The role of heat treatment is gradually known in the course of the Stone Age to the bronze and Iron ages. Early in the Shang Dynasty, there has been a recrystallization of the gold ornaments.
In the first 222 years of 770~ BC, the Chinese have found in production practice that the properties of copper and iron will change due to the effects of temperature and pressure deformation. The soft treatment of white cast iron is an important process of making tools.
Sixth century BC, iron and steel weapons are gradually adopted, in order to improve the hardness of steel, quenching process has been rapidly developed.
The two swords and a spear unearthed in the Yan Xia of Yi County, Hebei Province of China, have martensite in their microstructure, indicating that they have been quenched. With the development of quenching technology, the influence of quenching agent on quenching quality is gradually discovered. The Three Kingdoms Shu people pu Yuan had in this Shaanxi Oblique valley for Zhuge Liang Dozen 3000 knives, it is said to send people to Chengdu to take water quenching. This shows that China in ancient times to notice the cooling capacity of different water quality, but also pay attention to the oil and urine cooling capacity. Unearthed in the Western Han Dynasty (A.D. 206~ A.D. 24) Zhongshan Jing Wang Tomb of the Sword, the heart of the 0.15~0.4% carbon content, while the surface carbon content of more than 0.6%, indicating that the carburizing process has been applied. However, as a personal "craft" of the secret, refused to be rumored, so the development is very slow.
In the 1863, British metallographic scientists and geologists showed six different metallographic microstructure of steel under microscope, which showed that the microstructure of steel was changed in the process of heating and cooling, and the phase in the steel was transformed into a hard phase when the heat was cold. The iron-homogeneous heterogeneity theory established by the Frenchman, as well as the earliest iron-carbon phase diagram developed by the British Austin, have laid a theoretical foundation for the modern heat treatment process. At the same time, the method of metal protection during heat treatment is studied to avoid the oxidation and decarbonization of metals during heating process.
1850-1880 years, for the application of various gases (such as hydrogen, gas, carbon monoxide, etc.) to protect the heating has a series of patents. 1889-1890 years, the British lake to obtain a variety of metal bright heat treatment patents.
Since 20th century, the development of metal physics and the transplanting of other new technologies have made the metal heat treatment process much more developed. A notable advance is 1901-1925 years, in the industrial production of the use of rotary furnace for gas carburizing; The 30 's dew point potential difference, the furnace atmosphere of the carbon potential to achieve controllable, and then the use of carbon dioxide infrared meter, oxygen probes, etc. to further control the atmosphere carbon potential in the furnace method; the 60 generation,
Heat treatment technology uses the role of plasma field, the development of ion nitriding, carburizing technology, laser, electron beam technology, the use of metal to obtain a new surface heat treatment and chemical heat treatment methods.
ADDRESS: Tong Yu Jie dao Goat Village, Taizhou, Zhejiang Province, China
Please fill in your mailbox information