In 962 A.D., January 1, this day is New Year's Day.

Although there is a New Year's Day in ancient times, but the date is not fixed, the Yin Dynasty is the first day of December as the day of New Year's Day, the Zhou Dynasty is on the first day of November, Qin Shi Huang period, and the first day of October is the New Year's Day, the New Year's Day of each dynasty is not the same time, the only thing that is the same is the first day of each month as the day of New Year's Day.

In order to facilitate management, Mei Xiaohan moved the time system of modern society to ancient times. The day was divided into 24 hours and the villagers were taught to look at the clock.

These children were the first to become familiar with the modern time system, and they were always curious about the magic of clocks.

When they saw the clock pointing to 21 o'clock, these children knew they were going to sleep.

By 5:30 a.m., the alarm clock will go off and these kids will know to get up. If you are familiar with the time, it will be much easier to push the next work.

No more listening to the rooster croaking, no more watching the sunrise and sunset, just looking at the clock to determine the time.

You can get money for studying, you can get money for participating in group activities, you can get more for more work, and there are additional subsidies for women and children, as well as for the elderly. In less than half a year, Wencheng Village has become a well-known village.

Everyone knows that there is a very wealthy village, and this village is Wencheng Village. The reform pilot has been very successful, and compared to other places, Wencheng Village has already thrown them a few streets.

A school has been established, which currently only admits students between the ages of 7 and 15 and is divided into three classes: beginner, intermediate and advanced.

Beginner class: hard pen writing, pinyin, picture speaking, Tang poetry, arithmetic.

Intermediate Class: Hard Pen Writing, Writing, Arithmetic, Basic Geometry, History.

Advanced Classes: Brush Calligraphy, Calligraphy Copying, Chinese Painting, Basic Physics and Chemistry, Industrial Basics, Basic Agriculture, etc.

Each child can choose according to his or her own situation, and there is no requirement to study every subject. When the concept of modernization is gradually instilled, the children have a new understanding of the world.

On the issue of education, Mei Xiaohan gradually let go, ready to let Zhang Yun and Zhang Liang do it. Mei Xiaohan's next job is to build a small ironworks.

Although she could choose to bring some farm tools from the modern society, Mei Xiaohan decided to build her own rigidity and iron.

Ancient ironmaking began in the Spring and Autumn Period. At that time, the ironmaking method was "block ironmaking", which reduced the iron ore to a solid state at a lower smelting temperature to obtain sponge iron, and then forged into iron blocks.

The wrought iron obtained in the early days is usually called lump iron, which is obtained by direct reduction of iron ore with charcoal at about 800 to 1,000 degrees Celsius. However, block iron has several disadvantages:

First, it can not flow out of the furnace, when the iron is taken out, the furnace will be damaged to varying degrees, and it cannot be continuously produced, the productivity is relatively low, and the output is relatively small.

Second, forming is labor-intensive and time-consuming.

Third, it contains more non-metallic inclusions, which can only be eliminated by repeated forging.

Fourth, the carbon content tends to be relatively low, so it is very soft.

The smelting temperature of pig iron is 1150 to 1300 degrees Celsius, the baked products are liquid, can be produced continuously, can be cast and molded, there are fewer non-metallic inclusions, the texture is relatively hard, and the smelting and forming rate is relatively high, so that the output and quality are greatly improved.

The ancient iron-making method was completely different from the rest of the world, and a large number of pig iron products were used, and the iron-making methods were:

At a furnace temperature of 1100-1200 degrees, the iron ore is melted and becomes cast iron after flowing out.

Cast iron is hard, but very brittle, and it is very difficult to use in practice, whether it is a weapon or an iron tool, it is not easy to use. But the ancients had no choice but to use this product.

At that time, there was only one way to get a piece of steel--- and that was forging!

Heat the pig iron to close to melting, and then repeatedly forge to remove impurities such as carbon, sulfur and phosphorus, the time is long enough, you will get a piece of steel, and then repeated forging method, you will get a piece of low carbon steel, this kind of steel with few impurities, called 100 steel.

Hundred steels are considered to be the best in iron, and if they are forged again, they will get wrought iron, which the ancients called soft iron. Later, the principle of steel filling and Suzhou steel was to mix raw and wrought iron with heating and forging.

The method of forging from pig iron to steel was time-consuming and laborious, and the output was extremely low, so Cao Cao spent three years in order to make five hundred steel knives.

Making iron is not easy in the first place, and making steel is even more difficult. The principle of steelmaking is to use oxygen or iron oxides to remove excess carbon and other impurities contained in pig iron into gas or slag under high temperature conditions.

According to the book, steelmaking methods can generally be divided into three methods: converter steelmaking, open-hearth steelmaking and electric furnace steelmaking. ：

1. Converter steelmaking method: The oxidant used in this steelmaking method is oxygen. Air is blown into molten pig iron to oxidize impurities such as silicon and manganese. During the oxidation process, a large amount of heat is released (1% silicon can raise the temperature of pig iron by 200 degrees Celsius), which can bring a sufficiently high temperature in the furnace. Therefore, converter steelmaking does not require additional fuel.

Converter steelmaking is carried out in a converter. The shape of the converter is like a pear, the inner wall has refractory bricks, and there are many small holes (air outlets) on the side of the furnace, and compressed air blows into the furnace from these small holes, which is also called a side blowing converter. At the beginning, the converter is at a level, liquid pig iron at 1300 degrees Celsius is injected inward, a certain amount of quicklime is added, and then air is blown in and the converter is turned to make it stand upright. At this time, the violent reaction on the surface of the liquid pig iron causes the oxidation of iron, silicon and manganese (FeO, SiO2, MnO,) to form slag, and the convection of the molten steel and slag is used to make the reaction spread throughout the furnace. After a few minutes, when only a small amount of silicon and manganese remains in the molten steel, the carbon begins to oxidize, producing carbon monoxide (exothermic) that causes the molten steel to boil violently. A huge flame appeared at the furnace mouth due to the combustion of spilled carbon monoxide. Finally, phosphorus also undergoes oxidation and further forms ferrous phosphate. Ferrous phosphate reacts with quicklime to form stable calcium phosphate and calcium sulfide, which together become slag.

When the phosphorus is gradually reduced by sulfur, the flame recedes, and the brown steam of ferric oxide appears at the mouth of the furnace, it indicates that the steel has been smelted. At this time, the blast should be stopped immediately, and the converter should be turned to a horizontal position, the molten steel should be poured into the molten steel ladle, and then the deoxidizer should be added for deoxidation. The whole process only takes about 15 minutes. If the air is blown in from the furnace, it is a low-blow converter.

With the development of oxygen production technology, oxygen top blowing converters (there are also side blowing converters) are now commonly used. This converter blows high-pressure industrial pure oxygen, which reacts more violently, which can further improve production efficiency and steel quality.

2. Open-hearth steelmaking method (open-hearth steelmaking method is also called Martin method, which has now been eliminated): the oxidant used in open-hearth steelmaking is introduced into the air and oxides in the charge, (scrap iron, scrap steel, iron ore). The heat required for the reaction is provided by burning gaseous fuels (blast furnace gas, generator gas) or liquid fuels (heavy oil).

The hearth of the open-hearth furnace is a groove made of refractory bricks, which is covered by a roof made of refractory bricks. There is a charging opening on the front wall of the open-hearth furnace from which the loader fills the charge. Close the door caused by the refractory bricks when smelting. At each end of the furnace are the furnace heads, each with two holes, for the introduction of fuel and hot air, or the use of gas from the furnace.

The raw materials used in open-hearth steelmaking are scrap steel, scrap iron, iron ore and solvents (limestone and quicklime). At the beginning of smelting, the fuel burns on the surface of the fuel in the face of the introduced hot air, at a temperature of up to 1800 degrees Celsius. The heat is transferred directly from the flame to the charge, causing the charge to melt rapidly (the melting point of iron is 1535 degrees Celsius, and the melting point of steel is slightly lower). At the same time, a part of the molten pig iron is formed into ferrous oxide, and the impurities in the pig iron are oxidized by ferrous oxide and sound into slag. As an excess of limestone is placed in the furnace, impurities such as phosphorus and sulfur form calcium phosphate and calcium sulfide as slag. Secondly, the carbon is oxidized, and carbon monoxide emerges from the molten metal as if the metal is boiling.

When the reaction is almost complete, add oxygen absorber and remove the slag regularly. At the end of the smelting, the composition of the steel is checked according to the pre-furnace analysis (which can be completed in a few minutes using the rapid analysis method). Technetium-smelting steel flows from the tap port into the ladle, from which it is injected into the mold to cast into products or ingots.

In order to increase the furnace temperature, the gaseous fuel is preheated in a regenerator.

In the open-hearth furnace, not only liquid pig iron can be added, but also solid pig iron, scrap iron and iron ore after tapping. In addition, if 30% oxygen-rich air is used in the open-hearth furnace and oxygen is blown into the molten metal at the same time, the productivity can be increased by 80%, the smelting time can be shortened by 2~4 hours, and the fuel can be saved, and the oxygen-rich air does not need to be preheated.

3. Electric furnace steelmaking method: steel can also be smelted in an electric furnace with electric energy as the heat source. High-quality alloy steels can be made using electric furnaces. There are many types of electric furnaces, and the most widely used is electric arc furnaces.

Steelmaking and ironmaking are two stages in steel production, generally iron is made first, then further steelmaking, and finally various types of steel are obtained.

If the process of producing steel is compared to making fried rice, then ironmaking can be regarded as the process of making rice, and second-steelmaking is the process of taking the finished rice and stir-frying.

At present, Mei Xiaohan's job is to make rice well, and first exercise high-quality iron.