What are the stages of the titanium ingot casting process?

Titanium ingot casting process is generally divided into three stages, first step is batching, second step is bundled electrode, and third step is casting.

1. Batching

Titanium alloys determine the proportion of alloy elements according to the following principles:

A: The range of allowable fluctuations of alloy elements and impurities, and the optimum composition range required for the optimum properties of the alloy;

B: Smelting method and smelting times;

C：Burning rate and evaporation rate of alloy elements in vacuum white smelting process;

D: The addition of alloying elements and their physical properties.

Under normal circumstances, for the burning rate of large, volatile elements, the proportion of ingredients close to the upper limit or above the limit, however, for not volatile, the loss of elements in accordance with the requirements of the limits of ingredients.

2. Pressing of electrode blocks

The requirements of consumable smelting on electrodes are mainly:

A: Enough strength;

B: Enough electrical conductivity;

C: The distribution of alloying elements in the electrode is reasonable;

D: Not damp or polluting.

There are two kinds of preparation methods for single electrode, pressing and extruding, and pressing method is more common.

3. From the beginning of the transmission, smelting until all the melting furnace finished, this process is called furnace melting stage. At the beginning of the smelting process, the specific resistance of new burden is larger, the electrode is in direct contact with the furnace charge and heats the charge by the resistance of the furnace. At this point the input current is small but relatively stable. During this period the resistance to heat is predominant. But this time is not long, when the electrode charge form three "below the melting crucible melting pool", and "the crucible" electrode of molten pool arc heat generated between the heating charge of the weld pool expands gradually, until the formation of a communication between the three electrode "pool". During the transition from the "pool" to "big pot", not because of the molten pool was partially melted charge reduction, the resistivity decreases, so the resistance of furnace heat gradually reduced; while the electrode and the "crucible pool" arc between the ratio increased gradually. After about half an hour from the melting process, the arc heat is predominant.