in the United States, Japan, and China reached 86%, 86%, and 81.4%, respectively. Based on environmental requirements, the consumption of lead in other fields is relatively low.