A loud and dull sound resounded in the rough machining workshop. Under the continuous high-intensity impact of the hammer head, the shape of the electroslag steel ingot weighing 1.5 tons changed dramatically. It gradually became slender from short and thick, and was in the process of recrystallization.
The interior of the steel ingot above the temperature becomes denser than before forging, and the physical properties continue to improve.
Unfortunately, due to the small kinetic energy of the one-ton air hammer, the material properties of the electroslag steel ingot cannot be improved much. If there is a hydraulic press with a pressure of 10,000 tons, the physical properties of this electroslag steel ingot will be qualitatively improved.
leap.
Professor Zhuang constantly issued various instructions and directed the forging team workers to carry out forging processing and strive for perfection.
Yu Hua did nothing. He ate dried meat and admired the birth of the world's first electroslag steel gun barrel from a third-party perspective.
As time passed, for two hours, the electroslag steel ingot with excellent comprehensive properties was repeatedly heated and forged, and finally reached the rough processing size standard of the gun barrel blank, turning into a solid gun with a diameter of approximately 130 mm × 4900 mm.
Pipe blank.
This solid gun barrel blank can obtain two heavy artillery barrels that meet the design specifications at one time.
"I really don't know which giant's shoulders you stand on."
Professor Zhuang looked at the rough-machined solid barrel blank on the anvil, glanced sideways at Yu Hua, and couldn't help but sigh again. In all his years of living, he had never seen steel with such performance.
By observing the reaction performance during rough machining of electroslag steel ingots, Professor Zhuang has clearly realized that electroslag steel has incredible comprehensive mechanical properties, with strength, hardness, and toughness far exceeding any steel he has known, and various mechanical properties.
The parameter combination reaches an extremely balanced state.
Steel with extremely balanced various mechanical properties!
In the field of steel and metallurgy, this is simply an impossible goal.
Steel has its own characteristics, advantages and disadvantages. High carbon steel has high hardness and strength, but low toughness. Medium carbon steel has medium hardness and strength, but has high toughness. Low carbon steel has low hardness and strength, high toughness and ductility, and high strength is impossible.
, steel with high hardness and high toughness.
However, now it has really happened.
The title of epoch-making steel is no exaggeration.
"Professor, it's time to proceed to the next step." Yu Hua smiled and pointed to the solid gun barrel blank in front of him.
"Prepare for quenching." Professor Zhuang understood, took a deep breath, turned around, stared at the solid barrel blank, and began to arrange the quenching process.
The quenching process is the most important and critical step in the metal heat treatment process. It is indispensable. The heated metal is quickly immersed in the quenching medium to cool it down quickly, so as to obtain as much martensitic metallographic structure as possible, thereby significantly improving the hardness of the metal.
and strength, this is the strongest material amplification magic mastered by humans.
According to the needs and quenching medium, quenching is usually divided into water quenching, oil quenching, salt water quenching, etc. For the solid gun barrel blank made of electroslag steel material, the most stable and efficient oil quenching is used for this quenching.
Oil quenching has unique advantages over water quenching. The advantages are stable and gentle physical properties, excellent basic cooling coefficient and oxidation resistance. The workpiece is not easy to crack and deform during quenching. The disadvantages are high cost and easy generation of pollution and fire.
Apart from being expensive, there are no major drawbacks. This is oil quenching.
The advantages of water quenching are low cost, the highest basic cooling coefficient, and the workpiece can obtain higher hardness during quenching. However, because the cooling rate is too high, cracking may easily occur when processing the workpiece.
Heavy artillery barrels do not emphasize a single high hardness, but pursue comprehensive and balanced mechanical properties to meet their own needs. There is no need to use water quenching for hardness and bear the risk of cracking.
Soon, the special heating furnace was ignited and heated up. The solid barrel blank was operated by a dedicated person and placed into the special heating furnace by crane. The overall temperature of the blank was heated to the range of 850℃±20℃ for about 20 minutes, so that the internal
The temperature should be as uniform as possible.
After the heating process is completed, the critical link comes.
The four workers took out the solid gun barrel blank as quickly as possible, then hooked it up to the 4-point long-distance hook of the truck, and lifted the 4,900 mm long gun barrel blank to the sky above the exclusive cooling pool.
quick!
All steps must be done quickly to avoid overheating of the blank when it comes out of the furnace.
The exclusive cooling pool is square, 5 meters long and 3 meters deep. The two meters inside are filled with clear and fresh mineral oil, totaling 50 cubic meters. This is a cooling pool specially built for processing heavy artillery barrels. Fifty cubic meters
Mineral oil is worth thousands of dollars, so it is not cheap.
As the vehicle descends, the high-temperature solid barrel blank contacts the surface of mineral oil, and the cold oil meets the hot parts. In an instant, a flame rises into the sky, and the contact area burns violently. As the gun barrel blank is quickly immersed in the cooling pool, its own heat flows toward
It spreads rapidly around and cools down stably and quickly based on the theoretical cooling coefficient of mineral oil medium.
The heat waves are rolling, the temperature is rising, and the cooling pool is as busy as a frying pan.
Professor Zhuang stood in a safe area, observing the conditions in the cooling pool. When the second hand of the watch passed forty-five seconds, he immediately made a gesture to indicate that the vehicle would be raised.
"Buzz!" The sound of the running motor came out, the steel rope contracted, the white high-temperature mist drifted away, and the gun barrel blank immersed in mineral oil slowly rose up, revealing the surface of the pool and entering everyone's sight.
The barrel blank is straight and dark, with an uneven surface and dense forging marks. Obviously, after the quenching heat treatment process, the actual mechanical properties of the entire barrel blank have been improved again.
"It's so beautiful." In the distance, Yu Hua admired the gun barrel blank as an audience, carefully observing every part, with a look of intoxication in his eyes.
Beautiful things always make people feel comfortable.
Just as winemakers are intoxicated by the taste of making top-quality wine, military industry experts are equally obsessed with the process of creating top-notch military equipment.
Regarding the world's first electroslag steel gun barrel, Yu Hua can only say - perfect.
"Classmate Yu, is this the cannon pipe we are going to build?" At this moment, a familiar accent from Hu Province suddenly came from beside him, and a very familiar middle-aged figure came into view, with a smile on his face and a touch of easy-going.
The temperament, the milled-soled cloth shoes, the clean shirt that has been washed many times, a pair of eyes that shine like stars, and the cigarette in his hand.
Secretary Li and the two security guards accompanying him smiled and nodded, standing on both sides to protect their safety.
"Sir, why are you here?" Yu Hua was a little surprised when he saw the visitor, and quickly said hello respectfully.
"Of course I have to come and see the big event. This is the first cannon in our base. Originally, the boss and others wanted to come, but I didn't let it. It would be bad if it caused pressure to you." The middle-aged man smiled jokingly,
Then he asked with a hint of curiosity: "What are you doing now?"
"Now it is part of the heat treatment process. The first quenching has been completed, and then the first tempering is carried out. There are three quenching times in total, so that the mechanical properties of the gun barrel blank can reach the best state." Yu Hua introduced like a treasure trove: "
After the heat treatment process is completed, it enters the finishing stage. The blank is sawed into two parts to obtain two barrel blanks. After subsequent processes such as turning, boring, rifling, chrome plating, etc., the finished barrel is finally obtained.
.”
"Okay, okay, we can finally produce our own cannons." Hearing this, the middle-aged man looked around, smiled and nodded at Secretary Li and the guards: "Classmate Yu, I heard before that we have actually been able to produce cannons for a long time.
Cannon barrels are just manufactured barrels, are they of poor quality?”