As titanium alloys are used in a wider range of applications, attention has also been paid to their quality and durability. A suitable melting method undoubtedly has an important influence on the application of titanium alloys. Five preparation methods for smelting titanium and titanium alloys will be introduced below.
1.Vacuum Consumable Arc Furnace Melting Method
This smelting method is commonly known as the VAR method, and the electrode preparation process is often used. Its significant advantages are low power consumption, high melting speed and good quality reproducibility, and the smelted ingot also has a good crystalline structure and uniform chemical composition. In addition, a single electric arc furnace can produce a variety of ingot types and increase the size of the ingot, which can greatly improve the productivity.
2.Non-consumable Vacuum Arc Furnace Melting Method
This method is referred to as the NC method, and is mainly prepared by using a water-cooled copper electrode. The advantage is that the process of pressing electrodes and welding electrodes can be omitted, the production cost can be reduced, and the recycling of titanium can be realized.
3.Cold Herth Melting Method
In order to make titanium alloys better used in the aerospace field, we must use new methods to solve the defects caused by raw material contamination or abnormal manufacturing process in the smelting process. At this time, the CHM method appeared. According to different smelting heat sources, it can be divided into electron beam smelting method and plasma smelting method. The biggest feature is the separation of melting, refining and solidification processes, which can avoid cross-contamination of impurities.
4.Cold Crucible Melting Method
The method is referred to as the CCM method, and the smelting process is carried out in a metal crucible composed of water-cooled arc-shaped blocks or copper tubes that are non-conductive to each other. The advantages are that the cost of preparation equipment is low and the operation is convenient, but it is still widely used.
5.Electroslag Smelting Method
The ESR method is the use of the collision of charged particles when the current passes through the conductive electroslag as the heat source for smelting. The advantages are high repeatability for making optimal ingots, uniform crystalline structure, high equipment precision and easy operation. The disadvantage is that the contamination of the ingot by the slag cannot be ruled out.
