Chapter 342

High temperature furnace project must be carried out by Jiuyi heavy industry.

This project is related to many things, especially the emerging powder metallurgy industry. There must also be the most important large tungsten crucible for sapphire, which can only be used after burning at a high temperature of more than 2250 ° for at least 48 hours. There is a great demand for tungsten and molybdenum products in industries such as nuclear industry, electronic industry, raw materials and machining tools

In fact, the core of the high-temperature furnace project is the large tungsten dry pot project.

Tungsten is a kind of non-ferrous metal with high hardness and high density. China's reserves and output rank first in the world. In the early 20th century, the warlords in Guangxi flourished because of the export of tungsten ore. Even many years after the founding of the people's Republic of China, China has no ability to produce tungsten powder and can only export tungsten ore.

For a long time, this thing was used in military affairs, and civilian use was the main component of metal cutting tools. After entering the 21st century, with the accumulation of China's technical research, various tungsten products began to be mass produced and exported to many countries in the world. Among them, the large tungsten crucible used to refine sapphire and monocrystalline silicon is the most typical representative.

When the gun barrel is melted, a certain percentage of tungsten powder is added to the molten steel to improve the wear resistance of the gun barrel, so as to improve the service life of the gun.

The melting point of tungsten is more than 3300 degrees. It is basically more difficult to make a crucible that can withstand such a high temperature with the existing technology in the world. Therefore, all kinds of tungsten products can only be processed by powder metallurgy, that is, metal sintering.

In powder metallurgy, vacuum high-temperature furnace is generally used, and the maximum temperature can reach the furnace temperature of 2700 degrees. The large tungsten crucible with purity greater than 99.95% is used to load parts and products.

China is a large tungsten producing country. In the early 21st century, China has ranked first in the world, far higher than the second United States and the third Russia.

A vacuum sintering high-temperature furnace with an inner diameter of 800mm costs more than 2 million, while the large tungsten crucible inside alone is worth more than 1.2 million.

The difficulty of high temperature furnace assembly lies in the manufacture of Dawu crucible.

Yun Fei used to work in state-owned enterprises. Although he was only at the grass-roots level, he still had a considerable understanding of this industry because a large part of the products in their workshop were tungsten and molybdenum products.

Before he left the world, the production of large tungsten crucible accounted for a large proportion in their company. When his company was developing Dawu crucible project, he and several teachers were responsible for tackling key machining projects.

The production of Dawu crucible goes through many processes from tungsten ore to the final finished product. The means to obtain tungsten powder with very high purity are chemical reactions. Yun Fei didn't know the details. Although his company also did this at that time, he didn't know the previous process of the powder because of department relations and some confidential things.

The powder is put into a special mold and then tamped manually (the tungsten powder can not be loaded with machinery, the current technology and highly automated equipment. The performance of the produced tungsten crucible can not be compared with that of manual, and the service life is very short. You can't load too much powder each time, usually five to ten kilograms), Put it into an isostatic pressure of 170 MPa for more than half an hour, and then turn the shape with a vertical lathe. This is the powder turning process.

Powder car is very important, because the workpiece will fall apart when it is slightly subjected to external force.

After the powder car, the risk of demoulding is very high. A large dock crucible with a diameter of 330mm, the diameter of powder billet exceeds 370mm (the shrinkage of powder metallurgy products is very large), and the powder loading weight exceeds 400kg. When demoulding, The crucible powder billet is pulled axially by the radial force of the rubber sleeve and steel sleeve outside the powder billet, and the powder billet is slowly taken out by using the gravity of the mold core with a weight of more than 300 kg inside. If you don't pay attention to it a little, the powder will be broken.

After the powder car, it enters the high-temperature furnace and is sintered at a high temperature of 2250 degrees.

Finally, it is machined to obtain the large dock crucible.

Machining is also a difficult problem. Most of the components of general cutting tools are tungsten, that is to say, it is difficult to process tungsten with tungsten. Of course, some people say that there are tools harder than tungsten, such as diamond blades and cubic boron nitride.

For such an idea, the cloud can only smile.

Tungsten is a very wear-resistant and high temperature resistant material. Diamond and cubic boron nitride, which are almost cutting tools in the grain structure on the surface of parts, are artifact tools at the level of heaven reliant sword and dragon slaying knife. However, for ultra difficult materials such as tungsten products, it is estimated that they are equivalent to cutting bones with stone age bone knives or stone knives.

For the processing of large tungsten crucible, domestic cutting tools are quite good in rough turning. At that time, Yunfei and others tested various cutting tools, and finally selected ys8 domestic cutting tools, which not only had high cost and good processing efficiency, but also had a cutting depth of 1-1.5mm on one side, which required high technical level of workers.

For finish machining, you can only choose the ultra-fine powder alloy tools produced by devils or the United States. A small 5 mm x 5 mm, 100 mm long blade, tax excluded, 400 yuan! This is still a friendship price. People who have no way in Japan or the United States can't buy it at all.

There is no such artifact in the domestic market. If Yunfei's company had not had a joint venture factory of tungsten and molybdenum products with Japan, they would not be able to compete with other domestic companies in finishing.

For such a difficult project, the investment can not be borne by Jiuyi heavy industry in a short time.

However, this is related to the third generation of smart phones and some high-end digital products, and also has a great relationship with the upgrading of chips. In order to realize the manufacturing of sapphire and monocrystalline silicon products in China in this era, even if there are great difficulties, we have to do it.

Otherwise, once the chip company makes all countries in the world feel egg pain, the most important silicon raw material must be cut off by the United States under Jewish control.

It is absolutely unacceptable for Yunfei to stretch out his neck and let others pinch him!

However, no matter how you look at it, it can not be completed by a private company. Without the support of the state and the investment of a large number of national scientific research departments, he will never do such a big injustice.

There are many companies producing tungsten and molybdenum products in China. At least, group companies such as Xiamen tungsten industry and China Minmetals have research institutes and manufacturing companies specializing in this material.

Unfortunately, they can only study tungsten wires that are not high in technology and used to make lamp filaments, as well as the production of not advanced mechanical cutting tools, and even molybdenum wires for wire cutting in electrical machining.

Before the 21st century, CNC cutting tools for precision machining in China were 100% imported!

"Mr. Sun, I know what you mean. However, this project, a private enterprise of Jiuyi heavy industry, can't afford it at all! We have no special material researchers and no special material research laboratory. The poor laboratory in the smelting workshop alone can not support the research of nano-sized cubic boron nitride and its related supporting projects. "

In order to continue to let the two old guys work hard for 91 heavy industry, Yun Fei had to explain in detail.

"Xiao Yun, when we put forward this project, we didn't mean that Jiuyi heavy industry should bear the research funds of this project. As long as we start the project first and make some progress, we can apply to the state for project funds..." although this matter was shamed by Yun Fei, situ Heyun still didn't want to give up.

He also knows that it is not fair for Yunfei to let Jiuyi heavy industry, which is already short of funds, undertake the initial research funds of this project.

When there are certain achievements in the future, the state will certainly fully accept them and may lead the research work. At that time, unless Jiuyi heavy industry fully undertakes all the research funds, it is impossible to have the technology exclusively.

From the understanding of Yunfei in recent years, this young man seems to have an incredible and even fanatical dedication to exclusive ownership!

"Project initiation? Yunlao, you are absolutely reliable in this matter? How many material professionals can our company count? Can we rely on these personnel of our company to produce materials that the whole country has not produced? " For situ Heyun's ignorance, Yun Fei was really angry.

Now I'm not afraid to offend this old man.

Take my private money and work for the country. Am I so selfless?

No,

I am a citizen!

"I remember you did automatic control, didn't you? You are a leader in electronic circuits. Are you also in materials? It's not easy for Jiuyi heavy industry to make money. Now there are several projects in the laboratory waiting for funds to start building factories! " Yun Fei said more and more impolitely. At this moment, he still forgot that situ Heyun, an academician who enjoys the national special allowance, only volunteered to help 91 heavy industry develop CNC machine tool technology.

"You..." situ Heyun was so angry that he couldn't speak.

"Mr. situ, are you all right?" Seeing situ Heyun holding his chest and unable to speak, Mao Yadong, sitting near the door to record the contents of the meeting, hurried forward to help the old man caress his chest and kept winking at Yun Fei.

However, Yun Fei, who was about to go on, didn't see her hint. When Yun Fei saw that the old man was angry, he was stunned.

If the old man is angry for good or bad, not only the company is not easy to explain, but Yunfei is also difficult to explain.

"Lao Wu, what are you waiting for? Call the aerospace hospital and call an ambulance!" Yun Fei was stunned for only a second and went crazy.

The old man's heart disease will not be angry!

If so, I will die!

The most important thing is, who will lead their own CNC machine tool research team after the old guys have turned their backs?