The industrial production of titanium and titanium alloys, whether remelted consumable electrodes, forging blanks, or deformed castings, is mostly obtained by vacuum arc melting of consumable electrodes. With the development and progress of modern technology, titanium and titanium alloy smelting, including vacuum consumable electrode arc smelting, has developed some new advanced technologies. Representative technologies in recent years are as follows:
1. Preparation method of electrode for vacuum self-consumption melting of titanium alloy with high melting point metal directly added
In vacuum since the electricity arc smelting with titanium alloy electrode, on the basis of conventional preparation by the direct suppression of certain grooves of the electrode block and is suitable for the high melting point metal rod electrode block groove shape of welding electrode method, by choosing appropriate vacuum since the electricity arc melting process, can achieve melting the matching calculation requirement, composition of even no segregation of high quality ingot.
2, titanium and titanium alloy vacuum self-consumption melting process after the interruption of the arc process
Titanium and titanium alloy vacuum self-consumption melting process after the interruption of the arc process, including the following steps: when the interruption of the arc, the melting current quickly raised to 75-80% of the normal melting current, maintain the melting current at this time; When the edge of the molten pool reaches the wall of the crucible, keep it for 2-3min, and then quickly raise the smelting current to the normal smelting current. The technology advantage, make the total arc starting time shortened significantly, reduce the cooling of the ingot after the volume shrinkage and the crucible wall between the gap and avoid the formation of ingot solidification cooling internal shrinkage: when melting current reaches 75 to 80% of normal melting current, keep the melting current for a period of time, so that we can more accurately control electrode and has solidified melt velocity of molten pool, Avoid instantaneous large amount of molten liquid flowing into the gap between the ingot and the crucible wall, or cause cold separation defects.
3. Smelting and recovery method of pure titanium bulk waste
In the smelting and recovery method of pure titanium bulk waste, the electron beam cold bed furnace with six electron guns is used to load the raw materials of selected components into the feeder of the electron beam cold bed furnace for melting, and then the obtained ingot is cooled and baked, and the finished product can be obtained. In this method, TA1 recycled material is directly used for melting, which avoids crushing of scrap electrode block and welding of electrode. For single ingot smelting, a single device can melt 9 bars per day with a total weight of about 6.5 tons. For double ingot smelting, a single device can melt 18 bars per day with a total weight of about 13 tons, which greatly improves the recovery efficiency and speed
4. Electron beam cold bed melting recovery method for titanium and titanium alloy scrap
The electron beam cold bed melting recovery method of titanium and titanium alloy scrap is as follows: according to the melted titanium and titanium alloy composition, the pure titanium scrap, or one or two of the pure titanium scrap and titanium alloy scrap mixed with titanium sponge and pure alloy added elements and/or intermediate alloy, The addition amount of pure titanium and titanium alloy scrap in the mixture is 10%~90% according to the mass percentage; The electrode block is then pressed into an electrode block, and the electrode block is subjected to a single electron beam cold bed melting in an electron beam cold bed melting furnace to obtain titanium or titanium alloy ingots. This method can produce qualified pure titanium ingot from up to 100% pure titanium scrap, or up to 90% titanium and titanium alloy scrap, and produce qualified titanium alloy ingot. Only the electron beam cold bed is needed for primary melting, not secondary or tertiary melting.
5. Smelting method of clean titanium and titanium alloy ingot
Pure titanium and titanium alloy ingot melting method, the method is: according to take titanium sponge or take pure alloy elements added, intermediate alloy and titanium sponge and titanium sponge or pure alloy mixture to add elements, intermediate alloy and titanium sponge pressed into the electrode block, will be pressed into the electrode piece of welding electrode, using electron beam cooling bed furnace electrode on a cooling bed of the electron beam melting, To obtain clean, homogeneous chemical composition of titanium or titanium alloy ingots; The vacuum degree of electron beam cold bed melting is less than 6×10-2Pa, the melting speed is 70~150kg/h, the melting power is 100~ 300kW; Pure alloy addition elements and intermediate alloys are 0%~20% of the total weight of titanium alloy ingot. The chemical composition of titanium and titanium alloy ingot is uniform, and the macro structure of ingot is better than that of vacuum arc melting ingot without high melting point inclusions such as TiN and WC.
6. Smelting method of titanium alloy containing high melting point alloying elements
Industrial preparation of titanium alloy ingot containing high melting point alloying elements. By SELECTING THE RAW MATERIAL OF THE ALLOY, USING THE electrode block SPECIALLY assembled, using the conventional vacuum consumable arc melting technology, adjusting the current and voltage of three times melting, the titanium alloy ingot with uniform chemical composition and no inclusion and containing high melting point alloy elements was prepared. High melting point metal distributed evenly in the consumable electrode, consumable electrode convenient preparation, low cost, reasonable smelting as current, voltage parameters, on the basis of traditional craft route, using a low-cost pure metal plate according to the specific consumable electrode spellers way, instead of adding the middle of the high cost of alloy and pure metal to join other titanium alloy, Titanium alloy ingot with uniform composition and high melting point alloy elements was obtained by using vacuum arc melting furnace for many times, which is suitable for industrial application.
7. Preparation of TC4 titanium alloy ingot by electron beam cold bed furnace melting
The method of preparing TC4 titanium alloy ingot by electron beam cold bed furnace melting is as follows: the titanium sponge and aluminum-bean are mixed evenly and pressed into electrode block, then the electrode is welded into a vacuum consumable arc furnace, and the Ti-AI intermediate alloy is obtained by one smelting. The Ti-Al intermediate alloy is broken into Ti-Al intermediate alloy particles. The titanium sponge, Al-V intermediate alloy and Ti-Al intermediate alloy particles were mixed evenly and pressed into electrode blocks, which were spliced into electrodes and placed in an electron beam cold bed furnace, and TC4 titanium alloy ingot was obtained by primary melting. Among the Ti - Al alloy instead of aluminum beans, reduced the Al elements volatilize quantity, improve the utilization rate of raw materials and the use of electron beam cooling bed furnace efficiency, the use of an electron beam cooling bed furnace smelting in titanium processing cost and improve production efficiency with the advantages of stronger, and can improve the cleanliness of the titanium alloy ingot casting, access to quality of ingot casting.