| Abstract: | Titanium an up-to-date material for the construction of chemical apparatus – A contribution to the knowledge of damages In recent years titanium has been used increasingly for chemical plant owing to its high resistance to corrosion and favourable price/weight ratio. Titanium is outstandingly resistant to a number of critical media, such as aqueous chloride solutions, chromic acid, sulphuric acid, moist chlorine gas and solutions of substances in nitric acid. Titanium is entirely non-resistant to media containing fluorine, to dry chlorine gas, to red fuming nitric acid, to hydrochloric acid and to methanolic hydrochloric acid solutions; in the last-mentioned solutions titanium that is subjected to sufficiently severe tensile stresses suffers stress corrosion cracking. Titanium owes its high resistance to corrosion to a passivating oxide layer which separate the really very base metal from the hostile environment. Damage to the oxide layer, as often caused by flowing media, for example, causes the titanium to be attacked within a short while. In this article we discuss, as a contribution to the knowledge of how damage arises, numerous typical examples of damage which, through ignorance of the limitations of titanium, or through the emergence of unforeseeable operating conditions, has occurred over the years in several factories of the company to which the authors belong. |
