"The order was as follows: by March 1989, 945 steel with the standard performance must be developed for the construction of the 052 lead ship. ”

Chief Engineer Qi told the necessary background information in concise language, the smaller the number of words, the bigger the matter.

"Wow, 052 ship!"

The engineers were excited, all of them military experts.

"We only have two years of research and development time, and the time is tight and the task is heavy, everyone has a task on their shoulders, and everyone immediately takes action to complete the task in a race against time. Chief Engineer Qi was not so optimistic, he was not excited, and even a little dignified.

After the confession of Chief Engineer Qi, the 52 researchers were divided into 9 groups and devoted themselves to the research work.

There are five members in the Ye Guoguo Group, he is the team leader, and the other four team members are Engineer Zhang Tongqiao, Engineer Liang Minfang, Engineer Liu Yahui, and Assistant Engineer Zhao Qingshan.

"We come from different research laboratories, and in the 945 steel project team, there is no administrative level, only scientific cooperation. I'm not a director, I'm a steel engineer like you. ”

Ye Guoguo first set the tone, and said: "903 steel is a nickel-free chromium yield strength greater than 450N/mm^2 grade of surface ship steel, the navy is in large demand, initially in Anshan Iron and Steel production, and later Jianggang joined the 903 steel team, in 73 years to produce 903 steel. I started to follow up the production and improvement of 903 steel in 74 years, and I still know a lot about 903 steel. ”

"The times have changed, the needs have changed, even if the military representatives do not come to Jianggang, we also know that the historical mission of 903 steel has been completed, and it can retire with honor. So what is the core of the alloy design of 945 steel, which is more advanced than 903 steel, is the issue we want to discuss now, please speak enthusiastically. Ye Guoguo took out a pack of Hongtashan and sent a cigarette to Zhang Tongqiao.

Zhang Tongqiao is a smoker that Ye Guoguo is familiar with, he took the cigarette with a smile, and before lighting the cigarette, he said: "903 steel is made from a steel-making open hearth furnace and rolled out by the third old, if there is no new equipment and new technology, 945 steel will not be much stronger than 903 steel." Fortunately, we have a 1.7 meter rolling mill system, and 1.7 meters has reached the approved design capacity, and we are very promising to make 945 steel with a grade of performance improvement within two years. ”

"There is nothing to do with eight words, Zhang Tongqiao, don't be blindly optimistic. Liang Minfang frowned, and she said, "You gay men, can you stop smoking? Can you bear with it?"

Zhang Tongqiao put the cigarette on his ear: "Okay, okay, bear with it, bear with it." ”

"When I think about big issues, I can't help but smoke. Respect lesbians, don't smoke, don't smoke. Ye Guoguo put away his cigarette and said he was sorry.

Zhao Qingshan said: "Following the topic of Zhang Gong, the one-meter-seven rolling mill system provides strong support for 945 steel, and in the hot rolling process of HSLA, the carbides of chromium and molybdenum do not produce obvious strengthening effects, but only play a certain strengthening effect through solid solution in other precipitated phases." The whole significance of microalloying is not limited to grain refinement, one of the most important functions is to achieve precipitation enhancement ......"

"What I said is more theoretical, and the source of information is the relevant information of 903 steel and 903A steel stored in the Institute of Steel Research. According to reference sources, the first ship of the DDG-51 has been launched, but the information of Bath Steel is simply not available. So our 052 and our 945 steel, rely on ourselves, and we can only rely on ourselves. ”

"Xiao Zhao is looking at the world, DDG-51 is the latest destroyer of the US imperialists, and we don't dare to ask for its information!" Zhang Tongqiao slapped his thighs and said: "The head of the Navy requires us to provide qualified 945 steel before March 89, combined with the actions of the US imperialists, there is a lot of article in this!"

"High-performance warships are an important part of naval construction, and the process of modernizing the construction of the people's navy depends on the research and development of new types of warship materials.

"Two military experts, are you far away?" Liang Minfang pulled the topic back to engineering design, she said: "Xiao Zhao is right, as far as the general toughening mechanism is concerned, grain refinement is the only way to improve both the yield strength and fracture toughness of steel." Xiao Zhao just analyzed chromium and molybdenum, and I will talk about manganese, nickel, silicon, and copper, which directly contribute to the strengthening of steel, and the amount is only between 10~15MPa, but it is often used to change the phase transformation kinetics and microstructure of steel. Of course, the desirability of nickel is also to promote lateral slip and potentially improve low-temperature impact toughness......"

The crowd had a heated discussion for three consecutive days.

Although a confidentiality agreement has been signed, it is not a closed management, everyone has finished the day's work, it is time to go home and go home, and it is time to rest.

In terms of alloy design, Ye Guoguo finally made a summary: "Thank you for your cooperation and active communication, I will make a summary, 440MPa grade steel grade can not achieve the required mechanical properties in terms of its F-P structure, only the introduction of bainite can achieve the expected effect, but in non-quenched and tempered alloy steel, it is usually seen in granular bainite, and the toughness is not ideal." The general direction of 945 steel alloy design has been determined, and there are many problems that need to be overcome. ”

Each team member was assigned a specific task, and the battlefield was transferred to the laboratory and trial production workshop.

The first thing to determine is the chemical composition of 945 steel, and the most important thing is the alloying elements.

Zhao Qingshan mentioned chromium and molybdenum in the discussion, so okay, Xiao Zhao, your task is chromium and molybdenum.

Although the carbides of chromium and molybdenum do not have an obvious strengthening effect, these two elements still have an important role and cannot be replaced in 945 steel, and the content needs to be determined.

The results of the studies that have been reported so far show that Cr is the most effective element in delaying the bainite transition.

Zhao Qingshan selected the test steel in the supply state of 16mm, and the experiment began.

The smelting and rolling of the test steel shall be arranged in the trial production workshop of the Iron and Steel Research Institute.

The trial production workshop of the Steel Research Institute has 0.5 tons of electric arc furnace, 150 kg intermediate frequency furnace, 180 kg high frequency furnace, 10 kg vacuum furnace, ∅ 500 rolling mill, ∅ 360 hot rolling mill and other equipment.

Although there is no 50-ton reblowing converter and continuous casting equipment, it can also meet the test requirements of Zhao Qingshan.

A furnace of test steel is not only for Zhao Qingshan, the rest of the team members and other team members have problems reflected in each furnace of test steel, to verify their theoretical ideas and engineering design, to find key data and the key to victory.

Time flies quickly, and it's the end of February in a blink of an eye.

The furnace 945 test steel is being smelted in the furnace, the furnace temperature is gradually increasing, and the samples at each temperature are taken out one after another for a bunch of engineers to study and analyze.