Eyes closed.
Then slowly opening it, Richard saw that he was already in outer space, surrounded by many bright stars.
As soon as he thought, the stars were approaching quickly, and his body fell towards one of the planets.
There is an ocean on the planet, an island on the ocean, a forest on the island, and a magnificent conjoined library in the forest. Not long after, he had entered the library and sat in a purple hall in the library.
In the hall were numerous mahogany bookshelves over three meters high, filled with books. A long-necked turtle statue took a heavy book from the bookshelf and placed it in front of him.
Reaching out to open it, he saw what was on it—the technology for making atomic bombs①.
Manufacturing an atomic bomb is both difficult and easy.
When the first atomic bomb was manufactured, the most powerful country on earth used all the technology it had, hundreds of thousands of people served it, and a large number of the world's top scientists participated. It took several years to succeed.
Before its success, the atomic bomb was undoubtedly the most advanced creation in the world.
But as soon as the atomic bomb was manufactured, it began to fall from the clouds. The top technology became an outdated theoretical basis. The difficulty changed from extremely high to very low, and almost anyone was able to repeat it. This is mainly because when the first atomic bomb was manufactured, no one knew whether it would be successful. A lot of energy and material resources were invested in trial and error and verification to study whether this road could work.
Once this road is determined to be passable, all the obstacles on the road will no longer be obstacles. At most, they will be some pebbles. The unattainable technology becomes a craft that ordinary technicians can handle. , the difficulty plummeted from the previously unimaginable to nothing more than that.
This is the power of science.
The initial breakthrough was as difficult as hell, but after the breakthrough, it became a smooth road. What was once created by a group of top scientists with great difficulty can be replicated later by just finding a few physics-educated students in the university, using completely open knowledge, and provided they have enough raw materials.
This is not a metaphor, this is a fact.
The country that first produced the atomic bomb on earth actually tested it in this way, and then knew that the atomic bomb technology cannot be completely blocked. The only thing that can be blocked is the raw materials at most.
Technology is like this, you don’t need to know what it is, you just need to know whether it can be realized.
Therefore, making an atomic bomb is both difficult and easy. What is difficult is the beginning, but what is easy is everything after the beginning.
According to the principle, the key to the manufacture of atomic bombs lies in the issue of critical mass.
Atomic bombs are different from conventional bombs. Conventional bombs do not have critical mass problems, and the number of explosives is not limited. You can load as much as you want. But atomic bombs cannot do that. Once the nuclear material in the atomic bomb reaches a critical mass, or even exceeds the critical mass, it will be in a dangerous state where a nuclear explosion may occur at any time.
In order to prevent accidents or accidents such as self-explosion of nuclear weapons before use, when the atomic bomb is stored, it must ensure that the nuclear material loaded inside is below the critical mass, that is, in a sub-critical mass state.
When it is actually put into use, the nuclear material loaded inside must reach a situation that exceeds the critical mass in a very short time, that is, a supercritical state. Only in this way can we ensure that during the fission chain reaction, the number of free neutrons multiplies up to the standard, and nuclear raw materials can be used efficiently to release the expected devastating destructive power.
An atomic bomb can only be considered a qualified atomic bomb if it solves the "crossing" problem of critical mass.
To solve this problem, we must know that the critical mass is related to the geometric shape and physical density of the nuclear material. A piece of supercritical nuclear material becomes subcritical if it is divided into multiple pieces, or if its volume is increased and its density is reduced, it will become subcritical.
What the atomic bomb specifically does is to divide the nuclear materials in the bomb body into several pieces. When used, the several pieces of nuclear materials can be accumulated together instantly through the internal device to reach supercriticality, and then a neutron source is provided to activate a continuous nuclear chain reaction. Produce a nuclear explosion.
The most important word among them is fast.
It has to be fast, it has to be very fast.
Because the nuclear explosion occurs in a very short time, it is necessary to ensure that the detonation is extremely fast, otherwise the bomb body will be exploded in advance before it is completely detonated, wasting the remaining precious nuclear materials.
Generally speaking, detonation must be completed within one ten thousandth of a second. When different nuclear materials are squeezed together, the time difference must be shortened to one millionth of a second, so that there will be no big difference in the explosion of the atomic bomb. .
If this can be done, then the atomic bomb will complete its mission in three tremors and release a mushroom cloud of destruction.
Tremor is a term coined when the first atomic bomb was created. A tremor lasts only one billionth of a second, and light can barely travel three meters in this period of time.
Three tremors, light traveled nine meters in a vacuum, and an atomic bomb completed everything from beginning to end.
It's so short.
It's extremely short, so it's extremely powerful.
…
Manufacturing a qualified internal device for an atomic bomb involves a variety of knowledge such as detonation physics, fluid mechanics, shock wave dynamics, high temperature and high pressure condensed matter physics, etc.
Generally, this internal device is composed of five parts: a detonation control system, high-energy explosives, a reflective layer, nuclear components containing nuclear materials, and a neutron source.
The detonation control system is responsible for detonating the high-energy explosive layer, and then using the impact of the explosion to push and squeeze the reflective layer and nuclear components, allowing the nuclear materials to reach a supercritical state. The neutron source then provides neutrons for "ignition", allowing the nuclear material to begin a continuous nuclear chain reaction, successfully triggering a nuclear explosion.
In a conventional sense, internal devices are divided into two major types: gun type and implosion type.
The internal device of the gun type is relatively simple, generally requiring only two pieces of sub-critical mass nuclear material.
The entire device looks like a cylinder, or an iron pipe. In the middle of the iron pipe, there is a neutron source. At both ends of the iron pipe, a hemispherical nuclear material will be placed - with the plane facing inward and the sphere facing outward.
The outer spherical surface of the hemispherical nuclear material is wrapped with a reflective layer that reflects neutrons (used to reflect neutrons and improve the efficiency of sustained nuclear chain reactions), and then high-speed explosives, boosters, detonators, and Detonator.
Once the device is activated, under the power of the explosive explosion, the two hemispherical nuclear materials will move toward the center, collide in a very short time, and be squeezed into an oblate spherical shape, reaching a supercritical state. At this time, the neutron source will release a large number of neutrons, causing the nuclear material to produce a continuous nuclear chain reaction, triggering a nuclear explosion.
The advantage of this kind of device is that it has relatively low technical content and is easy to manufacture. The disadvantage is that the utilization rate of nuclear raw materials is also low. Because when reaching the supercritical state, the nuclear material is not overly squeezed and has a normal density. In other words, the atoms are not dense enough, and it is like suddenly pushing two hundred-person teams of students together on the playground. Although the standard is met, it is only the standard, and the sustained nuclear chain reaction is not fast enough.
On Earth, the first atomic bomb used in actual combat by a major country was such a gun-type device. Because the technology is simple, it was used directly without even conducting nuclear tests. The effect is very impressive. The nuclear raw material is loaded up to 64 kilograms, and the utilization rate is only 1.2% - yes, 1.2%. The remaining 98.8% is wasted, and the power equivalent of TNT is only 15,000 tons.
Note ①: All the technical knowledge of atomic bomb manufacturing involved in this article comes from the official website of the China Institute of Engineering Physics, Wikipedia and other online public information, as well as publicly published books such as "Jingtian Nuclear Network".