Deformation Temperature Influence Titanium Zirconium Molybdenum Alloy’S Organization Structure

Deformation temperature is one of the important factors affecting the titanium zirconium molybdenum (TZM) alloy organizatiom structure, and changes in the organizational structure of the alloy can also cause changes in their properties. After study the influence of different deformation temperature on TZM alloy found that when the deformation temperature is lower than 1150 ℃, due to the deformation resistance of titanium zirconium molybdenum alloy is large so the cracking becomes serious which can not employ subsequent processing. As the deformation temperature increase, TZM alloy has no cracking phenomenon. Besides, the deformation resistance of TZM alloy decreased and the plasticity increase. When the deformation temperature at range of 1300~1350 ℃, the organizational structure of the alloy is a fibrous elongated grains which are mutually overlapping staggered. Besides, the arrangement between the grains very compact and grain boundaries is straight which has fewer voids. However, if the deformation temperature above 1350 ℃, the grain size of the alloy TZM can cause excessive tissue coarsening. During rolling the alloy will pass through a large thermal deformation, so that the ductility of the alloy to give the corresponding increase, but there is a big internal tissue distortion after deformation. If subsequent processing steps still using higher heating temperature, it is easy to make a crude alloy, reduce performance TZM alloy.

TZM Alloy Organization Structure

After observing TZM alloy SEM image found there uniformly distributed white spherical particles and the shape of the block material. Analysis element content found that the white spherical particles main element is Ti and matrix elements mainly is Mo, Zr and a small amount of Ti, from this we can see that small amount of Ti and Zr form Mo-Ti and Mo-Zr solid solution in TZM alloy with Mo. Bedsides, the solid solution ability of Zr is better than Ti. And this is because the solid solution of TZM alloy is mainly through Mo matrix to dissolve a small amount of Zr, Ti, C and other element making Mo lattice contorted. The size of the solute and solvent atoms greater the difference, the better the reinforcing effect, on one hand, the size difference factor of Zr and Mo is + 14.3. On the other hand, Ti and Mo size difference factor is + 4.4. So the solid solution ability of Zr is better than Ti. Although C and Mo size difference factor is -34.5 which is very large, but due to the C content is low in TZM alloy and most of C will work with Mo, Ti and Zr react generate carbide, at the same time C will be consumed when occurs reduction reaction. Therefore TZM alloy strengthen mainly Mo-Ti and Mo-Zr solid solution strengthening, as well as TiC and ZrC dispersion strengthened which was generated by Zr, Ti, and C. These organization structures not only improve the mechanical properties of the alloy also increases the alloy recrystallization temperature.