Chapter 1404 Selective Absorption Metamaterial

The 606th Institute itself does not have the ability to develop aviation materials. Therefore, like some other general institutes responsible for system design, it will propose a series of key indicators based on model requirements, and then assign or bid a unit to undertake the development work.

Just like other Party Bs, although the latter will attach a test report along with the materials, it is just completing the task after all, and the content in the report obviously cannot be all-encompassing.

Generally speaking, it will only include various conventional properties and relevant indicators proposed by Party A in the development requirements.

Because the use of this coating to block infrared signals was not considered when the WS-10G was first designed, in the subsequent acceptance stage, the thermal insulation performance and overall infrared emission characteristics of the new material were only examined according to convention.

In a way, these two metrics are actually the same thing.

As for the results, while they are indeed slightly different from the old version, they are still in the same order of magnitude.

And the test process just now has also proved that the macro temperature shown by the engine is not much different from Liu Yongquan's prediction, which means that there was nothing wrong with the previous test process.

It's simply that this material exhibits some properties that have not been noticed before.

Liu Yongquan soon followed Yang Wei to the confidential office of Factory 132 and contacted Researcher Peng Wenzhi at the Materials Research Institute who was responsible for the development of new coatings.

"Lao Peng, it's me, Liu Yongquan."

After the call was connected, he introduced himself and got straight to the point:

"There are some issues with the infrared emission properties of the HDK305 coating..."

Although the test of aircraft No. 2003 started early in the morning, everyone had already gone through several rounds of testing in the workshop. In addition, due to considerations of life and reliability, the engine could not be started and stopped too frequently, so it was actually almost sunset at this time.

Peng Wenzhi was just about to get off work when he suddenly received a call from Party A saying that there was a problem with his product. His blood pressure almost dropped instantly and he quickly asked:

"what is the problem?"

Liu Yongquan hesitated:

"It's not very clear at the moment, but the results show that the thermal signal intensity is extremely low, only about half to a quarter of the calculated value, and it is not stable at a certain ratio, it is like a gate..."

"..."

He spent a few minutes recounting what had happened that day.

Peng Wenzhi also felt confused after listening to it:

"how is this possible?"

He quickly returned to the computer, turned on the screen, and quickly found the test report:

"Didn't we measure the optical and thermodynamic properties during the acceptance inspection? If I'm being honest, the thermal conductivity is a few percentage points higher than the previous generation of products?"

At this point, he suddenly paused:

"Wait, you didn't say temperature... So you specifically measured the reflection... or absorption spectrum?"

There was a hint of displeasure in his tone.

In theory, if Party A wants the material to have certain optical properties, then it can simply state this in the task requirements.

Even if you want to ensure that everything is foolproof, you can just state it directly in the contract and have the inspection report issued by a third party mutually recognized by both parties.

Such silent appointment of someone else for testing usually shows extreme distrust of the other party.

It would be fine if you didn't trust me, but why did you make a special phone call to say it?

We are all in the same system and we see each other every day. How can we work together in the future?

However, Liu Yongquan was full of curiosity at the moment and did not notice the subtle changes in the other party's tone:

"I'm not measuring the spectrum... I'm currently at Factory 132, using an infrared imaging system and stimulated interferometry to make observations."

Peng Wenzhi was stunned again, and then realized that there was a misunderstanding during the communication, so he turned his attention back to the abnormal situation mentioned by the other party.

"Infrared imaging and stimulated interference are not strict methods for solid material testing. If you really want to obtain detailed infrared light characteristics, you still need to do spectroscopy..."

He had worked in laboratories for the first half of his life, and was helpless about the occasional creative ideas that engineers came up with.

But Liu Yongquan's response also highlights a sense of justification:

"Even if stimulated interference spectroscopy is not as accurate as optical spectroscopy, it's impossible for such a large error to occur, right?"

This sentence was well-reasoned and left Peng Wenzhi speechless for a moment.

But it also gave him new inspiration:

"Lao Liu, when you were measuring, was the target exposed to the atmosphere?"

Liu Yongquan was somewhat helpless:

"We are testing an entire aircraft, and we can't put it in a vacuum tank... the cost is too outrageous, and it doesn't fit the actual working environment."

"That's right... there is indeed a theoretical possibility."

Peng Wenzhi explained:

"The atmospheric window bands for infrared detection are 3-5 microns and 8-14 microns. The parts other than these are easily absorbed by carbon dioxide and water vapor. Therefore, if a material has a high absorptivity precisely in these two window bands, or one of them, and has high transmittance in all other bands, then low infrared signals and high heat dissipation capabilities can be achieved at the same time on a macro scale. This cannot be found in our previous infrared emission characteristic tests that were not divided into frequency bands..."

At first, he looked as if he had suddenly realized something.

However, when it comes to the latter part, I am a little skeptical:

"But this kind of material is so ideal that we usually only dare to write some relevant content in the 'Future Work Outlook' section at the end of the paper, otherwise it will be easily regarded as bragging..."

"Our hospital shouldn't be that powerful, right?"

Liu Yongquan was so overjoyed at this time that he didn't care about these things:

"According to you, as long as this coating is applied to the entire surface of an object, the target will completely disappear from the field of view of the infrared imaging system?"

As he said this, he subconsciously looked at Yang Wei who was waiting for the communication results.

The latter's eyes also lit up at this time.

If he could achieve dual stealth of infrared and radar signals, then Project 20 would be a complete success for him.

However, Peng Wenzhi was not as optimistic as the other two:

"In principle, this is true... But first of all, the mechanical properties and coating properties of this material are average, and a large amount of additives are needed to adhere to the surface of metal or composite materials. It's okay to use a small amount now, but if you really want to cover the entire aircraft, the cost and weight will probably be a problem."

"Of course there is always a way to overcome this. More importantly, we'd better first make sure that this characteristic is not an isolated case..."

Liu Yongquan frowned somewhat awkwardly:

“When the chemical composition is determined, can the material properties be an exception?”

Peng Wenzhi laughed immediately:

"It's hard to say... Although materials science has made great progress in many aspects, it is still essentially a more efficient alchemy, unless..."

His words stopped here.

"Unless what?"

Liu Yongquan couldn't help but ask.

“Unless you can predict the macroscopic properties of a material to some extent based on how the microscopic particles are arranged.”

This time, Peng Wenzhi's tone was full of seriousness:

"So I plan to contact the Torch Laboratory. Academician Chang and his team might be able to do it..."

When Liu Yongquan heard Chang Haonan's name, he suddenly felt like he had "gone around in a circle and returned to the starting point."

He smiled bitterly and shook his head, then looked at the calendar on the table next to him.

2009 1 Month 16 Day.

"Mr. Chang is probably not in the capital right now."

According to the plan, the "Xuanniao" hypersonic aircraft will soon conduct its fourth and fifth consecutive flight tests. At the same time, the "Thousand Eyes Sky Survey" radar network proposed by Chang Haonan has also been deployed, and will take this opportunity to verify its monitoring and early warning capabilities for hypersonic targets in nearby space.

Of course, these details could not be explained clearly to Peng Wenzhi on the other side.

"Let's not worry about that for now..."

Peng Wenzhi spoke very quickly:

"If this artificially designed metamaterial can become a reality, it may be a game-changer for the entire material science..."