Development of productivity started in 1981

Chapter 259: Big Construction VI (Nuclear Weapons)

While assisting in the construction of commercial nuclear reactors, Wang Jiankun also did not neglect research on nuclear weapons.

Before 1984, the internationally recognized nuclear weapon states (NWS) were the United States, the Soviet Union, Britain, France, and China.

Other countries that possess nuclear weapons but have not publicly acknowledged it include India, Israel, and South Africa.

The United States was the first country in the world to complete the manufacture of nuclear weapons (the first to study nuclear weapons was Germany), and its first nuclear test was on July 1945, 7.

By the end of 1984, information collected from various sources showed that the United States had approximately 23000 nuclear warheads, covering land-based missiles (Minuteman III), submarine-launched ballistic missiles (Trident C4) and strategic bombers (B-52).

The Soviet Union conducted its first nuclear weapons test on August 1949, 8. As of 29, its nuclear arsenal consisted of approximately 1984 nuclear warheads, including the SS-39 "Satan" intercontinental missile and the Typhoon-class nuclear submarine.

The first British nuclear weapon test was on 1952 October 10 (Operation Hurricane).

However, Britain's national strength declined significantly after World War II, and its nuclear power relied on American technology. By 1984, it had about 350 nuclear warheads equipped with Polaris submarine-launched missiles.

France's nuclear test was even later. According to some secret information, it was misled by the United States during its nuclear weapons research, which led to serious errors in calculating the mass of the nuclear ball. Therefore, it was not until February 1960, 2 that it completed its first nuclear weapon test.

However, he did not join NATO, but independently developed the "three-in-one" nuclear force, so his nuclear arsenal is complete, including Mirage IV bombers, M4 submarine-launched missiles, about 360 warheads, and their use is not restricted by the United States.

China's first nuclear weapons test was on October 1964, 10, with the internal code name "Project 16".

It mainly relies on land-based missiles (Dongfeng-4/5), with about 300 warheads, and pursues a "minimum deterrence" policy.

India's first nuclear weapon test explosion was on May 1974, 5 ("Smiling Buddha"), declared to be for "peaceful purposes".

However, its industrial capacity is not strong enough. Information collected from various channels shows that only the plutonium bomb test has been completed, and the uranium bomb test has been slow due to the shortage of high-speed centrifuges.

Israel's nuclear program started very early. In the 1950s, France provided technical assistance to help it build the Dimona reactor (Negev Nuclear Research Center).

The current consensus in the intelligence community is that it possesses 80-200 nuclear warheads, with carriers including Jericho missiles and F-16 fighter jets.

South Africa developed gun-type uranium bombs in the 1970s and in 1979 it was suspected of cooperating with Israel in the "Vela Incident" nuclear test.

In addition to the above eight countries that already possess nuclear weapons, there are two countries that are on the nuclear threshold, namely Pakistan and North Korea.

A few years ago, the United States tacitly allowed Pakistan to advance its nuclear program, which is currently in the stage of building a test reactor and conducting preliminary nuclear weapons research.

As for why the United States supports Pakistan, a Muslim country, in developing nuclear weapons, we have to mention that Iran stabbed the United States in the back, causing the United States' sphere of influence in the Middle East to shrink sharply and fall at a disadvantage in the confrontation with the Soviet Union.

Therefore, in order to contain Iran, the United States turned to support Pakistan.

North Korea started researching nuclear weapons very early. As early as 1956, the Soviet Union signed the Nuclear Energy Cooperation Agreement with North Korea, providing it with support for nuclear physics research and assisting in the establishment of the Nyongbyon Nuclear Scientific Research Center.

In the 1960s: The Soviet Union assisted in the construction of the IRT-2000 research reactor (2 MW thermal power) for isotope production and scientific research.

But later, North Korea's national strength could not support such resource-intensive research, so progress was very slow.

At the same time, the Soviet Union itself did not want North Korea to acquire nuclear weapons so quickly, so its support became increasingly weaker.

Therefore, it was not until 1980 that North Korea began to build a 5 MW graphite reactor (capable of producing weapons-grade plutonium) at the Yongbyon nuclear base.

As for why North Korea did not choose the uranium bomb with a lower threshold, but instead aimed at the plutonium bomb right from the start, we have to talk about the difference between the two.

Although the manufacturing threshold of uranium bombs is low, for example, South Africa has used this technology to produce gun-type nuclear weapons, but it is very challenging for a country's electricity supply and high-speed centrifuge manufacturing capabilities.

North Korea is a weak country. Although the military-first policy can mobilize national resources to the greatest extent, a single uranium bomb requires 90 kilograms of uranium 235 with a concentration of more than 52%.

To extract so much uranium, the amount of electricity consumed is extremely huge. Half of North Korea’s electricity is used to refine uranium 235, and it can only barely produce a few uranium bombs.

The raw materials required for a plutonium bomb are an order of magnitude less. Its critical mass is about 10 kilograms (bare sphere), which can be reduced to 5 kilograms after adding a neutron reflection layer.

In addition, plutonium bombs have great potential.

It can be miniaturized, and the implosion design can compress the plutonium core to the size of a baseball (modern tactical nuclear warheads weigh only 100-200 kg).

The equivalent is controllable and the plutonium bomb equivalent can be flexibly adjusted (from kilotons to millions of tons).

Of course, plutonium bombs are not all advantages, they also have disadvantages.

First of all, the technology is complex. The implosion requires nanometer-level symmetry accuracy (error <1%) and the detonation timing error is <10 nanoseconds. This is a great test of scientists' abilities in design work.

Secondly, the material is sensitive. Plutonium is easily oxidized and spontaneously combusts, and requires special treatment, such as nickel plating or argon packaging, which requires research on related technologies.

Finally, there is a radioactive risk. The mixed plutonium-240 has a high spontaneous fission rate, which can easily lead to "duds", so it needs to be precisely purified. Although the purified mass is small, the centrifuge speed and isolation membrane manufacturing technology are higher than those for purifying uranium-235.

After comprehensively considering the advantages and disadvantages of the two technical routes, North Korea chose the plutonium bomb route, which is more technically difficult but requires less resources and industrial production capacity.

Wang Jiankun's choice was also the plutonium bomb route. Compared with the uranium bomb, the shortcomings of this technical route were no longer disadvantages in front of Wang Jiankun's ability.

As early as when he was manufacturing the 3-megawatt helium-cooled nuclear reactor, he had considered the issue of developing nuclear weapons in the future.

Therefore, each nuclear reactor that is using nuclear fuel balls to generate electricity is continuously producing nuclear waste containing plutonium.

So when he began working on the plutonium bomb in 1985, he had plenty of it at his disposal.

However, nuclear weapons testing is a systematic project and has also attracted worldwide attention. Therefore, in order to have a safe period of development in the future, Wang Jiankun needs to make comprehensive considerations.

Although he can use his super powers to extract ultra-high purity plutonium-239 from nuclear waste, the demand for this element will be extremely huge in the future, so conventional extraction industrial capabilities must be developed.

Because the conventional production of helium-cooled nuclear reactors is more complicated and more difficult to mass produce.

Therefore, the future source of plutonium-239 will not be able to rely on the nuclear waste from the helium-cooled nuclear reactor created by Wang Jiankun with his superpowers. It is necessary to build one or several graphite reactors or heavy water reactors.

Of course, this type of reactor is mainly used to produce plutonium, so its power does not need to be that large.

Taking into account the construction period and difficulty, Wang Jiankun decided to refer to the graphite pile of North Korea.

North Korea's Yongbyon 5MW reactor is a first generation nuclear reactor using Soviet technology.

In late March, Wang Jiankun disguised himself and entered North Korea.

Then, with the help of local Quanjiezhen agents, they quickly arrived at the Yongbyon reactor site.

The entry process was not as complicated as Wang Jiankun had imagined. The security of the reactor was loose on the outside but tight on the inside.

The perimeter guards were few in number and often in a daze.

After observing for two days, Wang Jiankun disguised himself as an internal technician who often went out.

At the gate, the guard simply glanced at the ID and let him in. Wang Jiankun imitated the demeanor of the internal technician the entire time, looking down when handing over the ID, and flicking off the non-existent dust with his hand when taking it back.

Because the guard's rank is lower than the technician, the technician looks down on the guard.

After entering, Wang Jiankun walked quickly along the periphery of the reactor. With his superpower projection range fully activated, he could avoid most surveillance. While walking, he projected the entire internal situation of the reactor into his mind.

At this time, the equipment installation of this reactor has been completed, and North Korean researchers are debugging the equipment one by one.

Wang Jiankun didn't stay inside for long. After more than 30 minutes, when he had projected the inside and outside of the reactor into his mind, he went home.

After returning, he began to build the first generation of graphite reactor at the Ningdi base.

The first is infrastructure construction.

Because more reactors of this type would be built in the future, he used his superpowers to build them while letting the technicians study the technical information he provided.

The Ningdi area is actually on the edge of an earthquake zone, so for future safety, he has taken more preventive measures in infrastructure projects.

For example, the earthquake-resistant foundation is 10 meters high, which is 7 meters thicker than North Korea’s 3-meter foundation.

The biological shielding wall (a reinforced concrete basement with a channel for pre-buried pipelines) is 5 meters thick, 3 meters thicker than the reactor in North Korea.

He used a lot of super powers to assist in the outer concrete foundation and shell, excavating tens of thousands of cubic meters of earth every day.

Then graphite bricks are manufactured.

The purity of this graphite brick must reach three nines or above.

While using super powers to manufacture, Zhizi also designed the corresponding equipment and asked relevant research institutes to study and manufacture it, so as to provide graphite bricks for the future replication of this reactor.

A total of more than 6 graphite bricks were manufactured, and then workers were directed to stack them into a cubic structure with many holes inside for placing fuel rods and control rods.

Metallic uranium fuel rods are manufactured in uranium raw material factories and are natural uranium clad in aluminum and magnesium alloy.

Light water is used for cooling, and the cooling pipes are parallel to the fuel channels. After the reactor is started, the heat generated by the reaction will be brought out of the core.

Control and safety systems are similar to those of helium-cooled reactors.

Control rods are made of boron carbide and are inserted into the core to adjust reactivity.

The emergency shutdown system causes the gravity-driven control rods to fall rapidly, terminating the chain reaction.

In addition to graphite and manpower rods and control rods, the core also has fuel processing equipment, radioactive waste treatment equipment, neutron detectors, and temperature and pressure sensors.

Wang Jiankun first used his super powers to manufacture these devices, and then extracted and sorted out the technical information and gave it to the relevant research institutes.

Because most of the work was done by Wang Jiankun using his super powers, this reactor dedicated to the production of weapons-grade plutonium-239 was completed in just three months.

By July, a series of tests were completed thanks to the day and night efforts of Wang Jiankun and a large number of technical personnel.

On August 8, this 1-megawatt graphite reactor was officially started.

In Wang Jiankun's mind, metal rods made of natural uranium (containing 0.7% uranium-235) were inserted into the core, and then a chain reaction began spontaneously.

The fast neutrons produced are slowed down by the moderating effect of graphite, and the uranium-238 in the natural uranium metal rod begins to capture these slow neutrons, and after a series of complex reactions, it turns into another element, plutonium.

In order to control the production of more plutonium-239 and reduce the production of plutonium-240 with a high spontaneous fission rate, the fuel rods must be replaced every one and a half months.

After the spent fuel is removed from the reactor, it is left for about six weeks to reduce its radioactivity.

The cooled fuel rods are then cut and soaked in concentrated nitric acid to dissolve the uranium, plutonium and fission products to form a mixed solution.

The uranium and plutonium are then extracted using **tributyl phosphate (TBP): TBP/kerosene is added to the nitric acid solution, the uranium and plutonium are extracted into the organic phase, and the fission products remain in the aqueous phase.

Plutonium is separated from the organic phase using dilute nitric acid or a reducing agent (such as Fe) to form a plutonium nitrate solution.

Repeat the extraction steps to remove residual fission products (such as cesium-137, strontium-90).

After chemical extraction.

Convert plutonium nitrate solution into plutonium dioxide (PuO).

PuO is reduced with calcium or magnesium in a high-temperature fluoridation furnace to obtain plutonium metal ingots (purity > 95%).

By September, the above advance work was basically completed.

Wang Jiankun obtained 6 kilograms of plutonium-95.4 with a purity of 239% extracted by conventional methods.

At this point, the manufacture of the plutonium bomb is mostly complete.

Then comes further processing.

The first is to cast it into high-density α-phase plutonium metal (density 19.8 g/cm) to adapt to the nuclear charge implosion design.

Because plutonium reacts very easily with oxygen, the surface of the plutonium ball must be passivated to prevent it from spontaneously combusting in the air.

Next comes the actual manufacture of the plutonium bomb.

A plutonium bomb must be of an implosion structure, that is, the spherical plutonium core is precisely compressed to supercriticality through high-energy explosives.

Based on the information, Wang Jiankun designed the first plutonium bomb with a neutron reflection layer, so the critical mass could be reduced to 5 kilograms.

If there were no neutron reflector, the critical mass would have to be at least 10 kilograms.

The implosion structure is actually a great test of design capabilities.

Because the blast wave is arc-shaped, in order to make the blast wave act evenly on all positions of the plutonium ball, the design of the outer layer of explosive is very important.

If they were to start from scratch, they would have to spend a lot of time experimenting to find the best arrangement of the explosives to ensure that the blast wave would reach the plutonium ball in the center evenly and at the same time.

The intelligence community had a lot of information at that time, so Wang Jiankun only spent a few hundred thousand dollars to get the U.S. plutonium bomb design drawings.

Several experimental structures were then built at the Nindiben base (with the central plutonium sphere replaced by other metal spheres).

After the tests were completed, he selected the structure with the best effect and then prepared to start manufacturing the first official plutonium bomb.

(End of this chapter)