I am an industrial worker during the War of Resistance

Chapter 60 Medium Carbon Steel-Based Tungsten-Nickel-Molybdenum Alloy Gun Steel

Extracting molybdenum and tungsten from molybdenite is a very complex process.

First, the molybdenite ore must be crushed and ground into an extremely fine powder, reaching a mesh size of -200, in a ball mill.

Then, kerosene is used as a collector, pine oil (obtained by distillation of pine resin) is used as a frother, and molybdenum concentrate powder is obtained by flotation.

Molybdenum concentrate powder is roasted at 600 to 650 degrees Celsius in a rotary kiln, similar to the kiln used for cement production, to produce molybdenum trioxide.

During this process, a large amount of sulfides are emitted with the smoke, which is also the raw material for the production of sulfuric acid.

The roasted sand is then leached with ammonia water to produce an ammonium molybdate solution, which is then filtered again to remove impurities such as iron and silicon.

After evaporating and cooling the ammonium molybdate solution, ammonium molybdate crystals were left behind.

Finally, after the ammonium molybdate is thermally decomposed, it is heated to a high temperature in a hydrogen reduction furnace using a silicon carbide rod, which is then powered by resistance.

The furnace generates a high temperature of 900 to 1100 degrees Celsius, which reduces ammonium molybdate to molybdenum powder.

The ammonia water used in this process was obtained through nearly a year of experiments in a chemical laboratory.

It is formulated from synthetic ammonia synthesized in a laboratory setting.

Synthetic ammonia is the basic material for fertilizer urea, and it is also one of the intermediates in explosives.

Ammonia water can also be considered a type of fertilizer.

Chen Changzai had long wanted to develop chemical fertilizers for the sake of agricultural development.

However, producing synthetic ammonia is not an easy task.

Although its principle is very simple.

However, it involves combining nitrogen and hydrogen under high temperature and pressure.

Then the mixture is subjected to a high-pressure reaction at 10 to 30 MPa.

Finally, at a high temperature of 400 to 500 degrees Celsius, it is catalyzed by an iron-based catalyst and then liquefied at a low temperature.

This seemingly simple process took the chemistry lab almost a year to produce results.

However, these are only a small number of results produced in the laboratory.

Distance can be used industrially.

There's still a long way to go.

And so, only after Chen Chang had provided the preparation path beforehand was it possible to make it.

Although Chen Changzai knew these procedures, he never personally carried them out in his later years.

After all, when he worked at the explosives factory, the main raw material they used to manufacture explosives was toluene, not synthetic ammonia.

Even when there is a need to manufacture other synthetic explosives.

They also purchase synthetic ammonia from external suppliers instead of producing it themselves.

Later, he went to work in a military factory, where he had even less contact with things like synthetic ammonia.

Therefore, he could only teach the preparation process he knew to his students in the chemistry lab, letting them figure it out on their own.

The molybdenum ore residue after molybdenum extraction is not discarded.

There are many other metals in it.

For example, precious metals such as tungsten, gold, copper, lead, and rhenium, or rare metals.

Chen Chengshan and his team discovered that, superficially, molybdenite ore has a high content of both molybdenum and tungsten.

During molybdenum extraction.

The molybdenum content has reached 58%, which is the closest to the theoretical value.

Theoretically, the highest molybdenum content in molybdenite is 59.94%.

As a by-product, scheelite remains in the waste residue of molybdenite ore after molybdenum extraction.

Therefore, these waste residues still need to be further extracted using chemical methods.

The entire procedure is actually very similar to that for molybdenum extraction.

All of these methods involve modifying metallic tungsten through chemical means, extracting it, and then reducing it.

The only difference in the process is the chemical agents used.

But in the end, those waste residues still couldn't be discarded, because there was still rhenium metal there that couldn't be extracted using current methods.

Extracting molybdenum is like picking up a large piece of gold on the beach.

So, extracting rhenium involves sifting gold powder on a beach, and even then, only a very small amount of gold powder is extracted from a large area of ​​beach.

With the current equipment and capabilities in chemical laboratories, this is not yet possible. Therefore, the final waste residue can only be temporarily piled up in a ravine, to be dealt with later when the technology is more advanced.

What Chen Changzai needs most right now is tungsten and molybdenum, which, combined with the nickel he has on hand.

This allows the production of medium-carbon steel-based tungsten-nickel-molybdenum alloy steel.

Because it uses medium carbon steel as the base material, the demand for tungsten, molybdenum, and nickel is still within Chen Changzai's acceptable range.

According to the proportions he calculated.

For a 12.7mm heavy machine gun barrel that can be used for both high-altitude and low-altitude operations, only one to two kilograms of each of these added metals are needed for every hundred kilograms of alloy steel.

If it is a small-caliber artillery piece.

That would be slightly more, but not by much.

With this amount of usage, Chen Changzai's inventory, which still contained at least a thousand kilograms of nickel, should be enough to sustain him for some time.

Electric arc melting furnace workshop.

A small electric arc furnace with a capacity of 100 kilograms has been proportionally filled with medium and high carbon steel substrate and alloy materials such as tungsten, nickel, and molybdenum.

Wait until all the materials have been added.

A lid with three holes was placed on top.

At this moment, Chen Chengshan came to Chen Changzai and said to him, "Teacher, the electric furnace is ready and all inspections have been passed."

"We can begin smelting."

"Let's begin preparing for the electric melting process," Chen Changzai said.

After standing at attention and saluting, Chen Chengshan replied, "Yes, teacher, the electric arc furnace is starting to melt."

An electric arc furnace is essentially a large pot with a metal shell on the outside and refractory material inside.

It has a lid.

The three holes on the cover are the entry holes for the graphite electrode to enter the molten pool.

After the power is turned on.

The three-phase electricity generated by that 100-kilowatt generator will produce an electric arc inside the furnace.

The high temperature of an electric arc can quickly melt metal.

The principle is the same as that of electric welding.

Electric welding is a connection, while an electric arc furnace completely melts the metal.

After the various metals inside are completely fused together, a chemical reaction occurs.

Transform medium carbon steel into an extremely tough, wear-resistant, high-temperature resistant, and red-temperature resistant alloy steel.

The reason Chen Changzai made the stove so small was...

That's because a 100-kilowatt generator can only power a furnace weighing a maximum of 150 kilograms.

In order to reduce the load on the generator, Chen Changzai came up with this small 100-kilogram stove.

If someone asks, "With electric furnaces, why not use electroslag remelting? Wouldn't the steel produced be better that way?"
In later generations, there will be no more than ten countries in the entire world that are capable of electroslag remelting.

Why can't the Japanese manufacture their own third-generation tank gun barrels?
That is, they did not master the electroslag remelting technology that enables the manufacture of 5.5-meter cannon barrels.

So, this smelting technology has a simple name and a simple working principle.

Achieving this is not an easy task.

At least under the current conditions, Chen Changzai cannot achieve this.

Although Chen Changzai also possessed electroslag remelting technology.

However, given the current conditions, at least small electric arc furnaces are now available.

So, the hurdle of making alloy steel, which had been a stumbling block for Chen Changzai for so long, was finally overcome by him.

When the three graphite electrodes were energized, the furnace began to crackle and spark.

Chen Changzai knew that the ordeal he had endured with his students for over a month had ultimately brought him the best reward.

The sky above him was safe for the time being.

　Thank you to all my friends who have supported me.

　　Ugh, writing these technical paragraphs is exhausting; I spend 90% of my time researching technical information. And the information online is always full of errors, all sorts of nonsensical and irrelevant data.

　　The AI's results are always wrong, which is frustrating.

　　Hey!
　　
　
(End of this chapter)