| 摘要 |
<p>PURPOSE: A high-purity tantalum sheet and a manufacturing method thereof are provided to reduce the standard deviation of crystal grains by identifying re-crystallization starting times of the crystal grains. CONSTITUTION: A manufacturing method of a high-purity tantalum sheet is as follows. Tantalum ingot or billet is cold-forged and is re-crystallized by annealing. A recovery annealing process is performed with a less than re-crystallization temperature in order to eliminate residual stress. The casted tantalum ingot or billet is finally cold-rolled and is re-crystallized by annealing. The recovery annealing is performed for 20 to 40 minutes.</p> |
