China's three ancient casting technology is what

The working people through generations of long-term production practice, created a traditional casting process with our national characteristics.

In particular, the mud model, iron model and molten mold casting is the most important, called the ancient three casting technology.

There are many ancient documents on the Kunwu (a tribe in the Xia Dynasty, living in Puyang City, Henan Province, north of the territory of the present-day), pottery, copper casting records, and Yu cast the legend of the Nine Cauldrons.

From recent archaeological excavations, the Xia Dynasty has been able to melt and cast bronze.

The first casting was done using stone models.

Because stone is not easy to work with and is not resistant to high temperatures, it was soon changed to clay models based on the development of pottery making, and it remained the dominant casting method for more than 3,000 years, until sand casting was adopted with the rise of modern machine building.

Early Shang dynasty to Henan Yanshi Erlitou site as a symbol, has been cast in clay casting, copper chisel and other small production tools and copper bell, copper jug and other daily utensils.

A little later, with Zhengzhou Erligang as a symbol, bronze smelting and casting began to develop.

Zhengzhou Zhang Zhai unearthed two large square tripod, respectively, weighing *** -25 and eighty-two -25 kilograms, indicating that the middle of the Shang Dynasty bronze casting technology already has a considerable level, from the single-sided Fan, double-sided Fan casting, the development of a number of types, core composite casting Fan casting weighing more than a hundred pounds of large castings.

The casting material from the stone and mud, sand to metal, from a type by a number of type and improve the durability of the so-called higher "permanent" type (that is, the metal type), in the historical development of casting technology is of great significance.

In 1953, Hebei Xinglong iron model discovery, proved that China as early as in the Warring States period has been using white iron metal type cast pig iron castings.

This batch of iron models including hoes, sickles, axes, chisels, car tools and other categories *** eighty-seven pieces, most of the complete supporting.

Among them, the sickle and chisel is a Fan two pieces, hoe and axe also used a metal core.

They are very compact and quite distinctive.

The shape of the van coincides with the casting, so that the wall thickness is uniform, which is conducive to heat dissipation; the wall of the van comes with a handle, so that it can be gripped, and can increase the rigidity of the van.

It can be said to have created a Chinese style of metal type, and has been largely finalized at that time.

In recent years, in Nanyang, Henan, Zhengzhou, Zhenping and Hebei Mancheng, Shandong Laiwu and other places have been unearthed in the Han Dynasty iron Fan many pieces, more varieties than the period of the Warring States period significantly increased, the type is basically the same.

In the Han-Wei iron cellar in Mianchi, Henan, there are also casting iron plates and arrowheads, as well as a half-meter-long large iron plow.

In addition to iron metal forms, copper metal forms were already used to mint coins during the Warring States period and the Han dynasty (e.g., the five-baht copper forms that have been handed down and unearthed, etc.).

They played an important role in production, but in the literature, it is rare to see records.

In the Han Shu - Dong Zhongshu biography, it says: "As if the gold in the ■, but the smelter.

""■"" word note: "It is called the mold of the casting.

"This can be recognized as the earliest account of metal casting.

But later this "■" character and "熔" character more common, lost its original meaning.

Traditional investment casting is generally referred to as lost wax, wax out, or pinch wax, dial wax.

It is used to manufacture turbine blades, milling cutters and other precision castings of modern investment casting, whether in the wax used, mold making, modeling materials, process methods, etc., are very different.

However, their process principles are the same, and, the modern investment casting is developed from the traditional investment casting.

Gui Fu (1736-1805) of the Qing Dynasty said: "Han seal more dial wax".

Some of the Han seals with animal buttons, button system is small, complex shape, and there is no obvious burin, chisel traces, is likely to be lost wax casting.

Yunnan Shizhai Mountain unearthed in the Han Dynasty Dian cultural relics storage shell cover (see the book page 518 of the figure), is also a lost wax casting.

In 1978, Hubei Suixian unearthed Zenghouyi Zun disk and in 1979 Henan Zhechuan unearthed Chu copper ban, after research, are lost wax method of casting, indicating that China in the Spring and Autumn period has been invented this technology.