Because the hardness of steel is directly proportional to its carbon content, in order to forge wrought iron into "steel", in addition to repeated hammering, its carbon content must also be increased again... The reason why the Ming Dynasty's steelmaking industry is ahead of the world is that the key difference lies in this step.

For example, in Japan, when folding and forging, paper and wood ash are wrapped around the wrought iron for forging. This carburizing method is extremely inefficient. Therefore, the Japanese regard their steel knives as their lives, because it is not easy to get one.

The Ming Dynasty had two mature technologies, the steel-stifling method and the steel-pouring method, and their efficiency was many times higher than that of Japan.

Sugang, a specialty of Wuhu, uses the latter.

Zhao Hao saw that the steelmaking master first asked his apprentice to put the unforged wrought iron sheets into the ironmaking furnace, and there was also a worker beside him pulling the bellows to heat them.

About two minutes later, the apprentice used a large fire tongs to clamp one end of the pig iron and placed it obliquely in the furnace mouth. At the same time, he ordered his apprentice to blow more air to keep the furnace temperature rising.

In less than a minute, the pig iron tilted in the furnace began to melt, and molten iron kept dripping. At this time, the steelmaker took the big tongs from the apprentice, clamped the end of the pig iron outside the furnace, and began to move it left and right to evenly pour the molten iron onto the wrought iron below.

Because the melting point of wrought iron is higher than that of pig iron, even though it was put in first, it was only burned red and showed no signs of melting.

At the same time, the steelmaker kept turning the wrought iron sheet with his other hand so that both sides could be evenly drenched with molten iron. After drenching it twice, the master clamped the wrought iron on the anvil next to the furnace and asked the apprentice to forge it with a hammer.

After hammering it thousands of times and removing impurities, the craftsmen's dream of "steel" can be obtained.

Steel is so difficult to produce that its price is naturally much higher than bronze, which of course severely limits its sales.

So the craftsmen came up with a compromise. For example, if they wanted to make a big sword, they would first make the blade with wrought iron, and then only pour iron and steel on the blade. This is the so-called "using good steel on the blade."

~~

After visiting the steel mill, Zhao Hao felt like his throat was about to smoke.

Wang Yu had asked someone to prepare honeysuckle and mint tea for clearing away heat and relieving summer heat. Although it tasted strange, it was really effective.

After drinking a few large cups of wine, Zhao Hao finally suppressed the burning sensation and was in the mood to talk.

He was very satisfied with Wangji Steel Works, at least this production process... from ore washing and selection, to traditional coking, to mixed calcination of coke ore and sand, to steel frying or frying wrought iron, to the final steel pouring method... the general direction was basically correct.

Although from Mr. Zhao's perspective, there are a lot of problems in every link of production, but it also shows that there is a huge room for improvement.

In this way, we only need to continuously improve the process and increase the furnace temperature to provide the group with enough steel... Of course, this is the steel defined by Mr. Zhao, not the one in the craftsmen's minds.

"As long as we can change the square trough into a reverberatory furnace, we can easily raise the furnace temperature by several hundred degrees, and the quality of wrought iron can be greatly improved, so we don't need to use bronze to cast cannons anymore," Mr. Zhao thought secretly.

Jiangnan Bank launched a set of "bronze notes" a year later, with face values ​​of "500 Wen", "100 Wen", "50 Wen" and "10 Wen". On the one hand, it was used as a subsidiary currency of silver notes to expand circulation; on the other hand, it was used to collect enough copper for the group to meet the material needs of casting cannons and various castings.

There is no other way. Mining copper directly in the Ming Dynasty is too taboo. Copper is a circulating currency and only the government can mine it.

Therefore, Mr. Zhao eagerly looked forward to the day when high-quality wrought iron could be produced in large quantities.

By then, not only will it be no problem to make guns, cannons and steam engines, but even the Zhengtai railway promised to the old people will no longer be just a pie in the sky.

After talking about process improvement for a long time, the topic turned to why most of the iron-making furnaces were not in operation.

Wang Yu, who was originally excited, could not help but become depressed. He sighed and said, "Alas, my business is going downhill. I feel ashamed of my father."

"Why?" Zhao Hao asked, pretending to be puzzled. In fact, before departure, Secretary Ma would pick out the important information about today's itinerary and report it to the young master, so that he would have a clear idea.

Besides, Wang Ji’s operational difficulties have long been no secret.

"Alas, it's fate." Wang Yu sighed again and said, "We are family, there is no need to hide anything. The reason why my Wang family was able to quickly gain a foothold in the industry and increase Sugang's sales by thirty times in ten years is because of strong financial support and the help of noble people."

As he said this, he glanced at Zhao Hao and said, "Your ancestor is one of them, but the most important one is our fellow villager Hu Butang from Jixi."

Zhao Liben was a former subordinate of Hu Zongxian, so he naturally didn't worry that Mr. Zhao would be unhappy when he said this.

"Um."

Zhao Hao nodded and listened to him continue: "Hu Butang was able to fight against the Japanese with great strength, relying on the support of the prime minister in the court and the generous donations from us Huizhou folks. He had a steady stream of military funds to recruit soldiers and train troops. At that time, the entire southeast military was in disrepair, and all military equipment was in disrepair and had to be rebuilt."

"Hu Butang returned the favor by giving a large number of orders to Wangji. In addition, the weapons we made were indeed very strong and could fight against the Japanese pirates' Bailian swords. This made us famous and our sales were greatly expanded." He sighed and said, "It's a pity that not long after my father passed away, Hu Butang also died unjustly in prison. In addition, after the victory of the anti-Japanese war, weapons and guns were put into storage and horses were released to the mountains. Even if there were orders, they were all given to nearby relatives. My business gradually became deserted."

"I'll open one less furnace today and send off a master tomorrow, and before I knew it, I've become this half-dead state." Wang Yu said depressedly.

"We're still fighting the Tartars in the north, and Marshal Yu in the south is also trying to suppress pirates. How come there are no orders?" Zhao Hao asked softly, taking a sip of tea.

"The business in the north is monopolized by the ironworks of Shanxi merchants. Although their ironware is not as good as ours, it is more expensive. But the governor of the three borders only uses Shanxi ironware, so we can't get it at all." Wang Yu smiled bitterly and said, "As for Guangdong, their ironmaking level is already high and the price is not expensive. Who would choose far away instead of near?"

"Uncle Wang, why should you worry?" Zhao Hao couldn't help but laugh and said, "How much do you produce in a year? I'll take care of it all."

"Oh my," Wang Yu was excited at first, then he waved his hands and said repeatedly: "That's also several million kilograms, too much."

"Not much. Jiangnan Group has many places that need iron." Zhao Hao waved his hand proudly and said, "Apart from steel, the most urgently needed thing right now is wrought iron. I'll take as much as you have."

"That's great!" Wang Yu immediately looked tired and began to express his gratitude.

Although wrought iron currently has too many impurities and is not very useful for making weapons, it is more than enough to make farm implements and tools. Jiangnan Group has tens of thousands of workers in more than a dozen subsidiaries and 60,000 farm workers, so the need for ironware is huge.

With the rapid development of Jiangnan Group, its scale is getting bigger and bigger. It will not be difficult for it to take over the output of the entire Wuhu, let alone Wangji.

ps. This is the first of three consecutive updates. Please give me your monthly votes!