"Director Han, is our experiment successful?" Zhao Jingfu asked in a low voice, as if he was afraid that speaking too loudly would affect the results.
Han Fangyun didn't seem to hear it, still carefully watching the data changes on the screen, and then very calmly instructed the engineers to summarize all the data.
In Zhao Jingfu's eyes, this calmness seems to mean another failure. Could it be that the data just now cannot meet the needs of the Blue Whale?
Zhao Jingfu looked at Han Fangyun who was busy in front of him, with great confusion in his heart.
After all the data was compiled, a faint smile finally appeared on Han Fangyun's calm face.
"According to all the data obtained so far, the alloy steel plate we forged has exceeded the F-level strength of 690MPa. Whether it is low-temperature impact toughness or various strengths, it can meet the strength requirements required by the Blue Whale!"
Han Fangyun looked calm with a little pride in his tone. This is the first F-grade ultra-thick and high-strength marine steel in China. This unattractive steel plate means that the independent research and development capabilities of domestic marine steel have reached a new level.
, Hong'an Steel once again broke the monopoly of foreign developed countries on high-tech materials.
"Congratulations to Director Han! Congratulations to Hong'an Steel!" Zhao Jingfu was also very excited at this time.
Although there were only a few dozen days, no heroic incident was seen. Only the scientific research team headed by Han Fangyun, who was unwilling to fail day after day, constantly adjusted the material ratio and optimized the process settings, was able to achieve this goal.
In a short period of time, this steel plate that meets the requirements was presented to everyone.
"It's not easy!" The words Han Fangyun blurted out represented a huge amount of hard work.
When the news of the successful development of the f690 reached Fuhai Group, Zhang Yujie was immediately overjoyed. This meant that the construction of the Blue Whale was imminent. He immediately sent a letter of thanks to Hong'an Steel on behalf of Fuhai Group, and also told him to continue working in Hong'an.
Zhao Jingfu of Steel immediately started conducting welding thermal cycle experiments.
The successful development of f690 is the first step to complete the entire mission. Only through the crack tip opening displacement test in extreme environments is the real goal of the entire material mission.
Among them, the welding thermal cycle experiment is an indispensable part.
Ultra-thick and high-strength steel plates themselves are extremely difficult to weld. It is an extremely stringent test for both the welder's welding skills and the selection of steel plates and welding materials.
In order to complete this task as much as possible, the actual operation is almost impossible. After all, Zhao Jingfu is facing an ultra-thick steel plate with a thickness of more than 100 millimeters. Even if the welding length is only 20 centimeters, it will take a long time.
Calculated in hours.
Hong'an Steel has long thought of this. They have a powerful thermal simulation testing machine that can strictly simulate the thermal cycle generated during the welding process and conduct all-round testing of the performance of the steel plate.
After the 100mm ultra-high-strength marine engineering steel F690 was successfully finalized, Hong'an Iron and Steel immediately carried out primary welding thermal cycle and secondary welding thermal cycle simulation experiments on it, mainly studying the critical reheat coarse-grained zone in the welding heat-affected zone.
Organization and performance characteristics.
This is the main source of influence on the performance changes of the steel plate during the welding process, and it is also an important responsibility that Zhao Jingfu has to shoulder this time.
However, everything will not go as people imagine.
When F690 entered the experimental cabin, an unexpected data disrupted people's joyful mood. Under the action of the secondary welding thermal cycle of the steel plate, a large number of martensite-austenite structures appeared in the critical reheating coarse-grained zone. These structures
Distributed along the original austenite grain boundaries, it seriously destroys the low-temperature toughness of the steel plate, leading to local embrittlement in the heat-affected zone, thereby causing stress damage in the welding area.
The welding completed in this way will directly affect the final stress structure. Once it encounters bad weather or strong force, these welds will cause great hidden dangers to the Blue Whale.
Although this situation is also under everyone's consideration, it is something that no one wants to see happen. After all, if you want to completely solve this problem, you must change the components of f690. Everything must be changed.
Having to start over again would be even worse for Hong'an Steel, which is pressed for time.
"Teacher Han, can we use process adjustment to control the continuous cooling time and provide appropriate tempering process after cooling? Then the ocean can reduce or decompose the massive martensite-austenite structure and make the heat affected zone
The notch toughness is improved!”
Faced with this situation, at the technical analysis meeting, some technicians immediately put forward their own ideas.
Process adjustment can indeed solve the problems faced to the greatest extent, but it cannot eradicate this hidden danger. Once the forging process deviates, it will leave serious hidden dangers. It is impossible for the shipyard to conduct stress analysis on all steel plates. This
Once this kind of steel plate containing hidden dangers enters the Blue Whale, the consequences will be disastrous.
Zhao Jingfu immediately objected, "Teachers, as a resident of Fuhai Group, I hope to put forward some immature opinions!"
Han Fangyun nodded, "Master Zhao, please speak!"
"As for the problems that occurred in the welding thermal cycle experiment of f690, my opinion is to readjust the composition of the alloy steel, and then use auxiliary processes to reduce the decrease in low-temperature toughness as much as possible. Otherwise, once problems occur during the forging process, there will be
Leaving serious hidden dangers is not only irresponsible for the Blue Whale, but also harmful to the quality of Hong'an Steel!"
Han Fangyun nodded silently, and then made the final decision, "Re-adjust the alloy elements of f690!"
This decision means that everything that has been done before will be wiped out in the wind, and all the work will have to be started all over again.
This is the research and development of new materials. Smooth sailing is simply a luxury. They need to experience failures over and over again before they can find a suitable path from countless failures and reach the pinnacle of success.
Although everyone is already familiar with the whole process, they still follow the experimental steps and proceed bit by bit with caution.
Watching these scientific researchers constantly adjusting various data and adding various alloy materials into the molten steel, Zhao Jingfu still felt a little uneasy. However, in order to ensure the health of the Blue Whale and not leave any hidden dangers, he could only eliminate them from the source.
Only by consolidating quality can we become the most powerful blue whale.
Time passed little by little in the flames, and the burning steel plate was once again beaten, forged, quenched, tempered, and withstood the test of ice and fire over and over again.
Not only is the F690 ultra-high-strength marine steel about to be reborn from the ashes, it is also a test for Hong'an Steel's scientific researchers and Zhao Jingfu.