Zheng Yuan's idea is good, but some gaps cannot be made up by that skill.

When the gap reaches an insurmountable point, no amount of tricks will yield the same result.

It's like the eggs in the world can't smash a hard stone, this is already an essential gap, and it can't be made up by quantity at all.

Unfortunately, Zheng Yuan encountered such a situation.

When the two machetes collided, the force transmitted from the wrists paused, and the slight slipping action made intentionally was not completed.

Zheng Yuan sighed in his heart and was stuck, what is the situation?

A bad feeling poured into Zheng Yuan's mind.

Looking sideways, the "divine soldier"-level machete he had just created had been crumbled on the edge.

After removing his own machete, the blade of the machete below was still as smooth as a mirror, and there was not the slightest damage.

Zheng Yuan's eyes widened, looking at the gap in his knife, this ...... Is this the gap?

Wei Minsheng was also afraid that he would blow this hard-won "technician" too badly and lose his self-confidence, so he said to Zheng Yuan: "Do you know where the gap is? ”

"Where is the gap?" Zheng Yuan seemed to have returned to the time when his father taught him to observe the heat, and he asked like this.

Zheng Yuan is constantly learning, accumulating experience, and constantly improving his forging ability in the process of constantly finding gaps.

Originally, I thought that my forging level had at least reached the first-class level, but now it seems that this gap is not a star and a half.

Moreover, when I heard this, it seemed that I was deliberately pointing out myself.

There is no order to learn, and the one who achieves is the first.

Since his skills are not as good as others, there is nothing to say.

If the person in front of him can really tell him where the gap is, it can be regarded as a half-master friendship.

Thinking of this, Zheng Yuan put down the machete in his hand, bowed to the ground, and said, "Please also ask Mr. for guidance." ”

After Wei Minsheng asked Zheng Yuan to get up, he slowly led him to the place where the steel had been heated earlier.

Then he said to Zheng Yuan: "There are still many problems with your quenching method, so you can't make the steel achieve the best hardness and toughness."

I see that you didn't anneal before quenching. ”

"Annealing?"

"As far as I know, in order to achieve the hardness of the machete I showed you, you have to go through four processes.

The four processes are annealing, normalizing, quenching, and tempering.

In the operation you just had, only one quenching process was used, so although the hardness went up, it lacked a kind of toughness, and it was easy to crack when it encountered a strong bump. ”

"Four crafts?" Zheng Yuan searched hard for these things in his memory, but he didn't think of anything related to them.

"These four processes are necessary to ensure that they are in the best possible condition in the end, and they are all indispensable.

This annealing is the first process, after the machete is formed, the whole machete should be heated to a proper temperature, and this temperature should be maintained for a period of time, and then the temperature should be slowly lowered. ”

"What's the purpose of doing that?"

"The purpose of this is to heat the machete evenly throughout the machete, so that its internal structure is at or near equilibrium, ensuring consistency and overall strength across all materials.

Without this process, some small gaps in the inside of the machete cannot be eliminated, and no matter how perfect the quenching is, these defects cannot be compensated.

The existence of these tiny gaps is the reason why they are easily broken. ”

"I see!" Zheng Yuan recalled the process of forging in his heart, and only then did he understand why the same quenching method relied on luck to create a "divine soldier".

It turned out that in the process of continuous heating and hammering, sometimes the annealing conditions were met inadvertently, which improved the overall strength of the blank and laid a solid foundation for the later quenching.

"The second process is normalizing, in which the machete is heated to a proper temperature and then placed in the air to cool naturally.

The effect of normalizing is similar to annealing, except that the internal structure is finer, resulting in better cutting performance and a sharper cutting edge. ”

These two seemingly simple methods, I didn't expect to achieve such an effect, how did they know?

Zheng Yuan held back the shock in his heart and tried to write down all the details that Wei Minsheng said.

"The third process is tempering, which is a treatment process after the quenching process.

The tempering process requires the quenched machete to be heated again to a temperature below 710 degrees Celsius for a long period of time and then cooled.

After the tempering process, the brittleness of the machete is further reduced while maintaining its hardness.

When you processed the machete you created, you only used the quenching process, and the other three processes were not used at all.

The overall strength of the machete processed in this way is naturally greatly reduced, so it cannot be compared with the machete created using the complete process.

And, even in the quenching process you use, there are still some problems. ”

"Still have problems with the quenching process?" Zheng Yuan said in surprise.

"Yes.

The material I've given you, if you want to get the best performance, it's quenched and heated, the optimal temperature is 780 to 830 degrees, and you heat it to almost 1000 degrees.

As a result, the cooling time becomes longer, the best strength cannot be achieved, and even the internal stress is caused by uneven thermal expansion and contraction inside, which causes slight deformation and internal cracking of the machete. ”