◎ Science and Technology Daily intern reporter Sun Yu
In the old photo, three researchers are manually developing explosive components under minimally simple protective conditions.
Researchers manually operate the development of explosive components. Image source: CNNC 221 Bureau
Liu Zhendong, who was the head of the explosive molding process technology team of the second room and the second group of the Ninth Institute in Beijing, did not appear in this old photo, but the development of explosives was exactly what he was engaged in.
The 91-year-old repeatedly told reporters during the interview: "I am honored to participate in the manufacture of the first atomic bomb! ”
Liu Zhendong was at home. Photo by Sun Yu, intern reporter of Science and Technology Daily
Explosive components are an important part of the manufacture of atomic bombs.
High-energy explosives are touted as the "trigger" for detonating the atomic bomb, and the detonation test is the first step to the success of the atomic bomb.
In the late 1950s, sino-Soviet relations deteriorated, and the Soviet Union withdrew aid experts and took most of the materials with them. China is determined to rely on itself and develop a "gas bomb" at an early date.
In the midst of the crisis, the Ninth Institute of Engineering Physics in Beijing (now the China Academy of Engineering Physics) set up a second room responsible for detonation physics, and appointed Chen Nengkuan, an engineering physicist who graduated from Yale University in the United States and later won the "Two Bombs and One Star" Meritorious Medal, as the director of the room.
The picture shows a photo of Chen Nengkuan before his death. Image source: Communist Party members' network
At the foot of the ancient Great Wall of Hebei Province, the curtain on the development of explosive components was officially opened.
The first shot of the detonation test was fired
The place where the curtain opens has a code name called "Site Seventeen". It refers to China's first nuclear weapons detonation test site located between Jundu Mountain and Guanting Reservoir in Huailai County, Hebei Province, at the foot of the Ancient Great Wall. This land gave birth to the prototype of China's first atomic bomb.
Today, it's lush, with trees lined with former moving sand dunes and several trails looming.
In 2005, Liu Zhendong returned to the 17th construction site. Courtesy of Liu Zhendong
Go back in time to 1960.
The Seventeenth construction site is located at the outlet of the wind, and in the winter and spring, the strong air flow from the south of Saiwai pours into this area, rolling up the wind and sand.
A large number of researchers and workers came to this land.
In the winter testing ground, not everyone has a bed. Wooden planks were set up into a bunk, covered with grass mats, and dozens of people slept on them one by one. The room is not equipped with a heating pipe, and you can only burn your own coal stove for heating.
The cold wind and harsh conditions still could not resist their fiery energy.
Without advanced instruments and equipment, everyone engaged in "soil method", thinking of ideas, finding ways, using aluminum pots and aluminum spoons as containers for casting explosives, and welding double barrels with aluminum to melt explosives.
Workers in the second room process explosives with rudimentary tools such as aluminum barrels and aluminum shovels. Image source: An Oral History of Chinese Science in the 20th Century, courtesy of Liu Zhendong
Liu Zhendong told the Science and Technology Daily reporter, "On April 28, 1960, on the eve of May Day, we officially launched the first shot of the detonation test, and everyone's morale was very high. ”
Combine theory and experiment to find the best ratio
After the first shot was fired, the development of explosive components for atomic bombs was carried out more intensively.
"Site 17 is firing all year round, and at its most it explodes 22 times a day." Liu Zhendong said that in order to improve the detonation effect, frequent experiments must be made to find the best proportion of mixed explosives.
Making explosives and then exploding sounds like something very simple. But in reality, it involves incredibly complex processes.
At that time, explosives were mainly composed of TNT and Black Sogin. The explosives need to be disassembled, the ingredients checked and weighed on a balance. Through the high-burst group, low-burst group to issue materials, check the mold, measure the temperature of the drying box and other steps, in order to enter the pouring, nursing, stirring, nursing, re-stirring of explosives production links. Finally, there are processes such as the normalization of explosives, the opening of molds at the mouth of the mouth, sampling and cutting, and physical and chemical analysis.
The actual operation behind each process is delicate work.
The process of melting the explosives requires workers to stir with wooden sticks. At that time, there was also a joke called "the tip under the stick".
"Just like a doctor performing surgery and a chef stir-frying, when stirring explosives, you must concentrate on stirring them, and you must maintain a certain temperature, otherwise it will affect the quality of the explosive components and even cause the explosives to fail to pour." Liu Zhendong said.
Workers at site 17 poured atomic bomb explosive parts. Image source: An Oral History of Chinese Science in the 20th Century, courtesy of Liu Zhendong
Liu Zhendong's team is also responsible for pouring and forming explosives.
"Pouring explosives is generally small and can be formed in one day, while large ones take three days," he said. The cannon is finished in a few microseconds, and the production can take three days, and the operation time difference is too much. Therefore, our group is working overtime, there is no change of rest, can only shift each other, in order to match the speed of the artillery group. ”
Through repeated exploration experiments, technical workers and scientific researchers learned the theories taught by Chen Nengkuan, Wang Ganchang and others, supported each other with the detonation test data, jointly found the best proportion of explosives development, and broke through the various technical difficulties in the development of explosive components.
Return to the No. 17 construction site and take a group photo in front of the monument of the detonation test site (Chen Nengkuan on the third from the right and Liu Zhendong in the second from the right). Courtesy of Liu Zhendong
Eating willow leaves also requires the production of explosive parts as soon as possible
During the days of the 17th construction site, during the three-year difficult period of the national economy, the main and sideline food were not supplied, and everyone was hungry every day. My stomach was so hungry that I could only flush some soy sauce and paste to fill my hunger.
In order to fight hunger, everyone also held a "spiritual meal". You say you've ever eaten something, and I describe the deliciousness I've eaten. Talk about it for days, as if hunger is no longer so unbearable.
Liu Zhendong told reporters with a smile: "I am the leader of the group, and I want to take the lead in doing demonstrations, so I work harder than others." Some people call me 'Desperate Samurai'. But unfortunately, my appetite is also bigger than others, and in difficult times, the willow leaves on the side of the road have not yet grown, and they have become my plate. ”
Eat willow leaves in the spring, eat wild vegetables in the summer and autumn, and go to the orchard in the autumn to pick up sand fruits that fall on the ground.
When stirring explosives, the human mouth is bitter. When stirring, the gas volatilizes outwards, wearing a mask is not very effective, but it will be more serious if it is not worn.
"Workers are very able to endure hardships, and they are not enough protective gloves and protective clothing, so they still work." Liu Zhendong said emotionally: "They have worked hard and complained about the most dangerous work, and they have indeed dedicated their lives to the country and to the cause of nuclear weapons." ”
It is under such a very simple condition that researchers and workers constantly record the relevant data of the production of each explosive part, hold meetings to discuss, analyze problems and defects, find solutions, and finally improve the production quality and detonation effect of explosive parts step by step.
"This is the result of collective labor." Liu Zhendong said.
In 1963, the ninth institute and the second room of the ninth institute, which successfully developed the data related to the molding of atomic bomb explosives, were moved to the 221 factory in Qinghai Province. There, the explosive components of our first atomic bomb were assembled.
Yang Du, a technician engaged in the development of new explosives in the 218 research room of the second branch of the second factory, told reporters: "We are going to the place where the motherland needs it. The motherland needs it, and we are here. ”
Yang Du, 83, was interviewed by reporters. Photo by Sun Yu, intern reporter of Science and Technology Daily
Yellow sand can't blow away the imprint of history. For everyone involved in the construction of "two bombs and one satellite", that is their most glorious cause.
He has been buried in anonymity for thirty years, and he has served the country for life without remorse.
Source: Science and Technology Daily