That's right, stainless steel, not to say that you can't have carbon at all, it's to reduce carbon to a minimum of 0.3%, which is almost like pure iron, and then add chromium in a high-temperature environment, so that stainless steel can be refined.

From the very beginning, Zhao Xin had no intention of large-scale production, because the temperature of smelting stainless steel exceeded 1700 degrees, far above iron and steel.

Now that the problem has been discovered, of course, it is necessary to solve the problem, although the conditions for large-scale steelmaking are not very available, but in the laboratory, the dry pot is used to heat, and the temperature rises to about 1700 degrees Celsius with higher heat, and the carbon is replaced by the method of oxygen blowing, which is a very common method.

Oxygen, if it is replaced by this era, how to make pure oxygen is a big problem, Zhao Xin can even get out oxygen, as well as oxygen cylinders, which is very terrible.

Use a crucible the size of an ordinary pot, then seal a large amount of fuel, seal and concentrate the heat as much as possible, and after everything is done, start heating it in a professional laboratory.

Because, the thermometer provided by Niu Dali before, his limit was only 1400 degrees, above it, it was easy to damage, and it would not change color, and it lost the role of guidance, so he simply did not use it, so Niu Dali started the smelting process according to his own experience.

A piece of iron, which has been processed to a considerable extent, begins the process of melting.

When the temperature rises to 1200 degrees, the rock thermometer begins to gradually change color, from 1200 degrees to 1400 degrees, and then changes several times in succession, and finally, it loses its effect.

This is a key point, a point where the temperature has risen to 1400 degrees, and then Niu Dali can only calcine for more than half an hour according to experience, when the heat has obviously risen several grades, the heat in the whole laboratory is extraordinary, not only the iron has turned into a red liquid, and there are even signs of flow and boiling.

Of course, this is just a feeling, if the iron boils, it will be 2750 degrees, and the iron after vaporization will be very terrible, this is a heavy metal, containing this super heat, just like the high temperature of steam, once it rushes up, it will be dead.

Fortunately, the temperature did not rise so much, and after almost 1600 degrees, Niu vigorously began to blow oxygen into the dry pot through the tools.

The crucible, which itself was already tumbling, was blown by oxygen and quickly turbulent, and these oxygens also passed a certain amount of heating, and the temperature was higher, but to a certain extent, the temperature of the molten iron began to decrease.

However, in the high-temperature environment, the carbon in the hot iron liquid becomes a high-temperature ionic state, and it begins to combine with oxygen, and the carbon dioxide that becomes carbon dioxide begins to emit out, and puffs of black smoke emitted.

Itself, I don't think about Zhao Xin's actions, Niu Dali doesn't think that there are many things that can be cleaned up from the middle, but now, the real evidence is in front of me, it really can, pure oxygen and high temperature, the combination of the two, the carbon in the iron is cleaned out by a trace, and the purity of the iron has increased significantly.

Even with the help of the card system, it is impossible to make pure iron, high-purity metal materials have a unique role in many fields, and some special materials, for example, high-purity target tables in the laser field, require a purity of six or seven decimal places.

Each digit after the decimal point brings a huge cost, requiring layer by layer replacement, for some raw materials, to raise to this extent, the cost is huge.

A common joke in later generations is that CPUs are made of silicon, and the source of silicon is the sand on the beach.

However, from sand to silicon, and even the core silicon wafer in the computer, the scientific and technological content contained in it is not ordinarily large, the purer the silicon crystal, the faster the speed of the computer, and the higher the yield rate.

For a production line, hundreds of millions, or even billions, are often invested, which is still dollars, so from sand to CPU, it is like saying that the master's paintings, that is, are composed of pen, ink, paper, and inkstone, but without the master's creation, the difference between the things that anyone scribbles is very different.

Fortunately, the requirements for stainless steel are only high here, and the purity of pure iron has not reached the level of six or seven decimal places.

As long as the carbon content is less than 0.3%, it is fine, which can be seen when the temperature is maintained at about 1700 degrees Celsius and the oxygen is continuously blown.

In fact, Niu Dali also felt it, although he was not sure whether it met Zhao Xin's requirements, but the temperature remained at about 1700 degrees, he could calculate it, and it was basically right.

"Let's start adding chromium!" Zhao Xin ordered beside him.

The crucible test, because the temperature is too high, 1700 degrees, this temperature, even a little splash, has a huge killing effect.

Therefore, they are all under thick protective clothing, hiding far away, these rely on some relatively factory poles, far from manipulation.

With the help of oxygen, it is enough to remove most of it, which should already be below 0.3%, and in this form, with the addition of chromium, there is a high probability of success.

Zhao Xin didn't think that it would be impossible to manufacture a high-standard stainless steel with a high grade like that of later generations, such as a hardness of about 6.2, corrosion resistance, acid and alkali resistance, etc., he just needs to be about the same.

In fact, stainless steel, as a special steel, the first kind, his manufacturing difficulty is not high, Niu Dali if in strict accordance with Zhao Xin's requirements to do, will not continue to fail, now, under the guidance of Zhao Xin, everything is in order.

With the help of tungsten rod stirring, the chromium is quickly melted, and then the temperature begins to gradually decrease, from 1700 degrees to about 1400 degrees.

This is the limit of what a rock thermometer can measure, and a rock thermometer, added to it, and seeing that his color lasted to a certain extent, Niu Dali began to control the fire.

"Will it work this time?" Niu Dali asked, the continuous failures made his confidence not very strong, before, there were also a few times, there was a silver surface, it looked like yes, but after it cooled, it was black, and the overall form was not good at all, not even iron, let alone stainless steel.

Zhao Xin also has no bottom in his heart, the experiment, it is in the midst of continuous failure, gradually appearing, a failure can accumulate experience, and there is a card system, at the very least, you will know, what is made.

At that time, Niu Dali failed every time, and the finished products that were finally made were also scanned by Zhao Xin one by one.

In the later industrial era, many epoch-making inventions were scrap products from the original research, including stainless steel.

At that time, the British were looking for a wear-resistant super-hard steel to be used in the manufacture of gun barrels.

Stainless steel was manufactured in this context, but after it was manufactured, it was found that its hardness did not meet the requirements, so it was thrown aside.

Later, the war ended, and the needs of the war were not so important, but were used for civilian purposes, which made stainless steel shine.

This metal, which is difficult to corrode and can be used in a variety of daily necessities, has given rise to a wide range of applications.

From the temperature of about 1400 degrees, it takes time to reduce to normal temperature, Zhao Xin time is very precious, so he did not wait here, but Niu Dali, he not only waited here, but at the same time, opened several other experiments, that is, add different proportions, make different times.

According to the original plan, 10 formulas will be made this time, and under the premise that Niu Dali is alone, the time of one day is slightly not enough.

The next day, before Zhao Xin went to the laboratory, Niu Dali came running, and a hard, bright silver metal succeeded, and it was 8 times out of 10.

Zhao Xin sighed at Niu Dali's efforts, and also wanted to see that the final result of this eight times, there is a card system, which can save a lot of time, for example, as long as the card system is incorporated into the cards, you can know the full role of these things.

However, what surprised Zhao Xin was that among them, there was actually a stainless steel with a number of 6.1.

If you take a closer look, it is not only corrosion-resistant, acid-alkali resistant is very high, and even the hardness has reached 6.1.

Among the divine weapons, the strongest divine weapon is only 5.9 hardness, just like that, it can already be regarded as a terrible divine weapon, 6.1, 0.2 higher than before, that is, no matter how sharp it is, it is difficult to affect this.

This is very rare, Zhao Xin is just ready to make a simple, such as about 5.5, ordinary hardness stainless steel, compared with the previous sword, it is almost like a state of fine iron.

Now it is not only made, but it is more powerful than the magic weapon, that is to say, in the future test, there is a condition, that is, you can use a sharp sword to cut, and what has no trace is real money, at this point, it is incomparable to many ordinary iron.

This is an excellent selling point, Zhao Xin couldn't help but smile when he thought of this.

"Master Hou, did you succeed?" Niu Dali saw Zhao Xin's smiling face, and knew in his heart that it should have been successful, but he still had to ask.

Zhao Xin looked at Niu Dali's appearance, his heart moved, the performance of stainless steel, he knew, it can also be said to be immortal, but if people want to believe it, it must be said one by one, as long as Niu Dali is tested, put iron, fine iron, and this, into different environments, test, and finally form the result, it is worth convincing.

Moreover, the process of testing is also a process of experimental thinking, any after the experimental production of a product, gradually adjusted, and finally tested the performance of the product.

As for Zhao Xin, there are more important things to do, the raw materials are already there, which is equivalent to saying that the most difficult first level has passed, a little better than he expected, he needs to find a suitable way, carved and shaped, although it is said that there are not many things that are harder than 6.2, but it is not nothing, find a suitable pattern, let some handicraft masters, carve them into shape, that is the real currency.