What is the Stainless Steel 2.0 Era?

Stainless Steel 2.0 Era, the time span is about 50 years in the second half of the 20th century. The main achievements of this stage include: breakthroughs in stainless steel refining technology, innovations in stainless steel welding processing technology, and expansion of stainless steel application areas. The outstanding feature of this period is that stainless steel gradually changed from expensive special alloys (knife steel and aviation steel, etc.) to commonly used manufacturing raw materials.

In the stainless steel 1.0 era, the commonly used production process includes three steps: smelting, decarburization and alloying. Since the key alloying element chromium of stainless steel has the characteristic of "absorbing" carbon and oxygen, it is difficult to decarburize, resulting in very high costs for low-carbon ferrochrome used in the "alloying" stage. Therefore, low-cost decarburization of stainless steel smelting process and smelting of ultra-low carbon stainless steel at a lower cost have become the focus of steel mills and metallurgical technicians during this period.

Bill (William) A. Krivsky has made great contributions to the breakthrough of stainless steel smelting process technology, which has not only reduced smelting costs but also improved product quality. He received his Ph.D. from MIT in 1954 and joined the Metal Research Laboratory of Union Carbide. When studying how to control the high temperature of thermal reactions in the smelting furnace, Bill A. Krivsky tried to dilute oxygen with argon and found that the carbon content of stainless steel was significantly reduced. Through further experiments, he believed that he could develop a refining process for low-cost production of ultra-low carbon stainless steel. On June 27, 1956, Bill A. Krivsky submitted a patent application for the AOD (Argon Oxygen Decarburization) smelting system, but it was not approved until May 24, 1966. Fortunately, he used more than ten years to perfect the AOD process. During this period, Linde Air Products Company, a subsidiary of Union Carbide, also achieved low-cost commercial production of argon and oxygen using the air liquefaction process. Joslyn, a small stainless steel producer in Indiana, signed a contract with Union Carbide in 1960 to conduct experimental production of the AOD smelting process. After many failures, the first furnace of ultra-low carbon stainless steel produced by the AOD process was successfully produced on October 24, 1967. The refining time was only 58 minutes, and the carbon content dropped to an incredible 0.008%. The decarburization of the AOD process means that the stainless steel industry can produce high-quality stainless steel in a low-cost way. By 1982, about two-thirds of the world's stainless steel production used the AOD process. By 1990, global stainless steel production exceeded 10 million tons. By 2000, more than 100 AOD furnaces had been installed worldwide.

The breakthrough in low-cost stainless steel refining technology naturally brought about the popularization of stainless steel applications. During this period, Budd Manufacturing Company continued to expand the application of stainless steel in various types of transportation and once became the largest stainless steel user in the United States.

In the processing and manufacturing of stainless steel, welding is the most important technology. A reasonable welding process can avoid the deterioration of the strength and corrosion resistance of stainless steel around the weld. Earl James Wilson Ragsdale, a resistance welding expert at Budd Manufacturing Company, perfectly solved the problem of welding nickel-containing stainless steel in a cold working state. Earl J. W. Ragsdale is a retired Army colonel and a talented mechanical engineer who graduated from the Massachusetts Institute of Technology. After retiring, he became a resistance welding expert at Budd Manufacturing Company. On January 16, 1934, Earl J.W. Ragsdale obtained a patent for resistance spot welding, entitled "Method and Product of Electric Welding", which is the most important patent in the history of Budd Manufacturing Company. Earl J.W. Ragsdale further developed automated welding equipment, which almost eliminated the possibility of bad welding, with stable quality, and the spot welding speed was extremely fast, lasting only 0.008 seconds, which would not affect the strength and corrosion resistance of the stainless steel substrate. Ragsdale also solved the problem of weld quality control. Welding also eliminated the use of rivets, greatly improving the firmness, sealing and aesthetics of the product. Due to the correct selection of nickel-containing stainless steel and the successful solution of welding problems, Budd Manufacturing Company quickly expanded its business to cars, trains, airplanes, subways, urban rail cars, airport shuttles, etc.

The significant reduction in stainless steel production costs and the improvement of processing technologies such as welding have promoted the continuous expansion of stainless steel applications. More and more buildings use stainless steel curtain walls and stainless steel bars, some famous outdoor sculptures are made of stainless steel, and every household uses household appliances and kitchen utensils made of stainless steel.