Magnetic titanium and titanium alloy precision casting foundry

Improve pouring liquid metal mold in pressure but also by the electromagnetic force to the liquid metal to achieve, this approach is the magnetic casting. Its basic principle isto cast off the magnetic pump is installed in the liquid metal to pass, in order to establish the magnetic field; at the same time, DC are also introduced into this segment has established the field of liquid metal flow, in alternating magnetic and electric fields, the formation of the electromagnetic force direction and the liquid metal flow the same, in order to improve the liquid metal mold filling pressure. This method can be used to make the metal in the mould cavity flow than static casting by direct velocity metal indenters the runner to increase 2~2.5 times. In the use of such casting method has several points should be paid attention to:

1 liquid metal is poured into the runner must maintain the continuity of liquid metal flow, intermediate cannot appear to flow. So we must pay great attention to the spruesize design and electromagnetic pump and current value choice.

The 2 magnetic pump should be placed in the water outside the level, thereby reducing the consumption of metal casting system.

3 liquid metal mold filling should be carried out in magnetic pump pressure 0.01~0.05MPa, so as to ensure the liquid metal to flow speed requirements in the cavity, avoiding intermediate drying. In the mold is filled, we should raise the magnetic pump pressure to 0.12~0.3MPa, to improve the feeding ability of castings, castings appear to prevent hole.

4 in the design of gating system should make in this part of the runner of magnetic pump within the liquid metal in the last solidification, which must establish the following:casting solidification sequence -- other gating system -- magnetic pump ingate,because before the pressure can only be built magnetic pump and liquid metal in themold to maintain the liquid metal magnetic the pump runner in the no solidification.Cast researchers to adopt this method in investment casting ceramic shell casting thealloy compressor blade body length up to 260mm. When pouring the liquid metal fillingthe cavity of the blades is carried out in the electromagnetic pump pressure 0.035~0.04MPa condition. This ensures that the liquid metal to 1.4~1.7m/s in the cavity flow rate, thus ensuring the blade surface of cast no cold shut flow mark,forming good. The centrifugal casting this blade is the blade body twist, the presence of cold insulation and loose leaf surface of casting, qualified rate and low metalutilization coefficient.

What is the metal titanium powder and titanium sponge powder what is the difference

Method the sponge metal titanium produced metal thermal reduction. % purity (quality) is generally 99.1 ~ 99.7. Impurity elements% (quality) a total of 0.3 ~ 0.9, impurity elements oxygen% (mass) of 0.06 ~ 0.20, hardness (HB) ranged from 100 to 157, according to the different purity of WHTiO to MHTi4 five grades. As the main raw material for the preparation of industrial Titanium alloy valve. Sponge titanium production is the basic link of titanium industry, it is titanium, titanium powder and other raw materials of titanium component. The ilmenite becomes four titanium chloride, then put in a sealed stainless steel tank, filled with argon, making them react with the magnesium metal, get "titanium sponge". The porous, "sponge titanium" is not used directly, also must put them in an electric furnace melting into a liquid, in order to cast titanium ingot. Sponge titanium production is the basic link of titanium industry, it is titanium, titanium powder and other raw materials of titanium component. The ilmenite becomes four titanium chloride, then put in a sealed stainless steel tank, filled with argon, making them react with the magnesium metal, get "titanium sponge". The porous, "sponge titanium" is not used directly, also must put them in an electric furnace melting into a liquid, in order to cast titanium ingot.

Why study the reaction of titanium plates with steam

Tests carried out in a vacuum apparatus with a quartz microbalance in the spring . Reading accuracy is 4 × 10 - sample surface g / cm . Titanium Welded Tubes Mercury manometer measuring system connected to the reaction chamber using the pressure.
    Titanium iodide as a sample . Breaking titanium strip cold rolled to a rod 0.7 mm thick . Then cut the strip size is 9 × 25 mm sample . In order to eventually remove surface dirt , before the test sample with a finely sandpaper and etched in 7% HNO3 solution in HF.
    The tube is filled with distilled water and vacuum means connected to the plug and the device as a source of water vapor . In order to remove the dissolved water gasification will remain for some time in the water under the stars . Samples were heated to a predetermined temperature in a vacuum after the tube with water and the system is turned on, and set up the equilibrium vapor pressure corresponds to the temperature in the system . When the system is full , the system is filled with water and cut off the tube , Titanium heat exchangers and then tested in a closed volume.
    Under 800,850,900 and 950 ℃ and 14 mm Hg vapor pressure tested titanium plate and steam reaction.
    Kinetics of these tests indicate that , in the beginning stage of the reaction , the reaction with water vapor titanium plates subject to the parabolic law . After the reaction started after a certain period of time becomes linear parabolic law rule.
    In order to identify the effect of pressure on the reaction rate , once at 4 mm Hg pressure two experiments.
    Titanium plate during the reaction and steam , and any of metals, and also the reaction gas , is composed by a number of successive stages , in which the main are: 1 ) the gas molecules collide with the metal , 2 ) gas molecules adsorbed on the metal surface 3 ) the dissociation of the gas molecules , 4 ) through the surface of the film agent diffusion reaction product , 5 ) chemical reaction.
    The reaction rate depends on the speed of the pro stage . It was found that the reaction pressure is reduced because the rate of 5 /6 and steam manganese Titanium heat exchangers remains unchanged , so it should be acknowledged that the reaction speed depends on the diffusion of the reagents through the surface of the membrane , since it is the only one speed stage and the gas pressure independent.

Impact on performance titanium heat treatment cycle

The phase transition in titanium stress is small, with a simple heat treatment, it is difficult to change the original casting organizations, especially the grain boundary organization.
To refine casting titanium organization, people were cycling in the heat treatment. Volume effect of the use of the accumulation phase, resulting in
And increased stress, prompting aerospace investment castings recrystallization, resulting in multilateral and grain refinement sheet of tissue. 

     Experimental results show that the alloy has Ti6A14v thick widmanstatten, the P-phase region through a ten cyclic heat treatment (980 a
500 ℃), enables thin sheet first roughening, and broken off, so that the structure refinement. Then a continuous grain boundary is not
Change, and even some coarsening. titanium precision casting  If the cyclic heat treatment (980 a 500 ℃, 10 times the water-cooled ten 900 ℃, 2h air-cooled) before pre-
P first heated to a broken fire zone (1010 ℃, water quenching), become fully martensite after cycle heating and cooling, a grain boundary 

Disappeared or broken off, the degree of refinement and organizational uniformity will increase its alloys have significantly improved fatigue performance.

titanium sponge powder Titanium applications in medicine

Titanium applications in industrial manufacture increasingly broad ax , and the application in the civilian medical devices are also beginning to show common state. In medical applications , titanium can be used as a bone for transplantation into humans .
    According to the British " Daily Times " titanium sponge powder on November 4 daily to London from fog caused numerous traffic accidents , one of which is two cars rear-end , where a young couple on the spot on the car knocked dizzy and hurt women head has a lot of bleeding.
    With the help of enthusiastic people live under the hurt was taken to hospital immediately . Hospital emergency room staff immediately conduct the inspection, found that women significantly hurt the head hematoma , must undergo an operation and has more than 30 ml . During the surgery doctors found that the patient's head a little piece of bone , titanium sponge powder usually the bones to go back to fill in half a year later , then a piece of bone less how to do it now ? According to experts, doctors at the hospital explained: wound directly above the scalp , scalp has grown well, you can use a titanium plate to replace bone Jieshang Qu , because the long head swear on the scalp , so it will not affect hair growth , and will not affect beautiful lady , the surgery is very successful.

titanium sponge powder Titanium applications in medicine

Titanium applications in industrial manufacture increasingly broad ax , and the application in the civilian medical devices are also beginning to show common state. In medical applications , titanium can be used as a bone for transplantation into humans .
    According to the British " Daily Times " titanium sponge powder on November 4 daily to London from fog caused numerous traffic accidents , one of which is two cars rear-end , where a young couple on the spot on the car knocked dizzy and hurt women head has a lot of bleeding.
    With the help of enthusiastic people live under the hurt was taken to hospital immediately . Hospital emergency room staff immediately conduct the inspection, found that women significantly hurt the head hematoma , must undergo an operation and has more than 30 ml . During the surgery doctors found that the patient's head a little piece of bone , titanium sponge powder usually the bones to go back to fill in half a year later , then a piece of bone less how to do it now ? According to experts, doctors at the hospital explained: wound directly above the scalp , scalp has grown well, you can use a titanium plate to replace bone Jieshang Qu , because the long head swear on the scalp , so it will not affect hair growth , and will not affect beautiful lady , the surgery is very successful.

Casting titanium and titanium alloy

Traditional lost wax casting technology in the production of titanium prosthesis is not easy to succeed, because ti is very lively, high temperature easily and the atmosphere or package elements buried in feeding response. Therefore, titanium casting requires a special heat source model, special materials and prevent the titanium surface pollution equipment. Special dental dissolved atmosphere titanium casting: vacuum and inert gas protection law. Inert gas is argon and helium. Fusionmethods are: high frequency induction method and arc melting method. Casting methods: differential pressure casting, pressure casting and centrifugal casting method. Medical | education network collected differential pressure casting method is the metal melting chamber and the chamber pressure difference casting titanium and titanium alloy cast into the mold cavity. Pressure casting method is the protection ofinert gas at low pressure of melting titanium material, when the melted liquid titanium and titanium alloy to cast crossing, to be higher on the surface of titanium and titanium alloy liquid pressure, the liquid titanium cast into the mold cavity. In addition, the use of cast titanium metal crucible, crucible and high density graphite crucible. Metal crucible for copper crucible, and the use of arc melting method. Titanium casting forembedding material titanium casting. Also note that in the titanium casting process:casting thickness should not be less than 0.7cm, the exhaust channel setting, spruesetting, mould form, mold baking roasting temperature and casting mold temperature,mold cooling, the casting surface treatment method of different with cobalt chromium,nickel base alloy. Titanium in molten state is very lively, has long been unable to findsuitable and other material casting method, the cast titanium behind wrought titanium alloy 20 years. From 1956 to 1962 American Baer (Beal), developed by vacuum consumable arc melting technology of the Titanium Castings Solidification, officially entered the industrial production. In twentieth Century 70, began to be used in the field of Aeronautics and astronautics. From 70 time later, titanium alloy large thin-walled precision casting technology development and application. Based on thematerial performance is equal or close to the aviation titanium forgings, the cost is reduced by about 50%, and titanium casting technology has been rapid development.Expected in the near future, it will obtain the position and deformation of titanium alloyare equally important. Casting process and equipment of vacuum consumable arc skull furnace is the main equipment for production of titanium castings, the principle is:in the furnace body, using titanium material cast or forged bar as the parent material electrode (anode), water-cooled copper crucible as a positive electrode, under vacuum atmosphere, low input voltage (25 ~ 40V) of high current, the poles near thearc, melting titanium material consumable electrode tip, drop into the crucible, the formation of molten pool. In the cooling effect, a layer of shell forming copper cruciblewall and the crucible melt pool, protection against erosion, titanium liquid without pollution. When the weld pool growth crucible to suffici

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