After iron, aluminium and copper, titanium is the fourth most abundant metallic element in the earth's crust. Moreover, titanium alloys have a series of excellent properties and are therefore increasingly widely used. Titanium alloys can be divided into high temperature titanium alloys, structural titanium alloys and functional titanium alloys according to their application background. In addition to casting, titanium alloys can also be forged, superplasticised and welded.
Titanium is a very active metal, in the liquid state and oxygen, nitrogen, hydrogen and carbon reaction is quite fast, so titanium alloy melting must be in a high vacuum or inert gas (Ar or Ne) protection. The crucibles for melting are water-cooled copper crucibles, and there are three main types of specific melting processes:
Non-self-consuming electrode arc melting Alloy melting is carried out under vacuum or inert gas protection. The process mainly prepares electrodes for self-consumption electrode melting.
Vacuum self-consumption electrode arc melting uses an electrode made of titanium or titanium alloy as the cathode and a water-cooled copper crucible as the anode. The melted electrode enters the crucible in the form of liquid droplets, forming a molten pool. The surface of the molten pool is heated by the electric arc and is always in a liquid state. The bottom and the surrounding area in contact with the crucible are subjected to forced cooling, resulting in bottom-up crystallisation. The liquid metal in the molten pool solidifies and becomes a titanium ingot.
Vacuum self-consumption electrode condensation shell guard melting this furnace is in the vacuum self-consumption electrode arc developed on the basis of it is a kind of melting and centrifugal pouring into the casting of shaped parts of the furnace type. Its most important feature is the presence of a solid thin shell of titanium alloy between the water-cooled copper crucible and the molten metal. This layer of the same material acts as a lining for the crucible, which is used to form a molten pool to store the titanium liquid, avoiding contamination of the crucible by the titanium alloy liquid. After casting, a layer of congealed shell left in the increase loss can be used as the crucible lining.
In recent years, with the development of science and technology and production needs, successive research and development of melting titanium alloy and other active metal new methods and equipment, mainly electron beam furnace, plasma furnace, vacuum induction furnace, and so on, and get a certain degree of application. However, from the comparison of power consumption, melting speed, cost and other technical and economic indicators, self-consumption electrode arc furnace (including condensing shell furnace) melting is still the most economical and applicable melting method.
At present, the quality control before furnace adopts NB-800 series photoelectric direct-reading spectrometer, which can quickly and conveniently detect the content of each element in titanium alloy, and it greatly facilitates the on-site quality control of furnace workers!
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Casting and forming of titanium alloys
After iron, aluminium and copper, titanium is the fourth most abundant metallic element in the earth's crust. Moreover, titanium alloys have a series of excellent properties and are therefore increasingly widely used. Titanium alloys can be divided into high temperature titanium alloys, structural titanium alloys and functional titanium alloys according to their application background. In addition to casting, titanium alloys can also be forged, superplasticised and welded.
Titanium is a very active metal, in the liquid state and oxygen, nitrogen, hydrogen and carbon reaction is quite fast, so titanium alloy melting must be in a high vacuum or inert gas (Ar or Ne) protection. The crucibles for melting are water-cooled copper crucibles, and there are three main types of specific melting processes:
Non-self-consuming electrode arc melting Alloy melting is carried out under vacuum or inert gas protection. The process mainly prepares electrodes for self-consumption electrode melting.
Vacuum self-consumption electrode arc melting uses an electrode made of titanium or titanium alloy as the cathode and a water-cooled copper crucible as the anode. The melted electrode enters the crucible in the form of liquid droplets, forming a molten pool. The surface of the molten pool is heated by the electric arc and is always in a liquid state. The bottom and the surrounding area in contact with the crucible are subjected to forced cooling, resulting in bottom-up crystallisation. The liquid metal in the molten pool solidifies and becomes a titanium ingot.
Vacuum self-consumption electrode condensation shell guard melting this furnace is in the vacuum self-consumption electrode arc developed on the basis of it is a kind of melting and centrifugal pouring into the casting of shaped parts of the furnace type. Its most important feature is the presence of a solid thin shell of titanium alloy between the water-cooled copper crucible and the molten metal. This layer of the same material acts as a lining for the crucible, which is used to form a molten pool to store the titanium liquid, avoiding contamination of the crucible by the titanium alloy liquid. After casting, a layer of congealed shell left in the increase loss can be used as the crucible lining.
In recent years, with the development of science and technology and production needs, successive research and development of melting titanium alloy and other active metal new methods and equipment, mainly electron beam furnace, plasma furnace, vacuum induction furnace, and so on, and get a certain degree of application. However, from the comparison of power consumption, melting speed, cost and other technical and economic indicators, self-consumption electrode arc furnace (including condensing shell furnace) melting is still the most economical and applicable melting method.
At present, the quality control before furnace adopts NB-800 series photoelectric direct-reading spectrometer, which can quickly and conveniently detect the content of each element in titanium alloy, and it greatly facilitates the on-site quality control of furnace workers!
