Five days later, the blacksmith battalion.

Liu Yu's eyes were bloodshot, his eyes were red, but there was no trace of tiredness on his face, and now his entire face was blackened by the fire, and only this pair of red eyes were left on his entire face, still staring at the cyan hearth, and the red knife-like steel block on the iron furnace.

Kong Jing on the side was already shirtless, personally pulling the bellows on the side, while the hairball was holding a few black briquettes in his hands, nervously looking at the fire in the hearth, his hands were trembling slightly.

With a "horn", a briquette in the hearth exploded, and a few sparks burst out and bounced onto Liu Yu's body, suddenly emitting a few wisps of light smoke, and the fire in the furnace also turned from red to green.

Liu Yu jumped up all of a sudden, and yelled: "It's now, throw the graphite ball!" ”

A few briquettes in the hairball's hand were quickly thrown into the hearth, and they were immediately engulfed by the raging flames, and the fire in the furnace suddenly became a pure green, and the heat wave that could almost melt people came to the face, and it could almost set people on fire!

Liu Yu flew up and kicked the iron door of the hearth shut, Kong Jing on the side, gritted his teeth and glared at the wind, the speed was at least twice as fast as just now, and with the sudden acceleration of his movements, the entire blacksmith shop was like a crater, and the sweat on his body just came out, and it was dried up.

Liu Yu didn't say a word, after kicking the door of the furnace, he picked up a big hammer, Maoqiu and Feng Qian picked up a pair of big pliers, and tightly clamped the red-hot steel block on the stove, but if you look carefully, you can find that this whole knife-shaped steel bar is actually divided into two parts, and the layer of the blade is about three or four inches thick, which is not the same as the material of the back of the entire knife body, and even the color that turns red after heating is also different.

Liu Yu picked up the sledgehammer and began to smash the two pieces of steel non-stop, and the hairball flipped the side of the blade and lifted it to the center of the iron slull, Liu Yu's arm muscles, with his knocking, bulged one by one, and after every few strokes, the hairball would continue to take the knife-shaped red steel back to the stove to heat, faintly, you can see some black things, penetrating from the edge to the blade and the back of the knife, as fine as particles, and Feng Qian will also hold a small bag of charcoal powder, and follow Liu Yu and Kong Jing's instructions from time to time, Sprinkle a little bit on the back of the knife.

In this way, after hammering more than seventy times, Kong Jing stopped the bellows in his hand and said in a deep voice: "It's almost." ”

Liu Yu nodded, put down the hammer in his hand, stepped forward to take the big tongs in the hand of the hairball, and soaked the whole piece of steel into the shape of a knife, and the large piece on the back of the knife into a bucket of grease on the side.

But the big piece of the blade is still left outside this bucket of grease, although a large piece on the back is slowly fading red, but the large piece left on the outside is still as if it is about to melt, Liu Yu's hand does not move at all, ensuring that the three inches of the blade are red, not into the grease, until a quarter of an hour later, he lifted this piece of knife steel, only to see that the back has turned blue and black, no longer hot, and the three inches of the blade are still red, steaming.

Liu Yu directly put the part of the blade into the iron furnace, Kong Jing puffed up the fire again, and after roasting for a few minutes, the whole blade was red and purple again, this time Liu Yu only smashed it a few times, and then soaked this blade into another bucket of urine that was filled with shame placed next to it.

With a "zing" sound, the entire blacksmith shop was filled with a smell of Chinese desire, making people feel as if they were in a pit, Liu Yu's brows furrowed, which reminded him of the experience of drilling the dung tunnel when he assassinated the Diao brothers last time, and the smell was so familiar. And this time, in order to quench, I also deliberately took the urine of five kinds of livestock, such as pigs, cattle, sheep, horses, and donkeys.

Liu Yu thought about it, and couldn't help but be distracted, until Kong Jing on the side said loudly: "It's okay!" Only then did he react and took the piece of steel out of the bucket. It is evident that the edge of the blade is a bronze color, faintly glowing with purple, while the back of the knife is a blue-black color, which is the color of the wrought iron that has penetrated into the charcoal powder.

Kong Jing rushed to the knife with an arrow step, carefully studied the color of the blade and the stripes on the knife, and kept nodding his head: "Okay, it's really good, I can't imagine that this Xianbei people's knife refining method is so magical, using 100 steel as the blade, wrought iron as the back of the knife, when mixing and refining, the charcoal powder in the 100 steel can penetrate into the back of the knife, making the wrought iron hard, and not losing toughness!" ”

Liu Yu laughed, holding the big iron tongs, holding this blade, and facing a fine iron armor placed on the side, he waved it hard, only to hear a "whoosh", this iron armor made of stainless steel armor leaves, in front of this knife, was like a tofu block, which was halved into two halves, from the chest down, and fell to the ground heavily.

Kong Jing's eyes widened: "It's so powerful, I can't imagine that with the drowning of these five animals, there is such a divine weapon, it is really like sharpening iron like clay." There was also a burst of cheers in the blacksmith shop, and many craftsmen who had been busy for several days and nights hugged each other excitedly, and tears flowed from their eyes.

Liu Yu's gaze fell on the back of the knife: "Under my knife just now, the back of the knife does not have that feeling of difficulty at all, and the texture has not changed, from this point of view, this knife is on the battlefield, and it can cut such an iron armor for at least twenty or thirty pays, which is enough to deal with the whole battle!" ”

Kong Jing let out a sigh: "Liu Yu, you are really a gift from God to the soldiers of Beifu, this knife is made by you, so you will name it." And this steelmaking method of mixing 100 steelmaking and wrought iron together, it is also up to you to name it! ”

Liu Yu smiled slightly: "The charcoal powder is infiltrated into wrought iron by 100 steel, which is similar to infusion, and this steelmaking method is called the steel-filling method." As for this knife? He groaned for a moment, "The edge of the hundred refining steel is placed on the wrought iron blade, which is like a boarding, this knife is called the hundred refining iron knife!" ”

Xie Xuan's voice came from outside the blacksmith shop with his applause, and his figure, accompanied by more than a dozen guards, slowly walked in.

After Liu Yu gave a military salute, he knelt on one knee, held the knife with both hands, dedicated it to Xie Xuan, and said in a deep voice: "Xuan Shuai, the humble duty is fortunate to live up to the mission, the kind of iron and clay knife you want to build is here, please accept!" ”