History of Titanium

Titanium
Titanium, despite what currently is known, is not a metal and is the fourth most abundant structural metal in the earth's crust and is the ninth industrial metal used,
Currently is found in nature as oxide in Ilmenite, black volcanic sands and Ruthile. Metallic titanium is obtained by 3 different processes:
    • transformation into sponge;
      • melting by VAR / EBM to obtain ingots/ slab;
      • then forged/rolled into specific shape and sizes for further processes such as plate; sheets, coils; bars, rings,

metallic titanium is a silvery, ductile metal with density inferior to iron, hardness superior to Al and corrosion resistance nearly as good as platinum.
Titanium is presenting a combination of technological features extremely favourable for a wide range of industrial application:
    • High Mechanical resistance, related to a relatively low density (4,51 Kg /dm3);
      • high corrosion resistance in aggressive environments;;
     • high biocompatibility;
      • high melting temperature (1668°);
     • paramagnetically;
     • low modulus of elasticity, thermal conductivity and coefficient of thermal expansion

Titanium could have 2 different crystalline form:
The first one, namely "Alfa" , corresponding to an hex compact structure, stable at low temperatures, the second one, namely "Beta" has a cubic structure and it is stable at high temperature. In Pure titanium, the alfa phase, is stable at all the temperature up to 882 C, where we assist at the trasformation into the Beta phase. This temperature level (882C) is also known as Beta –Transus and it is constant to the melting point.
Titanium and its alloys are divided in 3 major categories acc. To the predominant assumed by their structure at room temperature. Alfa alloys, Beta alloys e Alfa-Beta alloys.
Last are mostly a compromise between the Alfa and the Beta alloys.
Alpha alloys are non-heat treatable and are generally very weldable. They have low to medium strength, good notch toughness, reasonably good ductility and possess excellent mechanical properties at cryogenic temperatures. The more highly alloyed alpha and near-alpha alloys offer optimum high temperature creep strength and oxidation resistance as well.

Alpha-Beta alloys are heat treatable and most are weldable. Their strength levels are medium to high. Their hot-forming qualities are good, but the high temperature creep strength is not as good as in most alpha alloys.

Beta or near-beta alloys are readily heat treatable, generally weldable, and capable of high strengths and good creep resistance to intermediate temperatures. Excellent formability can be expected of the beta alloys in the solution treated condition. Beta-type alloys have good combinations of properties in sheet, heavy sections, fasteners and spring application