my scientific age

Chapter 392 Quenching!

Impact is the art of forging steel!

Forging steel is the charm of steelmaking!

A loud and dull sound echoed throughout the rough processing workshop. Under the continuous high-intensity impact of the hammer head, the shape of the electroslag steel ingot weighing 1.5 tons changed dramatically, from short and thick to slender. The interior of the steel ingot above the recrystallization temperature became denser than before forging, and its physical properties continued 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 were a hydraulic press with a pressure of tens of thousands of tons, the physical properties of this electroslag steel ingot would achieve a qualitative leap.

Professor Zhuang constantly issued various instructions, directing the forging group workers to carry out forging processes, striving for perfection.

Yu Hua did nothing but eat some dried meat and appreciate from a third-party perspective the process of the birth of the world's first electric slag steel gun barrel.

As time went by, after two hours, the electroslag steel ingot with excellent comprehensive performance finally reached the rough processing size standard of the gun barrel blank through repeated heating and forging, and became a solid gun barrel blank with a diameter of about 130 mm × 4900 mm.

This solid gun barrel blank can produce two heavy artillery barrels that meet the design specifications at one time.

“I really don’t know whose shoulders you are standing on.”

Professor Zhuang looked at the solid gun barrel blank that had been roughly processed on the anvil, turned his head to glance at Yu Hua, and couldn't help but sigh again. He had lived for so many years and had never seen steel with such performance.

By observing the reaction performance of electroslag steel ingots during the rough processing, Professor Zhuang has clearly realized that electroslag steel has incredible comprehensive mechanical properties. Its strength, hardness and toughness far exceed any steel he has known, and the combination of various mechanical parameters has reached an extremely balanced state.

Steel with extremely balanced mechanical properties!
In the field of steel 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 high toughness. Low carbon steel has low hardness and strength, but high toughness and ductility. It is impossible to have steel with high strength, high hardness and high toughness.

However, it has now really appeared.

It is no exaggeration to call it epoch-making steel.

"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 quickly cool it down and obtain as much martensitic metallographic structure as possible, thereby significantly improving the hardness and strength of the metal. This is the most powerful material amplification magic mastered by humans.

Quenching is usually divided into water quenching, oil quenching, brine quenching, etc. according to the needs and quenching media. For solid gun barrel blanks made of electroslag steel, 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 mild physical properties, excellent basic cooling coefficient and anti-oxidation performance, and the workpiece is not easy to crack and deform during quenching. The disadvantages are high cost and easy to cause pollution and fire.

Apart from being expensive, there is no major disadvantage, and that is oil quenching.

The advantages of water quenching are low cost and the highest basic cooling coefficient. The workpiece can obtain a higher hardness during quenching, but because the cooling rate is too high, cracking is prone to occur when processing the workpiece.

The barrel of a heavy artillery does not emphasize a single high hardness, but rather pursues comprehensive and balanced mechanical properties to meet its own needs. There is no need to use water quenching for the sake of hardness and bear the risk of cracking.

Soon, the special heating furnace was ignited and heated up. The solid gun barrel blank was operated by a special person and placed into the special heating furnace by a crane. The overall temperature of the blank was heated to the range of 850℃±20℃ and maintained for about twenty minutes to make the internal temperature as uniform as possible.

After completing the heating phase, the key phase comes.

Four workers took out the solid gun barrel blank as quickly as possible, and then hung it on the 4-point long-distance hook of the crane, and lifted the 4900 mm long gun barrel blank to the top of the exclusive cooling pool.

fast!
All steps must be completed quickly to avoid excessive temperature drop of the blank when it comes out of the furnace.

The exclusive cooling pool is square, 5 meters long, wide and 3 meters deep. The two-meter line inside is filled with clear and fresh mineral oil, a total of cubic meters. This is a cooling pool specially built for processing heavy artillery barrels. cubic meters of mineral oil is worth thousands of oceans, which is very expensive.

As the crane descends, the high-temperature solid barrel blank contacts the surface of the mineral oil. When the cold oil meets the hot part, a flame rises into the air in an instant, and the contact area burns violently. As the barrel blank quickly immerses in the cooling pool, its own heat quickly spreads to the surroundings, and the temperature drops steadily and quickly based on the theoretical cooling coefficient of the mineral oil medium.

The heat waves rolled in, the temperature rose, and the cooling pool was as lively as an frying pan.

Professor Zhuang stood in a safe area, observing the conditions in the cooling pool. He waited until the second hand on his watch reached forty-five seconds, then gestured to signal the vehicle to rise.

"Buzz!" The sound of the crane's motor was heard, the steel rope contracted, white high-temperature mist dissipated, and the gun barrel blank immersed in mineral oil slowly rose, revealing the surface of the pool and coming into everyone's sight.

The barrel blank is straight, black all over, and the surface is not smooth, covered with dense forging marks. Obviously, after the quenching heat treatment process, the actual mechanical properties of the entire barrel blank have been further improved.

"It's so beautiful." Far away, Yu Hua was admiring the gun barrel blank as a spectator, carefully observing every part, with an intoxicated look in his eyes.

Beautiful things always make people feel comfortable.

Just as winemakers revel in the taste of making top-quality wines, military experts are also fascinated by the process of creating top-notch military equipment.

Regarding the world's first electroslag steel gun barrel, Yu Hua can only say - perfect.

"Student Yu, is this the cannon barrel we want to make?" At this moment, a familiar Hubei accent suddenly came from beside me, and an extremely familiar middle-aged figure came into view, with a smile on his face, revealing a casual temperament, cloth shoes with thousand-layer soles, a clean top that had been washed many times, a pair of eyes that sparkled like stars, and a cigarette in his hand.

Secretary Li and two guards who were accompanying them smiled and nodded, standing on both sides to protect the safety of the two.

"Sir, why are you here?" Yu Hua was a little surprised to see the visitor and greeted him respectfully.

"Of course we have to come and see this big event. This is the first cannon in our base. The boss and his men wanted to come over, but I didn't let them. It would be bad if it put pressure on you." The middle-aged man smiled jokingly, and then asked with a hint of curiosity: "What are you doing now?"

"Now it is the heat treatment process. The first quenching has been completed, and the first tempering will be carried out next. A total of three quenchings and three times will make the mechanical properties of the barrel blank reach the best state." Yu Hua introduced like a treasure: "After the heat treatment process is completed, it will enter the finishing stage. The blank is sawed in half to obtain two barrel blanks. After the subsequent turning, boring, rifling, chrome plating and other processes, the finished barrel is finally obtained."

"Great, great, we can finally produce cannons ourselves." The middle-aged man heard this, looked around, and nodded to Secretary Li and the guards with a smile: "Student Yu, I heard before that we can actually make cannon barrels a long time ago, but the quality of the barrels we made is not good?"

(End of this chapter)