Tecnologia di preparazione di lingotti di leghe di titanio a basso costo

Titanium and titanium alloy materials have excellent comprehensive properties such as low density, high specific strength, good toughness, non-magnetic properties, and good corrosion resistance, which have led to their widespread application in important fields such as aviation, aerospace, naval vessels, nuclear power, as well as in civilian markets such as petroleum, metallurgy, chemical industry, electric power, and biomedicine. However, their high cost has limited their further promotion and popularization for civilian use. Recently, some new titanium alloy ingot preparation technologies have emerged, which can effectively address this issue. The main ones are:

1. Development of low-cost titanium alloys
By alloy design, adding cheap alloy elements (such as Fe) to replace expensive alloy elements (such as V), low-cost titanium alloys are developed to expand the application of titanium alloys. This method is highly feasible, using low-cost alloy elements to achieve the goal of reducing costs.
The low-cost high-strength titanium alloy Ti-1.5Al-6.8Mo-4.5Fe, developed by Timet in the United States, utilizes Fe as an alloying element, and its performance is comparable to that of Ti-1023, while its cost is only 78% of that of Ti-6Al-4V. The automotive titanium alloy Ti-6Al-1.7Fe-0.1Si outperforms Ti-6Al-4V, and its cost can be reduced by 15% to 20%.

2. Incorporate return scrap preparation technology
During the production process of titanium alloys, a certain amount of scrap material is generated during melting, forging, hot rolling, cold rolling, and tube extrusion. After cleaning and sorting by grade, the ingots and scraps can be reused by bundling them into electrodes and melting them in vacuum arc furnaces (VAR), electron beam cold hearth furnaces (EBCHM), or plasma arc cold hearth furnaces (PACHM). The maximum recovery rate of scrap material can reach 100%.
The price of titanium scrap is only 20% to 30% of the price of raw material sponge titanium. By adding returned scrap, not only does it significantly reduce the production cost of some grades of titanium alloys, meeting the needs of the market and customers, but it also provides an effective way for the secondary utilization of scrap.

3. New smelting method
Currently, the methods used internationally for producing large-sized high-quality titanium alloy billets include the application of new electron beam cold hearth furnace and plasma cold hearth furnace melting technologies, as well as direct rolling technology after single cold hearth furnace melting.
The new melting method can partially replace vacuum consumable arc furnace melting, achieving short-process manufacturing technology from the process flow. It eliminates processes such as electrode pressing with hydraulic presses and vacuum welding in traditional vacuum consumable arc furnace melting, while also allowing for significant recovery of residual materials. The application of cold hearth furnace melting technology not only improves the quality of titanium and titanium alloy ingots but also reduces costs. Especially when using a single cold hearth furnace technology to melt titanium alloys directly into flat ingots, processing costs can be saved by 10% to 20%. Preparation technology for low-cost titanium alloy ingots