Yan Zheng once read the investigation of Xunwu, and from this fact-seeking article, he can get a lot of information.

It's just that after all, this is an article hundreds of years later, so it can only be used for reference.

He asked Lehi Dog to inquire about the news, but he only got some superficial information.

It can be said that the investigation that Lehi Dog asked to carry out this time can almost be declared a failure.

But from these few words, Yan Zheng still filtered out some more useful information.

After thinking about it for a while, he felt that it would be better to specialize in some luxury goods in the future.

In addition, the linen industry can also be established, and a moderate semi-industrialization can be carried out to promote the development of the machine manufacturing industry.

The main industry was iron products, including but not limited to iron pots and iron farming implements, plus a possible future arms trade.

After the establishment of this industry, it can stimulate the development of the iron and steel industry, promote the development of machinery manufacturing, and promote the development of military equipment.

Whether from the perspective of civilian or military, or from the perspective of the market, steel products will become an unimpeded commodity in the future, no matter where they are, as long as they are shipped through, there will be buyers.

In view of the extremely differentiated structure of the Ming Dynasty, luxury goods can also shine.

Just like the fur, the rich people of the Ming Dynasty have very strong spending power.

After thinking for a long time, Yan Zheng silently spread out a piece of paper and wrote a line on it: The First Five-Year Plan.

As an important document that determines the development of the next five years, Yan Zheng intends to spend a few months sorting it out, which is also to clarify his thoughts and establish goals for future development.

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The next day, the Meaux Iron Works.

This ironworks was renamed the First Iron and Steel Plant by Yan Zheng.

After the import of pig iron and graphite, Yan Zheng expanded his production capacity again.

He deliberately handed over the matter of making crucibles to the pottery factory, and asked them to make each crucible strictly according to the recipe.

The finished product he got also made him very satisfied, and it has surpassed the one he made himself.

It seems that these clansmen have been making pottery for a long time, and they are already familiar with similar work.

With the further increase in the size of the crucible, the conditions for casting large parts have also been fully met.

It's just that the casting method is still a backward mud mold method, which is very time-consuming and troublesome, and the mud mold will generate moisture in the casting process, which will make the cast iron products have bubbles and affect their performance.

For this reason, Yan Zheng decided to immediately start the iron mold method, which is a simple but practical mold method. It is equivalent to replacing the container with iron, which dissipates heat faster during the manufacturing process and can be reused.

"Students, last time it was crucible steelmaking, this time I came to you to let you practice on the spot, from molten steel to what we want, we still need to go through those steps."

Yan Zheng once again found the group of students who had participated in the crucible steelmaking this time, and asked all the male students to come over to visit.

These students are also very curious and highly motivated. The reason is that the best treatment in the tribe is the blacksmith, followed by the potter and carpenter.

Yan Zheng stood next to the ironwood needle and asked the ironwood needle to demonstrate as he spoke.

"Everyone should have seen the hydraulic hammer, and that hydraulic hammer is to get the iron part we want by hammering. It's just that before that, there is another process, which is to use a mold to get a rough iron part first. ”

Ironwood Needle immediately took out a sand groove, showed it to these people, and then took out another clay mold.

Yan Zheng continued: "As you can see, the mud mold and the sand groove have some shapes, and these shapes are the iron parts we want, such as the sand groove, which is obviously a knife, as long as the molten steel flows in, after cooling, you can get a knife with a rough shape, and then you can get a finished knife by forging!"

As he spoke, the ironwood needle asked his subordinates to take out a cooled semi-finished knife and put it on the top of the sand mold, which fit perfectly.

"And the clay mold, the lost wax method is used! This clay mold is made by a craftsman who makes pottery, the principle is very simple, that is, the beeswax we collect will melt, we first make the shape we want, and then use the mud to paste well, and finally heat the wax will flow out! ”

"It's also very practical, because the wax can be reused, but it takes a long time! It takes about a month for a mold to dry! You can't use it if it doesn't dry out, because it will produce bubbles! Steel with bubbles is easy to break! ”

The ironwood needle asked people to take out a piece of iron, smashed it a few times, and then showed it to the students.

After reading it, the students all understood that those tiny bubbles in the iron would destroy a piece of iron.

Yan Zheng waited for them to look at each other, then said with a smile: "Now, we need to make a large number of steel products quickly, but the clay mold can only be made one at a time, and after it is made, the clay mold will be broken and taken out!" So if we want to achieve the goal, we must pass the mold level! ”

"What do you think you should use to make molds?" Yan Zheng asked.

These people naturally can't answer this kind of profound question, but they also start to think seriously one by one.

After a while, someone weakly asked if it was possible to make molds from pottery.

Yan Zheng shook his head and smiled bitterly, then he said, "Why can't we make molds from iron?" Cast iron with iron mold, the iron is solid and can be reused! ”

After listening to this, the students pondered for a while with their scarce imagination.

The smart ones reacted immediately, and they didn't know if they really understood or didn't know how to pretend to understand, anyway, these people all burst out with a sudden cry of enlightenment.

Yan Zheng smiled and took out a model of a gear carved by the carpenter, because it was used for demonstration, the size of this gear was not large.

Under everyone's curiosity, Yan Zheng first covered the sand on top of this wooden mold, the thickness of the sand layer was not thick, and the two-layer covering method was used.

After drying and shaping, fill the gap made by the wooden mold to ensure that it will not collapse when casting, and then it can be cast with molten steel.

Even molten steel needs too much, just make sure that this male mold is completely covered.

And the other side is also processed in the same way, and you can get an iron mold.

With the crucible steelmaking technology, it only took half a day to get the first iron mold.

Yan Zheng showed the finished product to everyone, and said while displaying: "The thickness of this one is a little thicker, which makes it a little bulky, but it is much better than the clay mold!"

As he spoke, he showed the use of the iron mold.

Brush two layers of slurry on the iron mold, the first layer of slurry is made of fine rice husk ash and fine sand mud, and the second layer of slurry is made of kiln coal after grinding water, which is why the Song family wants to get some coal, if you don't use coal, you can also use clay, but it will cause an unsmooth situation.

After brushing, it is directly dried, which is also unimaginable in the clay mold.

As long as you see the wide dog eyes of the ironwood needle, you can see the admiration of these blacksmiths at the moment.

They almost knelt down and looked up at Yan Zheng, such a whimsical idea was beyond their imagination.

After drying, it can be cast, and after the two iron molds are combined, they are tightened with iron hoops.

Once everything is ready, the molten steel can be poured directly into the process, as long as the process is kept slow and constant.

Because the thermal conductivity of iron is better than that of mud, the cooling rate of the iron mold is faster, and the cooling rate during casting will also affect its performance, and the faster the cooling rate, the harder the texture.

The next day, they had a near-perfect semi-finished gear, which declared the first iron mold test a great success.

It's just that the size is relatively small, and the test nature is too much.

However, this achievement still announced that Yan Zheng is really ahead of the world in the steel industry!

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