Further, they also state that there are as many as 3,500 different grades of steel and each grade offers environmental, chemical and physical properties unique to that grade of steel. Steel has undergone significant evolution through time and around 75% of all the types of modern-day steel were developed in the past 20 years. It is interesting to note that had the Eiffel Tower (constructed in 1887) been constructed in today’s times, it would require only one-third of the steel used back then.https://www.hengrui-topsteel.c....om/stainless-steel-c