I started with a ship full of max-level veterans, and I'm just a complete noob.

No one responded.

The only sounds in the conference room were the muffled thud of water hammer from the heating pipes and the faint hum of the fluorescent light ballasts, as if the whole room was waiting for a starting move.

Jiang Ming didn't give the silence time to fester. He turned to face the blank area on the right side of the blackboard and picked up the shortened piece of white chalk from the chalk tray.

The chalk tip touches the black lacquer surface; the first symbol is the Greek letter τ, and the subscript reads "Persnabarro".

"Professor Zhou asked about the origin of the values ​​for the slip coefficient, so I deduced it from the bottom up."

Jiang Ming's voice was hoarse from working consecutive all-night shifts, and he spoke slowly, but his chalk strokes were extremely steady, with no hesitation between each letter and number.

"The nickel substrate is face-centered cubic, but the cerium-barium solid solution of the cathode coating is body-centered cubic at high temperatures. The principal slip system of body-centered cubic crystal is {110}⟨111⟩, the dislocation core width is narrow, and the Pearse barrier is an order of magnitude higher than that of face-centered cubic."

He wrote the first line: the ratio of dislocation climb activation temperature to melting point, with 0.4 times the melting point as the critical line.

Zhou Changlin picked up his pen again, and the nib followed the symbols on the blackboard, recording them synchronously in his notebook.

He stopped when he wrote the third equal sign.

Because what Jiang Ming wrote next was the explicit relationship between the mean square displacement of thermal vibration and temperature under the Debye model.

"When the temperature is above four times the melting point, the grain boundary dislocations gain sufficient thermal activation energy and begin to climb, and the slip coefficient is no longer a fixed value."

Jiang Ming wrote the exponential decay function in the second line, expressing the Perls stress as a continuous function of temperature, and taking the activation energy as the experimental range of body-centered cubic cerium-barium solid solution.

Ma leaned forward a bit, and the certainty that had been on his round face finally loosened.

He did indeed teach this stuff in his solid-state physics class at Leningrad.

But no one has ever linked it to the process parameters of electron tube cathode coating.

Jiang Ming continued writing the third line, substituting the ratio of dislocation density to grain boundary area into the expression for interfacial shear stress, and derived a complete curve of stress versus temperature.

Zhou Changlin stopped writing.

It's not because I can't understand it.

On the contrary, it's because they understand every step too well, and the logical chain is so self-consistent that it's unsettling.

"The slip coefficient used in the 1948 Soviet report was the average value of the linear fit in the range of room temperature to 200 degrees Celsius."

Jiang Ming wrote down the average value on the fourth line, and then marked the actual slip rate corresponding to the actual stress curve at 378 degrees Celsius.

The two numbers differ by a factor of 3.7.

"Using this average value to calculate the cooling step would underestimate the interfacial shear stress by nearly four times. Therefore, the Soviet standard set the eutectic trigger threshold at 0.2 percent, which was essentially a conservative upper limit calculated using incorrect mechanical parameters."

A line was drawn under the word "four times" with chalk, and white powder was applied to the yellowish rosin stains already present on Jiang Ming's cuffs.

Liu's lips moved slightly, as if he was about to speak, but then he closed them again.

He originally wanted to question the stability range of the body-centered cubic phase, but Jiang Ming had already added the phase diagram data in the fifth row.

Cerium barium solid solution is stable as a body-centered cubic structure above 600 degrees Celsius. When the temperature is lowered to 380 degrees Celsius, the phase transition has not yet occurred, and the body-centered cubic glide system remains effective.

This move was precise, as if they knew in advance what the other party was going to ask.

Zhou Changlin put down his pen, pressed his index finger on the last line of his notebook, and looked away from the blackboard, his gaze falling on Jiang Ming's face.

"Your derivation is mathematically closed and also makes sense in terms of physical diagrams."

His tone was completely different from what it had been ten minutes ago.

All arrogance was put away, replaced by the prudence of an experimental physicist when faced with a set of impressive data.

"But I have a question."

Zhou Changlin opened a blank page in his notebook, drew a question mark on it, circled it in a box, and then pointed to the dislocation density values ​​on the third line of the blackboard.

"Experimental data on the dislocation density of body-centered cubic cerium-barium solid solutions are not available in China, and even in the Soviet Union, it was only done on pure metals. What is the source of your value?"

When Ma heard this question, his eyes lit up.

This is indeed the weakest link in the entire derivation chain.

If Jiang Ming cannot provide a credible source, the preceding deductions of the five elements will remain in vain.

Jiang Ming did not evade the question.

He picked up the chalk and added a set of inequalities at the end of the fifth line.

"I really can't do direct measurements; there are no transmission electron microscopes available in China."

He admitted it readily, without any attempt to hide anything.

"However, dislocation density has upper and lower bounds. The upper bound is determined by the grain size. The grain size of my electrophoretic coating can be measured with an optical microscope. The actual measurement is between 0.8 and 1.2 micrometers. The corresponding upper bound of dislocation density can be calculated using the Holpage relation."

He wrote the inverse calculation formula and substituted the values ​​on the blackboard.

"The lower bound is determined by the annealing temperature. The residual dislocation density after annealing at 380 degrees Celsius for 30 minutes has experimental references from the Soviet Union in 1950 for iron-based alloys, and the difference between body-centered cubic systems is no more than half an order of magnitude."

The upper and lower bounds are circled, and the actual value falls in the middle.

After substituting the stress into the calculation, the result shows a variation of less than 15%, which does not affect the conclusion that the eutectic threshold has shifted upward to more than 1.6%.

Zhou Changlin stared at the set of inequalities for nearly half a minute, the pen cap silently spinning in his left palm.

He drew a second question mark in the blank space of the notebook.

This time, I didn't draw a square or border; I just made a light line and then closed the notebook.

The movement was so subtle that only the groom sitting next to him noticed it.

Ma Gong didn't speak, but he read a judgment from Zhou Changlin's face.

I passed math.

Xu Chongwen sat in the audience, his hands folded above his briefcase, his face gradually turning from stiff to an indescribable ashen white.

He was initially convinced that Jiang Ming could not possibly provide a self-consistent derivation without the support of Soviet literature.

But the six lines of formulas on the blackboard, plus the five supplementary formulas, had already shattered his judgment into pieces.

When Zhou Changlin spoke again, the accent he had picked up from Leningrad had faded considerably.

"I haven't found any logical flaws in the theoretical derivation yet, but no matter how beautiful the things on the blackboard are, they're still just words on paper."

He tightened the pen cap, put it back in his breast pocket, and placed his hands flat on the table.

"Comrade Jiang Ming, could you show me the actual test data? How many hours of continuous recording do you have on hand regarding the emission current stability curve of the coating after prolonged high-temperature operation?"

The moment those words were spoken, the atmosphere in the conference room changed.

Factory Director Zhang loosened his grip on the enamel mug.

Because he could tell that Zhou Changlin wasn't nitpicking, but rather seeking confirmation.

A person who has transformed from an inquirer to a seeker of verification has already accepted the theory in their mind and only needs data to complete the final confirmation.

Wu Hanzhang glanced at Jiang Ming, his fingers already touching the kraft paper cover of the 23-page process report on the table.

Jiang Ming nodded and turned to signal to Wu Hanzhang.

Wu Hanzhang handed the report to Zhou Changlin with both hands, the data column on the fourteenth page facing upwards.

The static emission current of the B01, 285 microamps, was drawn out in red double circles, directly opposite the pencil mark of 221 microamps in the Soviet manual for the same model.

Two figures are about to come into the expert panel's view simultaneously.