There was a coal stove in the blacksmith shop, and the fire was raging. It was obvious that Zhang Laosan was also forging iron just now, and he put down his work when he heard their voices.
In his previous life, Qin Hai was a person with a wide range of interests. In order to explore traditional folk material processing techniques, he once worked as an apprentice in a blacksmith shop for a few days, so he had some understanding of the tools and rules in the blacksmith shop. He picked food from the ground
Pick up a pair of tongs, put the piece of shovel head that needs to be repaired into the fire, and start roasting it.
"Brother, do you really know how to temper?" Fatty also got in at some point and asked Qin Hai in a low voice.
It was midsummer, and the temperature in the blacksmith shop was seven or eight degrees higher than outside, almost like a steamer. Qin Hai already found it unbearable to stay in this room. Fatty, a person who is most afraid of heat, actually
He got in, completely ignoring the hot sweat flowing down his body like rain, which shows how seriously he takes this matter.
"Can you blacksmith, brother?" Qin Hai did not answer the fat man's question, but asked another question.
"I am the blacksmith." The fat man replied, "I made all these farm tools."
"That's great." Qin Hai said, "The shovel has a curled edge and needs to be re-forged. I'll leave this matter to you."
"...Okay." The fat man nodded calmly. It was already a great favor for someone to help with tempering. You can't let someone use a sledgehammer, right?
Qin Hai heated the shovel head to a certain temperature, took it out with tongs, and placed it on the anvil. The fat man, a blacksmith, also had a few brushes. He easily picked up a big hammer next to him and forged the shovel head.
Get up. Because it was just repairing the curled blade, the forging workload was not big. The fat man hit it with the hammer a few times, and Qin Hai told him to stop.
"Okay, can it be tempered?" The fat man pointed to a basin of water next to him and said to Qin Hai.
"Not busy." Qin Hai waved his hand and returned the newly forged shovel head to the stove to reheat it. His eyes stared at the color of the shovel head through the fire, waiting for it to heat up.
expected temperature.
"What are you waiting for?" Seeing Qin Hai's serious expression, Fatty couldn't help but feel solemn in his heart, and asked in a low voice.
"Heat treatment is not that simple. The metal must first be heated to Ac3, which is the temperature at which free ferrite is completely transformed into austenite, resulting in solid solution strengthening. Then it is taken out and slowly cooled in the air to make the grains finer.
Chemicalization and uniform distribution of carbides..." Qin Hai introduced the introductory knowledge of heat treatment to Fatty in a low voice.
"This... is too troublesome." The fat man directly refused the words and deeds of the postdoctoral fellow from the Academy of Sciences. Things like austenite and grains were too far away from him. He only cared about one thing: when can he see the quenched steel?
result.
Outside the blacksmith shop, Zhang Laosan was chatting with Mangu and the others while peeking at what was going on in the room. Seeing Qin Hai heating the workpiece unhurriedly, the teasing look on his face subsided slightly.
"What's the matter, Laosan?" Mangu felt the change in Zhang Laosan's attitude and asked in a low voice.
Zhang Laosan said: "This young man has some skills..."
"How about you?" Mangu said with a smile. He knew that Zhang Laosan always prided himself on his superb craftsmanship and liked to brag about himself. Now that he heard him say that a young man has some tricks up his sleeve, he couldn't help but take the opportunity to disparage him.
.
Zhang Laosan said insincerely: "Compared with me, he still has to wait 20 years... However, I don't understand what he means by doing this..."
At this moment, the short young man who went to find chemicals came back panting, carrying a cloth bag with several medicine bottles in it.
"Hey, where is the passerby?" the short man asked the tall man waiting outside the door. Qin Hai had not informed them of his name, so he could only refer to Qin Hai as "the passerby".
The tall man pointed his mouth towards the room and said, "It's inside, the iron was struck just now."
"I'm late?" The short man was a little depressed.
"It's not too late, the time is just right." Qin Hai replied in the room, "Have you got anything?"
"I got it all." The short man replied happily. He had traveled such a long way to find something on this hot day. It would be uncomfortable if he couldn't use it after he found it.
Qin Hai had already taken out the heated shovel head, but he did not put it directly into the water. Instead, he threw it into a pile of ashes nearby to keep it warm. This method is called tempering, which is also a few steps of heat treatment.
One of the major processes. Just now Qin Hai said that these farm tools need to be quenched, which is actually just a popular way of saying it. What he wants to do is to combine normalizing, tempering, quenching and other processes to achieve comprehensive heat treatment of the workpieces.
While the shovel head was being kept warm, Qin Hai took the medicine found by the short man and began to pour it into the quenching basin next to it. Precise weight control was obviously impossible. Qin Hai could only estimate based on experience.
Then pour the appropriate amount of medicine into the water and stir to mix.
"Young man, what are you doing?" Zhang Laosan had already entered the blacksmith shop at some point. Seeing Qin Hai busy, his curiosity suddenly arose.
Qin Hai turned around and smiled at Zhang Laosan and said: "I am preparing a quenching solution. This type of 65 manganese steel needs to be quenched with a trinitrate aqueous solution, which has the best effect."
"This is the first time I've heard of this." Zhang Laosan said in surprise, "Isn't quenching just water?"
"Master Zhang, have you ever heard of oil quenching?" Qin Hai asked rhetorically.
"I've heard of oil quenching..." Zhang Laosan said. The so-called oil quenching means using vegetable oil instead of water as the quenching medium. The quenching effect is different from that of water. Zhang Laosan knows that some ironware is quenched with oil.
The effect is better, but due to the high cost, it is not used much in practice.
Qin Haidao: "My theory is similar to oil quenching. Different materials and different uses require different quenching processes, which involve the use of different media. The trinitrate solution I use is most suitable for this kind of steel.
.”
"Three nitrates..." Zhang Laosan was completely frightened by Qin Hai. If Qin Hai was wrong, he was right; but if he was right, Zhang Laosan couldn't handle such things as three nitrates.
I have never heard of it. Could it be that this young man knows more than the old blacksmith himself?
"You will see the effect later." Qin Hai smiled and stopped explaining these issues. The scientific principles of material heat treatment are really not something that a folk blacksmith can understand. Of course, this does not prevent these folk blacksmiths from relying on instinct and years of experience.
Through practice, we can find heat treatment methods that impress even materials experts.
Qin Hai removed the cooled shovel head from the ashes and put it into the furnace for heating again. After it turned slightly red, he took it out and stuffed it directly into the prepared trinitrate solution.
"Hey!"
There was a clear sound of water, and a stream of water vapor rose from the quenching basin. Everyone in the room smelled a strange smell that was sour or salty. Qin Hai soaked the shovel head in the water for a minute or two.
, then took it out, threw it on the ground, and said to the fat man: "Okay, take it out and let the uncles try the blade."
"Is it really better?" The fat man was overjoyed. He didn't care that there was still some residual heat on the shovel head, so he carried it with his hand and left the house.
"Okay, you guys try it." The fat man shouted to several farmers.
"Okay?" asked the farmer named Mangu. He took the shovel head, looked at it carefully, nodded and said: "Well, it looks like the color is right. I just don't know if it is strong or not..."
"Can this shovel really break bricks?" asked a farmer next to him, just betting on his anger.
"This..." The fat man was a little unsure. He didn't know if the idea of breaking bricks was an exaggeration by Qin Hai. It was hard to harden the farm tools, but if the blades curled up after dropping a brick, it would be a loss of face.
"It's okay, let's chop it." Qin Hai also came out of the room, holding his hands and saying with a smile.
Hearing Qin Hai speak so confidently, Mangu became curious and wanted to see if the shovel was really as strong and durable as Qin Hai said. He put the shovel head on the wooden handle and found a piece from the side.
He knocked the half-cut red brick lightly with a shovel and asked Qin Hai: "Young man, can your shovel really cut bricks?"
"Cut it." Qin Hai was full of confidence. No. 65 manganese steel is a very widely used material. Later generations have conducted extensive research on the heat treatment process of this steel. If such a heat treatment is done, it will lead to something wrong.
Qin Hai can just wipe his neck and wear it again.
Mangu still didn't dare to make a mistake, so he hit the brick with the shovel several times, then raised it to look at the blade. When he saw that the blade was intact, he became furious and swung the shovel hard and struck the brick.
one time.
"impeach!"
The bricks broke into several pieces. Listening to the crunching sound of the shovel hitting the bricks, everyone except Qin Hai couldn't help but grin, thinking to themselves, this shovel must have something no matter what.
There was a small gap. Mangu hurriedly raised the shovel, wiped off the remaining brick dust on the shovel head with his hand, looked at it carefully, and couldn't help laughing: "Haha, it's really nothing!"
"let me see!"
"Let me see!"
Several other farmers and Zhang Laosan rushed forward to check the blade of the shovel. There was only a faint trace of friction at the place where the brick was smashed, and no damage or curling could be seen. It was pretty cool.
Everyone can feel the force that Gu used just now. The fact that he was unscathed under such an impact shows that the blade of this shovel is of excellent quality.
————————————————————
In the first week of the new book, the updates will be a little slower. I will update a chapter of 3,000 words a day, and I will work hard to save the manuscript. In the second week, I will try to achieve two updates a day. Please recommend, click, and collect the new book.