How was the earliest metal of mankind smelted?

Early use of natural metals (copper, gold, meteorites)

The earliest metallurgy

Early metallurgy in China

Bronze Age

Bronzes before Shang Dynasty in China

Shang and Zhou bronze castings

Use of other metals

Iron Age

The discovery and application of iron

China smelting iron

The Invention and Development of Cast Iron in China

China's pig iron steelmaking

China Iron and Steel Production Equipment, Fuel and Auxiliary Materials

The influence of China's ancient steel technology on other countries; European ironmaking technology in Roman Empire.

Other achievements of ancient metallurgy in China.

Casting technology

Metal surface decoration technology

Other metals and their alloys

Characteristics of Ancient Metallurgical Development in China

Development of modern metallurgical technology

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In the late Neolithic period, people began to use metals and experienced several copper-bronze (including copper arsenic, copper tin, copper lead and copper-zinc alloy, see copper alloy-iron (including massive ironmaking, pig iron, wrought iron or steel). Countries all over the world entered the bronze age and the iron age at different times, and the road of technological development also has its own characteristics. Metallurgical technology and the use of metals are closely related to human civilization. The Neolithic pottery-making technology (firing black pottery in high temperature reducing atmosphere) promoted the emergence and development of metallurgical technology. The development of metallurgical technology provides household appliances, production tools and weapons made of bronze, iron and other metals and various alloy materials, which improves social productivity and promotes social progress. The progress of metallurgical technology in China, India, North Africa and West Asia is closely related to the ancient civilizations there. /kloc-After 0/6th century, pig iron smelting technology spread to all parts of western Europe, which led to the development of metallurgical technology based on coal smelting iron. This development was later combined with the achievements of physics, chemistry and mechanics, which enhanced the understanding of metallurgy and metals, gradually formed metallurgy, and further promoted the development of modern metallurgical technology.

Bronze Age ── Bronze Stone Age

Humans began to use natural metals in the late Neolithic period. Since then, bronzes have been gradually smelted from ores. At this time, stone tools were mainly used, and a small number of bronzes were also used, which was called the Bronze Age or Bronze Age.

The early use of natural metals (copper, gold, meteorites) was in the Arikosh area in western Iran, and copper beads made of natural copper sheets were discovered in 7 and 8 thousand BC. A bronze needle dating back to 5000 BC was found in Tepe Sialk, south of Lake Namak in central Iran. Bronzes made of natural copper in the late 5000 BC were discovered in Yahya, south of Kerman.

Although natural gold is easy to find, it is generally small in size and quantity. The utilization of placer gold is waiting for the emergence of metallurgical methods, so it appears late. At present, the earliest gold products found in the world were in 5000 BC. The earliest metal used in South America was natural gold. In Peru, gold processing began in 1500 BC, while copper and copper-silver alloys were used after 1000 BC. 11~1The Jin people in the 4th century reflected Indian culture. Meteorites are not as easy to identify as natural copper and gold, and they are used late. At present, the earliest meteorites are iron beads and daggers (containing 7.5 ~ 10.9% nickel) dating back to 4000 BC, which were unearthed in Goelzer in the Nile Valley and Ur in the Euphrates River Valley.

The earliest meteorite cultural relic in China is the Gaocheng iron-bladed copper mussel in the middle of Shang Dynasty (about 65438 BC+the middle of 3rd century BC). (See color map) The earliest metallurgical natural metal resources are limited. In order to obtain more metals, we can only make metals by smelting ores. In the process of looking for stone tools, human beings learned about minerals and created metallurgical technology in pottery firing production.

Copper smelting from ore is an important milestone in the development of human culture. Copper oxide ore (such as malachite) is used for the first time. Oxidized ore is mixed with charcoal and reduced by heating to obtain metallic copper. The earliest known artificially smelted bronzes were unearthed in Yahya, Iran (about 3800 BC), containing a small amount of arsenic (0.3 ~ 3.7%), and some of them were cast, cold-worked and annealed. At the same time, Egypt and Mesopotamia also used bronzes containing nickel or arsenic. Basic copper arsenite is similar to malachite, and it is easier to smelt arsenic bronze with it or copper arsenite, while nickel is often produced with copper, and nickel and copper are easy to smelt. The use of arsenic copper and nickel copper lasted for a long time. Copper smelting technology in the Middle East spread to Europe and India in 3000 BC, maintaining the characteristics of containing nickel and using arsenic. In later bronzes, such as the Harappa culture in the Indus Valley, there were also tin bronzes containing arsenic or nickel from 2500 BC to 2000 BC. The earliest known bronze ware containing tin was produced in the first dynasty of Ur in Iraq today (2800 BC), containing 8 ~ 10% tin.

China's Early Metallurgical Bronze Knife of Majiayao Culture in Dongxiang, Gansu, China (containing 6 ~ 10% tin) is the earliest bronze found in China so far. At about the beginning of the third Millennium BC, it appeared at the same time as Ur bronzes. In addition, the bronze knives of Machang culture are equivalent to the tin bronze age of Harappa culture in the Indus Valley in the late third millennium BC, and the tin bronze age unearthed in Nor Nok Tha, northern Thailand in Southeast Asia. The appearance and development of tin bronze in China is similar to the history of the two river basins, but earlier than that in Southeast Asia. Moreover, there were no stages of As-Cu and Ni-Cu alloys in early China, which indicated that China bronze technology was developed independently.

Qingtong times

Bronze mainly refers to copper-tin alloy, and ancient bronze often contains lead or other metals. Adding tin to copper can improve performance. The melting point of bronze is lower than that of copper, and its casting performance is good, so it has gradually become the main variety of ancient bronzes. The earliest tin bronze appeared in the two river basins, about 3000 BC to 2500 BC. In the second Millennium BC, the smelting technology of copper and bronze reached its heyday. The bronze age in Egypt began around 2600 BC. In Europe, tin bronze appeared after the arsenic-copper era from BC 1800 to BC 1500.

Bronzes before Shang Dynasty in China Before Shang Dynasty and at the beginning of Shang Dynasty, there were some bronzes in the Yellow River valley, including red bronze, tin bronze and lead bronze. The extremely primitive brass cone of Longshan culture was unearthed in Jiaoxian County, Shandong Province. Bronzes unearthed in Dengfeng, Henan Province at the end of 3,000 BC (see color map). The third phase of Erlitou Culture in Yanshi, Henan Province (BC17th century) has been able to cast more complex bronzes such as cones, brooms, bells and bronze jue. Bronzes, bronze statues and stone models have also been unearthed in Xiajiadian lower culture. A large number of bronzes, bronzes and gold and silver ornaments have appeared in Qijia culture and Huoshaogou culture sites in Gansu Province. At this time, I have mastered the technology of casting hollow objects, such as the head of a bronze four-sheep-joint staff. The scepter head also adopts embedded casting technology, which embodies a high casting level. Bronze Casting in Shang and Zhou Dynasties The Shang and Zhou Dynasties were the heyday of Chinese bronzes, and reached the peak of the world at that time in technology. A large number of bronzes cast in Shang and Zhou Dynasties were unearthed, including production tools (axe, hoe, drill, knife, chip, saw, cone, etc. ) and farm tools (hoes, shovels, shovels, 6? 1), weapons (ge, spear, cymbal, arrow, etc. ) and a large number of ritual vessels and utensils. Nearly 30 tin bronzes from the early Shang Dynasty (BC 1 6th century) were unearthed in Erlitou, Yanshi, Henan (Figure1). Two pieces of Fang Ding unearthed in Zhengzhou, Henan Province in the middle of Shang Dynasty (Figure 2) weigh 64.2kg and 82.3kg respectively, and are about 1m high. The latter contains 17% lead and 3.5% tin. The Simu Wuding unearthed in Anyang, Henan Province (see color map) is the largest ancient bronze ware unearthed so far in the world. This reflects the outstanding technology and grand scale of bronze casting in the late Shang Dynasty in China. Copper ingots are often found in ancient casting sites, but there are few copper remains. It can be inferred that at this time, the copper material melted in the copper smelting plant (see Tonglushan mining and smelting site) was used, and the bronze ware was made in the foundry. Foundry technology Most of the bronzes in Shang and Zhou Dynasties in China were cast in clay molds, but in the later period, like other countries in the world, a small amount of copper molds were used. More than 440 exquisite bronzes have been unearthed from male and female tombs in Yin Ruins, some of which are basically the same in shape and size. It may be that several sets of models have been made with one set of molds. There are also castings with complex structures in these bronzes, such as steam column retort (bronze boiler) (Figures 3 and 4). During this period, many exquisite bronzes were cast by pottery and casting, such as Siyang statue unearthed in Hunan (see color map) and Lotus Crane Square Pot unearthed in Henan (Figure 5). At the turn of the Spring and Autumn Period and the Warring States Period (from 6th century BC to 5th century BC), the clay chime was not only a brilliant creation in acoustics and law, but also an outstanding achievement in bronze casting technology. More than 4,000 bronzes, weighing 10 ton, were unearthed from the tomb of Zeng Houyi in Sui County, Hubei Province (about 430 BC), including 64 bronze bells with two tones each. In addition, the king of Chu also presented an earthen clock weighing 135 kg (see color map), and two large jars weighing 320 kg were unearthed in the same tomb, as well as a set of extremely complicated statues and plates cast by lost wax method. An important development of copper smelting with ore and flux is the use of copper sulfide ore. In the Alps, copper sulfide ore has been used at the latest in 1200 BC, and 40 kg copper ingots have been produced.

In China, copper ore used in ancient times was mainly copper oxide. Timber structure support and drainage lifting equipment are used in Tonglushan mining and metallurgy site in Daye, Hubei Province. The ore is smelted by shaft furnace in the mining area, and there are about 400,000 tons of glassy slag with good fluidity and good copper slag separation nearby, with an average copper content of 0.7%. According to the composition of slag and hematite beside the furnace, flux is used to adjust the composition of slag during smelting to improve the fluidity of slag.

Smelting equipment In terms of smelting equipment, ceramic containers were first used, which were heated from the outside or directly buried in charcoal, heated and burned to obtain high temperature and reducing atmosphere. Later, it developed into a floor furnace with tuyere and a diameter of about 60 cm. In China, pottery statues were used in the early days, with grass mixed with soil coated on the outside to insulate the heat, and refractory mud coated on the inside, and copper ore and charcoal were directly put into the furnace. This device is different from the externally heated "crucible" melting, which can increase the temperature in the furnace. This internally heated ceramic furnace has developed into a vertical furnace made of clay or prefabricated ceramic rings, with holes in the lower part for direct slag tapping and copper tapping, such as the furnace in Chunqiu Metallurgical and Casting Plant in Houma, Shanxi.

On the basis of smelting and casting in Shang and Zhou Dynasties, Kao Gong Ji at the end of the Warring States Period (3rd century BC) recorded the alloy composition used in casting various bronzes, namely "Six Gases", which is the earliest known record about the law of alloy composition in the world. Lv Chunqiu Bielei (about 240 BC) recorded that "gold (that is, copper) is soft in tin, and the combination of the two softness makes it hard", which is the earliest narrative about alloy strengthening in the world. Xunzi (365,438 BC+03-238 BC) pointed out that when casting bronze, "the punishment is correct, the gold is beautiful, the industry is skillful, and the fire is extinct", that is, the casting model is accurate, the raw materials are pure, the technology is meticulous, and the temperature composition is suitable, which is also an early record of casting technology. In the second millennium BC, lead bronze, lead-tin bronze and tin bronze were widely used in China.

Before 3000 BC, the use of other metals such as lead, silver and gold was extremely rare. However, in the early bronze age of 3000 BC, they often appeared in cellars or graves of various cultures from Greece to China. Silver alloy daggers with copper content of 27.5% appeared in the two river basins. At that time, silver was extracted from lead by soot blowing.

The application of bronze is still in a prosperous period, and iron has entered the historical stage.