Titanium microalloyed steels

Abstract

For many years titanium has been regarded as a relative minor element in microalloyed steels compared with niobium and vanadium. However, over the past decade or so, titanium compounds in microalloyed steels have been recognized as having a wider role than just involved in austenite grain refinement.This is considered in the present review. The background and brief history are followed by sections dealing with the physical state of titanium and compounds of titanium, including borides, carbides, nitrides, oxides and sulphides characterized in MA steels. Many of the investigations on the solubility of these compounds in iron, and the precipitates they form, are considered, which leads to their functions in controlling the mechanical and toughness properties of MA steels.This now often involves the multiple alloying additions of titanium, niobium and vanadium with both carbon and nitrogen, and the morphologies of the various precipitates characterized in MA steels is presented. Titanium has become an important element in the development of line pipe steels, which for the higher grades have moved to bainite/acicular ferrite microstructures. The influence of Ti in the nucleation of acicular ferrite is an active research area, particularly with regard to the use made of titanium compounds in welding of MA steels. Finally, consideration is given to the influence of titanium on hot ductility and how titanium additions behave during continuious casting and thin slab direct charging processes.

Mechanism of Improving Heat-Affected Zone Toughness of Steel Plate with Mg Deoxidation after High-Heat-Input Welding

“…As shown in Table 1, the Ti and N contents in LM were lower and higher than those in A and HM, respectively. According to the results reported by Baker [29], the dense dispersed TiN particles with sizes less than 20 nm was easy to be formed in the Ti microalloyed steel containing low Ti and high N. These nanoscale TiN particles were effective to retard the growth of austenite grain below 1350 °C. Therefore, the austenite grain size for LM at T1~T4 (1200~1350 °C) was much smaller than those for A and HM, as shown in Figure 11.…”

Combined Ab Initio and Experimental Study of Hydrogen Sorption in Dual-Phase Steels

“…The present work is focused on exploring this particular aspect of HE. Titanium and vanadium are two elements which are added for providing grain refinement and solid solution strengthening in micro-alloyed steels [33]. It is speculated that carbide and nitride precipitates of these two elements may be useful in promoting irreversible trapping of hydrogen.…”

A Review of the Effect of a Nanostructured Thin Film Formed by Titanium Carbide and Titanium Oxides Clustered around Carbon in Graphitic Form on Osseointegration

“…Another technique, Transmission Electron Microscope (TEM), is a more complex surface investigation tool which can be coupled with other characterization and manipulation instruments, such as the Selected Area Electron Diffractometer (SAED), for the analysis of the crystalline structure of the sample, the Energy Dispersion Spectrometer (EDS), for chemical analysis, and the ion-beam columns Field Emission Gun (FEG), for micro and nano sample manufacturing [ 37 , 38 , 39 ].…”