Xueba starts with change

Chapter 316 Recommendation Letters Are in Place
After being disturbed by the gang in the library, Chen Zhou was naturally embarrassed to talk to Yang Yiyi again.

With a light cough, he turned his attention back to the data in front of him.

With Yang Yiyi's previous preparations, the time Chen Zhou spent on the research on the surface modification of the intense pulsed ion beam was directly reduced by more than half.

He only needs to follow the normal general process and add a little bit of his own thinking to process the data quickly.

[The main reason for the formation of melting pits on the surface of the modified material is that under the action of high-pulse ion beams, the subsurface layer of 30SiMn3MoVA steel is heated first, resulting in carbides, grain boundaries, and crystals with thermophysical differences between the surface layer and the matrix. The low melting point sites such as chemical defects are first dissolved and erupted, and finally the surface of the material forms a melting pit. 】

While reading this passage, Chen Zhou's mind quickly flashed the relevant experimental data, as well as the surface microstructure and cross-sectional microstructure photos under the scanning electron microscope.

"The morphology characteristics of the surface treated by the intense pulsed ion beam are due to the fact that under the action of the intense pulsed ion beam, the surface layer of the material instantly accumulates high energy, and undergoes rapid heating, melting and cooling, which induces a stress field..."

"Ultimately, the surface layer of the material undergoes rapid and severe plastic deformation, forming the shape we see now."

Chen Zhou thought for a while, then opened the scanned photo sent by Dean Yang and took a look.

Immediately, Chen Zhou compared the experimental data again, and nodded slowly.

"When the intense pulsed ion beam bombards the surface of the material, its energy will be converted into heat energy in a very short time, and then the surface of the material will be melted, followed by rapid cooling."

"Under this condition, the formation of carbides and the precipitation of the second phase on the surface of the material will be inhibited, and finally the surface grains will be refined to form a remelted layer. The thicker the remelted layer, the higher the surface hardness of the material. "

"Under the conditions of various process parameters, as the number of pulses increases, the experimental results are within the expected range."

"Since that's the case, you can skip the part about the surface microstructure and go to the next step."

The next step that Chen Zhou thinks about is the analysis of corrosion resistance.

A good piece of steel not only needs to be hard enough, but also able to withstand corrosion!

According to the expected setting, Chen Zhou began to integrate and process the data.

Comparative analysis of the potentiodynamic polarization curves of 30SiMn3MoVA steel before and after intense pulsed ion beam treatment.

At the same time, the Tafel extrapolation method is used to fit the potentiodynamic polarization curve to obtain the variation of the corrosion potential and corrosion current with the number of pulses, and a list of fitting parameters is obtained.

Charts are the most intuitive representation of data and an essential part of data processing.

After taking a look, Chen Zhou just felt bored.

This kind of data processing, where everything is expected, is really simple, boring and unpretentious.

Inadvertently, she turned her head and glanced at Yang Yiyi, only to see that the girl was concentrating on the documents in front of her.

Chen Zhou glanced at what Yang Yiyi saw, ah, this girl is walking ahead of him again.

With a slight smile, Chen Zhou turned his head to look at the chart on the computer, and the speed in his hand began to increase.

You have to finish processing the data quickly, and catch up with Teacher Xiao Yang as soon as possible!
It is intuitively shown in the chart that compared with the original sample, the corrosion potential Ecorr after the high-pulse ion beam treatment has different degrees of positive shift.

This shows that the corrosion tendency of the treated samples is reduced.

The parameters fitted by the Tafel extrapolation method also show that after the high-pulse ion beam treatment, the corrosion current density Icorr of the sample becomes smaller.

This indicates that the corrosion rate of the treated sample is reduced.

On the draft paper, Chen Zhou began to write:
[The corrosion potential increases and the corrosion current density decreases, and the corrosion resistance of the sample after pulse treatment on the surface is enhanced. The highest corrosion potential is -641mV, the lowest corrosion tendency, and the lowest corrosion current is 6.91×10^-4mA/cm, The corrosion rate is minimal and the corrosion current is reduced compared to the pristine specimen. 】

[The data analysis results show that the samples after 30 pulse treatments have the best corrosion resistance. 】

This is the data analysis conclusion obtained under the condition of the first set of process parameters.

After completing one set, Chen Zhou rushed to the next set of experimental data without stopping.

The same method, the same thinking.

As time passed, the draft paper in front of Chen Zhou gradually piled up, and the unprocessed data became less and less.

Finally, Chen Zhou let out a long sigh of relief.

"The general rule has also come out."

Putting on a new draft paper, Chen Zhou habitually clicked twice before starting to write this rule.

[After the high-pulse ion beam treatment, the corrosion resistance of the sample is improved, but it does not increase with the number of pulses, and it has a certain repeatability. 】

Looking at the text he wrote, Chen Zhou thought for a while and continued writing.

[The first set of process parameters can be re-tested in the range of 30 to 33 pulse times; the second set of process parameters...]

This is Chen Zhou's suggestion, and it is also a small adjustment he can make.

This is also Chen Zhou's attitude towards experiments.

Of course, this is not the data given by Chen Zhou.

Instead, in the processing of experimental data, adjustments and speculations were made along the way.

The improvement of the corrosion resistance of 30SiMn3MoVA steel is the result of the joint effect of the grain refinement of the surface layer of the sample and the increase of the retained austenite content after pulse treatment.

This austenite, which is actually γ-Fe, is produced only after the high-pulse ion beam treatment changes the surface structure of the sample.

At the same time, the remelted layer formed after high-pulse ion beam treatment is not only hard but also corrosion-resistant.

Under the combined effect of these changes, the corrosion resistance of the sample surface is improved.

Thinking of this, Chen Zhou wrote his own reasons next to the experimental adjustment parameters given.

【...Within a certain range of pulse times, the thickness of the remelted layer will increase to a certain extent with the increase of the pulse times, which in turn improves the corrosion resistance of the material. 】

After finishing these, Chen Zhou looked relieved: "The data is finally done!"

Opening a new page of the word document on the computer, Chen Zhou began to organize the data processing results.

After a while, compress the file, send it by email, and it's done!

Next, is the experimental verification.

Chen Zhou stretched, ready to see how Yang Yiyi was doing.

Unexpectedly, when he turned his head, he saw Yang Yiyi looking at him with a smile.

Chen Zhou was embarrassed for a moment, and then raised his face: "Is the handsomeness on my face attractive to you?"

Yang Yiyi didn't speak, but made an "evil" expression.

Chen Zhou just wanted to raise his hand, but Yang Yiyi grabbed his arm first.

There is no way, the meat is in the hands of the people, so hurry up and beg for mercy.

Just as Chen Zhou thought, after Dean Yang received the processing results of the experimental data, he immediately arranged a new experiment.

The experiment is proceeding in an orderly manner, and Chen Zhou's life is also very fulfilling.

But what Chen Zhou didn't know was that a certain place was "quarreling" because of him.

The reason for the "argument" is also very simple. The joint recommendation letters of several academicians are already in place.

　Thanks to book friend cwjxqb for the reward of 500 starting coins, and thanks to book friend Xiahezhu for the reward of 139 starting coins.

　　I have a meeting outside today, and I am still working overtime to revise the report at night. There is only one update. Please forgive me, I will make it up later!

　　
　
(End of this chapter)