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

Two days later, Furnace No. 3 completed the third round of silicon zone purification. After Lao Sun and others lowered the furnace body to the maintenance temperature, they removed the protective cover and pulled out the two silicon carbide rods one by one from the chuck.

He first checked the contact marks left by the double-sided compression, then took a micrometer to measure the free length of the nickel-chromium alloy spring. The reading differed from the initial installation record by 0.3 millimeters.

Old Sun remeasured it three times, then handed the calipers to Fang Xudong, his face gradually darkening.

"It was shortened by 0.3 millimeters. According to the original compression amount, the preload has dropped by 20%. This batch of yarn climbed faster than we expected at high temperatures."

Fang Xudong took the spring, filled in the measured value into the maintenance record, and arranged the three sets of data from the initial installation, the end of the second installation, and the end of the third installation in the same column. The change in the free length of the spring has formed a continuous trend.

Old Sun gently ran a triangular file across the contact surface of the copper foil. The file brought up a layer of dark red powder. The originally smooth copper foil had oxidized and changed color, and the edges were much thinner than when it was first installed.

He spread the copper foil on a piece of white paper and circled the two dents where the pressure was heaviest with a pencil.

"As the spring retracts, the copper foil becomes thinner. The clamps may still appear to hold it in place, but the actual conductive area is constantly changing. Over time, the active contact resistance will eventually return."

Jiang Ming took the temperature control paper tape off the recorder, laid out the 1420-degree constant temperature range of the first and third times side by side, aligned it with the time reference, and checked it frame by frame.

The first fluctuation remained around ±0.2 degrees, while the third fluctuation expanded to ±0.25 degrees. The feedforward table could still cover this drift, but the degradation trend was already written on the paper tape.

Temperature control networks can correct slowly changing input power, but they also hide the continuous aging of mechanical contacts within the compensation amount. Only when the correction range is gradually filled will the furnace temperature curve become out of control again.

Jiang Ming wrote down three sets of data—spring free length, end equivalent resistance, and constant temperature fluctuation—into a kraft paper notebook and estimated the creep rate based on the existing high-temperature operating time.

"Around one hundred hours is exactly two to three rounds of purification. After that, every time the time reaches this point, the spring and copper foil are replaced, and the removed parts are individually numbered to continue measuring the free length and degree of oxidation."

After listening, Lao Sun opened the spare parts box, took out the reserved nickel-chromium alloy wire, and wrapped it on the steel mandrel to rewind the double-sided springs.

His thumb pressed down on the alloy wire as he fed it forward, checking the spacing with calipers after each turn. When he encountered a slightly wider gap, he would retract the mandrel and tighten it again until the free length and pitch of both springs fell within the range of the drawing.

Before removing the old parts, Fang Xudong measured the end resistance. After the new spring and three layers of copper foil were put back into the clamp, he measured the two connection ends in turn and asked Lao Sun to loosen and tighten them three times.

The three sets of readings returned to the initial installation level, and the dispersion after disassembly and reassembly was also brought into the maintenance standard. Fang Xudong wrote "replacement effective" at the end of the record, and then put the old spring into the sample bag marked "third time".

The furnace could continue to run, but the pressure in Jiang Ming's heart did not decrease with the readings. He stared at the remaining nickel-chromium wire in the spare parts box. Based on the current consumption, he would need to prepare two rounds of replacement parts after six consecutive purifications.

He turned to a new page, first drawing out two long-term schemes: molybdenum wire and tungsten wire, and then marking the elastic coefficient, winding radius, preload, and high-temperature brittleness as items awaiting verification.

Molybdenum and tungsten can withstand higher temperatures, but their elastic parameters and processing performance are quite different from those of nickel-chromium alloys. Directly copying the existing spring dimensions will only cause the force on the chuck to be reversed.

The second direction focuses on the heating structure itself. Jiang Ming drew the relationship between the coil, furnace tube and silicon material, and wrote down the radio frequency induction heating and power generator.

This approach bypasses the mechanical connection between the silicon carbide rod and the metal clamp, and the cleanliness of the furnace can be improved. The cost is a high-power radio frequency generator, a matching network, and a redesigned shielding structure.

When Wu Hanzhang entered the furnace room, Jiang Mingzheng had already divided the two directions into two columns: long-term and short-term. He flipped through the spring spare parts consumption record and added the monthly usage of nickel-chromium alloy wire and copper foil to the resource requirements page of the pre-research plan.

"We'll rely on replacing the springs for now. We'll schedule the radio frequency heating once the pre-research funding is in place. We can inquire about the supply of molybdenum wire and tungsten wire first, and then discuss the clamps once we get the samples."

After he finished speaking, he pushed the resource page back into the plan, his gaze lingering on the 100-hour replacement cycle for a moment. He clearly understood that this maintenance method could only buy time for Furnace No. 3.

In the evening, Comrade Song walked into Research Room 502 with a military-issued envelope. The source column in the handover book read Aksai Station No. 3, and the sealing date was only four days ago.

Jiang Ming checked the seal, then tore open the envelope along the edge. Lu Qinghe's second letter was only two pages long, beginning with a list of monitoring results from the past week.

Station 3 captured eleven pulses in the 22-24 GHz band. Although the duration was still short, the frequency of occurrence had changed from sporadic to continuous occurrence over several days.

Next to the last two records, Lu Qinghe drew the pulse arrival time separately. Several sets of intervals of varying lengths were drawn, and the pulses showed grouping characteristics. Based on this, the duty team suspected that the signal contained an internal coding structure.

The last line of the letter was written in bolder text than the preceding lines.

"If this is encoding, the other party may have already moved from device testing to network communication."

Jiang Ming took out the K-band fragment summary from the Aksai direction, placed the two pages of military records side by side, and noted that the field networking test mentioned in the fragment would take place three months later, with the time window covering the current month.

From sporadic radiation to eleven captures per week, and then to pulse grouping at unequal intervals, these three changes correspond to the time schedule, but the current recording accuracy of Station 3 is still insufficient to support the final judgment.

He pulled out the military reply paper and asked the duty team to record and retain each pulse train completely, improve the pulse interval recording accuracy to milliseconds, and try to distinguish whether the pulse width within the train changes with the grouping.

When writing the requirements for copying reports, Jiang Ming changed the original routine attention to an increased level of urgency, and added another point: the original recordings should be sealed first, and the analysis conclusions should be transmitted separately from the original records.

Comrade Song took the sealed reply, checked the recipient code, put it in his personal folder, turned and left the research room. The footsteps outside the door quickly disappeared into the end of the corridor.

At night, the light from Lab 502 shone on the windowpane. To Jiang Ming's left were the temperature control paper tape and spring replacement records for Furnace No. 3, in the middle were the letter from Theodore von Kármán and the outline of his third reply, and to his right were the letter from Lu Qinghe and the K-band pre-research plan.

Silicon materials determine how far the device development path can go. The third question in Pasadena leads to another academic path, while the pulse coming from the northwest border is urging the 24 GHz pre-research to accelerate.

Old Sun pushed the door open and placed the newly ground spare spring on the side of the worktable. The box cover made a crisp sound when it was closed. Jiang Ming raised his hand and pushed it next to the maintenance record of the No. 3 furnace.

At the next table, Fang Xudong was updating the overall schedule. The next round of silicon purification was scheduled for the day after tomorrow, the preparation node for silicon single crystal growth was set for two weeks later, and the third demonstration meeting of the Fifth Academy was also squeezed into the same period.

He readjusted the three progress lines using red and blue pencils.