Ukraine Snake Island Flag - Buy it Here!

Weapons of Mass Destruction (WMD)


Second-generation Nuclear Weapons

In order to further improve the capability of nuclear deterrence, the issue of miniaturization of nuclear weapons must be solved. This requires a breakthrough in engineering design, test technology and other aspects. At the same time, the difficulty of processing increased sharply, and the requirements for processing accuracy and proficiency were much higher than those of earlier nuclear bombs. A group of technically active workers in the forefront also paid tribute to ordinary people's hard work.

After the atomic bombs and hydrogen bombs were acquired, China's nuclear weapons program is technically built around miniaturization. The second-generation nuclear weapons, which were bundled with the second-generation strategic missiles, began in the mid-1970s. Jeffrey Lewis wrote in "Nuclear-weapons design and testing" that "As part of the transition to boosted weapons, the US developed external neutron generators using pulse-neutron tubes. China did not develop a pulse-neutron tube until the mid-to late 1970s, a sign of its relatively slow progress toward modern thermonuclear weapons." The pulsed neutron generator may use a D-T reaction to produce 14 MeV neutrons, which are emitted virtually isotropically from the target. One variant is a system of generating pulsed neutrons wherein deuteron ions are accelerated to bombard a tritium target for generating neutrons by the reaction of T(dn). An improved pulsed neutron generator can produce large amount of neutrons with extraordinary short time of build up and attenuation.

Pulsed neutron generators have been used in the petroleum industry since the late 1950s. Ordinarily, the earth formations that promise the best potential oil production are very porous. Determining the porosity and fluid content of subsurface earth formations are critical elements in maximizing the efficiency of oil, gas, and water (“formation fluids”) exploration. To that end, a variety of techniques have been developed. One of the well known techniques involves irradiating the subsurface earth formations with high-energy neutrons and monitoring the resulting energy spectra. A Minitron™ typically includes a ceramic tube containing tritium and deuterium at low pressure. This device creates neutrons at an energy of 14 MeV by accelerating deuterium ions into a tritium target. Such a system is often found in a pulsed neutron generator (PNG).

Measurements of this sort are accomplished with a borehole logging tool that comprises two neutron detectors spaced at diiferent distances from a pulsed neutron generator. The thermal neutron decay time of the short-spaced detector identifies that portion of the time-dependent pop ulation that is most indicative of the formation porosity. Both detectors then register the portion of the neutron distribution so identified to produce two signals from which a ratio is computed that is related to the porosity of the formation.

A series of tests were carried out from 1982 to 1988 to test the correctness of the design principles and to break through the key technologies. In October 1984, after the successful test of the netorn bomb, nuclear miniaturization design tests began. The definition of miniaturization here is strictly speaking miniaturization relative to the first generation of nuclear warheads. In the scientific classification, with the first generation, second generation, the third generation of the division, the first generation of atomic bombs, hydrogen bombs second generation, third generation are devics such as neutron bombs. Primary miniaturization includes miniaturization of explosive parts.

The Central Committee of the Special Commission proposed that the development direction of the second generation of nuclear weapons to be small, mobile, effective, safe and reliable. The Commission of Science, Technology, Industry and Sports Commission and the Second Machinery Department issued the task of developing the second generation of nuclear weapons to the Nineth Intitute. To achieve such a goal, it is crucial to miniaturize and improve the power of hydrogen bomb nuclear devices, not only adopting new design ideas and new structures in the physical design of weapons, but also in engineering design, materials science, testing technology and processing technology Breakthrough in all aspects. Researchers divide the task of theoretical design into 14 key issues and 34 technical difficulties.

In the development of new explosives components, researchers put forward many scenarios, from which five program organizations were selected for exploration and comparison, known as the "Five Golden Flowers". Finally the main attack on a program to effectively solve the small explosive parts began. The explosives had been reduced to just a few tenths of the original weight and volume. The manufacture of nuclear material parts was very difficult to process and the material of the nuclear parts was very expensive.

For Hydrogen bomb miniaturization, the key is the primary miniaturization, using the principle of assisting the explosion (the primary is not a pure fission bomb). The so-called "bursting explosion" means adding a small amount of fusion material in the center of the fission device initiates the fusion reaction with low fission power, releasing the high energy neutrons so as to improve the utilization efficiency of the primary fissile material. This is an important measure of primary miniaturization. The aid to the primary explosion is divided into "gas burst" and "solid aid burst". Boosting with solid material refers to lithium-6, and the gas boosting material refers to a fusion weapon in the form of deuterium and tritium gas. China initially used the primary of the solid auxiliary blast in the DF-5 nuclear warhead and the primary gas-assisted explosion in the second generation of nuclear weapons.

Since the initiation of aids (especially gas aids) involves a complex series of physical processes, a large number of simulation calculations were required and verified by nuclear tests to gradually find out the law. China's preliminary miniaturized nuclear test passed the three tests of October 5, 1982, October 6, 1983 and October 16, 1984. Finally, the principle of gas assisting explosions was finally broken out and the Nineth Institute won the 1987 State Scientific and Technological Progress Grand Prize.

Sub-miniaturization mainly solves the tradeoff between power and weight dimensions. The secondary consists of a combination of fissile and fusion materials. Due to the vast difference in densities of fissile material (uranium or plutonium) and fusion material (deuterated lithium), the same volume of uranium or plutonium is about 24 times heavier than deuterated lithium. The full energy of fusion fuel is about 3 times that of fissile fuel of the same weight. To reduce the volume requires the use of fissile material (correspondingly increased the power of fission share); to reduce the weight requires less fissile material (and correspondingly increased the power of fusion shares). Therefore, the secondary miniaturization design, according to the warhead size, weight requirements were traded off as far as possible to meet the increased power requirements.

The mid-1980s was the crucial moment for the development of the second generation nuclear weapons in China. The principle of primary miniaturization had been broken through. The technical approach of secondary miniaturization had also been clarified. China's nuclear weapons were only a step away from the world's advanced level. The nuclear weapons design of the United States and the Soviet Union were already close to the theoretical limit.

For limiting the political needs of China's development, they may end underground nuclear tests at any time and propose a comprehensive test ban. If China did not do the full yield test before the nuclear test ban, it would not get needed data, and it would lose its opportunity and fall short of power, causing irreparable huge losses. Yu Min, Hu Renyu and Hu Sidhi recalled in an article published in 1996: "The severe situation has caused Deng Jiaxian to become extremely anxious." Despite his serious illness, he personally organized research discussions, drafted reports to the Central Committee, and expressed his opinions and suggestions. He put forward the strategic proposals for seizing the opportunity and speeding up the pace of development and the major goals that need to be concentratedly tackled and set out in concrete detail the specific ways and measures to achieve these goals. This is a work that embodies the work of Jiaxian and his colleagues Patriotic enthusiasm, but also very objective and scientific proposal.

On April 2, 1986, the proposal signed by Deng Jiaxian and Yu Min was completed and submitted to the Central Government. The Central Committee approved their report very soon. July 29 the same year, Deng Jia first died. Subsequently, under the organization of the State Commission of Science, Technology and Industry Commission of National Defense , the concrete plan for speeding up the development of nuclear weapons was formulated. With a high sense of urgency and sense of responsibility, the majority of scientific and technological personnel were united and determined and are determined to break the path of "climbing with their own characteristics".

The second generation of nuclear weapons should be truly weaponized to ensure that they are safe, reliable and effective, meet the requirements of the armed forces and facilitate their use, and further improve their configuration and miniaturization. In order to adapt to the tapered shape of a miniature warhead, the primary was stuffed into the nose cone and the Nineth Institute also developed a gas-assisted primary combustion of a non-spherical configuration, culminating in a nuclear test on September 25, 1992.

The United States and the Soviet Union developed various types of nuclear weapons and developed dozens of models to form a large arsenal of nuclear weapons and meet various needs of strategy and tactics. China's research and development workers, focusing on advanced design concepts and advanced science and technology, focused their efforts on developing a limited number of key models - "effectively smashing the nuclear monopoly and nuclear blackmail in the major countries".




NEWSLETTER
Join the GlobalSecurity.org mailing list



 
Page last modified: 04-02-2018 17:30:55 ZULU