The influence of laser welding on the surface treatment of titanium rods!

The process parameters of laser welding are difficult to grasp, because the thermal efficiency fluctuates greatly during the welding process, and the surface condition of the welded titanium rod has a great influence on the thermal efficiency: the brighter the surface, the larger the emitted laser light, and most of the laser energy is reflected to other objects , In the form of "heat" to the surrounding materials or media. But the thermal efficiency will suddenly change. Before the titanium metal rod is melted, only about 10%-20% of the light energy is absorbed by the titanium metal rod and heats the titanium metal rod. When the temperature rises to the melting point of the weld metal and starts to melt, the light absorption rate of the Grade 5 Ti-6Al-4V Titanium Bar increases sharply . The titanium rod company tells you that at this time, about 60%-80% of the light capacity is absorbed by the metal, and the sudden change in the thermal effect can easily cause the weld to burn through.

In order to avoid or reduce this adverse effect, ASTM F136 6Al-4V ELI Titanium Bar tells you that you can take corresponding measures, such as welding titanium metal rods; roughening the surface, using pulsed laser beams; adjusting the input energy; adjusting the spot size; changing the attenuation wave Pulse width and steepness.

A natural ruby ​​crystal containing alumina and dissolving low concentration of chromium atoms is used as the working material of the laser generator, which is called a solid-state laser generator. If CO2 is used as the working substance of the laser generator, it is called the force gas laser generator.

At present, the power of the laser welding machine is only kilowatts, and the price is expensive, the welding cost is high, and the application range is not wide. It is only used for the solder joints of some small parts in the production of some instruments and meters, especially when some solder joints are hidden and cannot be welded by ordinary welding methods. Multi-station welding can be realized by using laser beam, optical fiber and deflection prism.

What is the difference between titanium wire and titanium welding wire

Pure titanium wire is divided into structural titanium wire, titanium welding wire, titanium hanger wire, medical titanium wire, etc. according to its chemical composition. The chemical composition of titanium wire for structural parts is implemented in accordance with GB/T3620. There are many implementation standards for the chemical composition of titanium welding wire, and the commonly used titanium wire manufacturers are GB/T3623, AWS A5.16. The chemical composition requirements of titanium wire for structural parts are stricter. The standard composition requirement of titanium wire is lower than that of GB/T3620, so the price is also lower, and the market price is between 80 and 100. The chemical composition requirements of medical titanium wire are generally consistent with those of GB/T3620, but the hydrogen content should not exceed 0.01%.

Titanium welding wire is a series of titanium welding filler wires to solve the welding of standard titanium and titanium alloys such as TA1, TA2, TA3, TA5, TA6, TA7, TC1, TC2, TC4, TC6, TC9, TC10, TC11, etc. These filler metals are usually used to weld industrial pure titanium. In these filler metals, from ERTi-1 to ERTi-4, impurity elements gradually increased slightly. ERTi-5 Titanium Alloy Welding Wire TA5 Welding Wire This filler metal is mainly used to weld Ti-6Al-4V alloy commonly referred to as "6-4" titanium and is the most widely used in titanium tig welding wire. ERTi-6 titanium alloy welding wire TA6 welding wire is mainly used for welding Ti-5Al-2.5Sn alloy, which has good weldability. The weld metal formed by the filler metal of TC1 welding wire has excellent corrosion resistance, and its mechanical and physical properties are similar to ERTi-2. Titanium plate ERTi-9 titanium alloy welding wire TC9 welding wire, the filler metal of aluminum and vanadium content is about the average in ERTi-5, so it is also called "semi 6-4" titanium.

Processing technology of titanium and titanium alloy block

Plastic processing of titanium and titanium alloys has the characteristics of large deformation resistance, plastic difference at room temperature, high yield limit and strength limit ratio, large springback, sensitivity to notches, easy adhesion to the mold during deformation, and easy absorption of harmful gases when heated. Plastic processing is more difficult than steel and copper. Therefore, the processing technology of titanium and titanium alloys must take these characteristics into consideration. Titanium adopts plastic processing, the processing size is not limited, and it can be mass-produced, but the yield rate is low, and a large amount of scraps and residues are generated during the processing.

Aiming at the above shortcomings of titanium plastic processing, powder metallurgy technology for titanium alloy blocks has been developed in recent years. The powder metallurgy process of Grade 5 Ti-6Al-4V Titanium Wire is the same as ordinary powder metallurgy, but the sintering must be carried out under vacuum. It is suitable for the production of large-volume, small-sized parts, and is especially suitable for the production of complex parts.

This method requires almost no processing and has a high yield rate. It can not only make full use of titanium waste as raw materials, but also reduce production costs, but it cannot produce large-size titanium parts. The powder metallurgy process of titanium is: titanium powder (or titanium alloy powder)-screening-mixing-press forming-sintering-auxiliary processing-titanium products. The processing in the above process refers to plastic processing and casting. Plastic processing methods include forging, extrusion, rolling, stretching and so on.

The Grade 9 Ti3Al2.5V Titanium Pipe ingot is processed into various sizes of cakes, rings, plates, pipe trees, bars, profiles and other products. Casting methods can also be used to pores, and the corrosion resistance is reduced; therefore, inert gas or vacuum protection is used when titanium welding; welding; Recrystallization is easy to occur in the place, especially β-titanium, which causes coarse crystals, resulting in a decrease in ductility at this place; in addition, the deformation of titanium is large when welding, and it is difficult to correct.

What are the applications of titanium wire and titanium alloy wire

Titanium and titanium alloy materials, as the best in metal materials, have a series of excellent properties that other metal materials can’t match. Therefore, they have developed rapidly in recent years and have been rapidly and widely used in high-tech fields such as aerospace and military industries. Grade 1 Pure Titanium Wire manufacturers in the United States, Russia, Japan, China and other countries all over the world attach great importance to the research and development of titanium alloys, continue to develop new types of titanium alloy materials, and expand the application of titanium and titanium alloys. Due to the continuous deepening of research and the increase of product series, many titanium products, such as titanium wire, have increasingly entered the fields of various civilian consumer products.

1. Classification of titanium wire

Titanium can be divided into pure titanium and titanium alloy based on whether it contains alloying elements, and titanium alloy can be divided into α titanium alloy and near α type alloy, (α+β) type alloy, and near β type according to its composition and room temperature structure. Alloys and β-type alloys. Titanium and titanium alloys can be used to produce wires with different usage requirements according to different properties. The finished products of titanium and Gr2 Pure Titanium Wire are generally hard (Y) and annealed (M).

2. Application of titanium wire

Pure titanium wire has good corrosion resistance, high specific strength, non-magnetic, high biocompatibility, low impedance to ultrasound, high sound transmission coefficient, hydrogen storage and better shape memory function. The excellent characteristics of use value have produced important applications in many fields such as aerospace, petrochemical, medical and health, automobiles, construction, and sports and leisure products.

Application of titanium rod in tableware industry

Titanium is called smart metal and healthy metal. Titanium rods can be divided into pure titanium rods and titanium alloy rods. Pure titanium polished rod material: TA2; titanium alloy polished rod model: TC4 (GR5). With the increasing awareness of titanium metal, titanium metal has gradually been used in the tableware industry, in which titanium rods are used to process Grade 1 Titanium Plate chopsticks and titanium alloy chopsticks. Among them, titanium alloy rod processing chopsticks have higher gloss, but the disadvantage is that they are expensive, high hardness, and difficult to process; pure titanium chopsticks are also brighter after polishing, but the gloss is still slightly lower than that of titanium alloy. However, the performance-to-price ratio is still much higher than that of titanium alloys. First, the price of pure titanium rods is much lower than that of titanium alloy rods. Second, the hardness of pure titanium rods is better than that of low-pressure casting, so the processing cost is also lower. The specific choice of titanium rod processing depends mainly on the price accepted by the user.

The two materials of titanium rods do not contain heavy metals for environmental protection and health; the content of Gr5 Ti-6Al-4V Titanium Plate is not corroded by strong acids and alkalis, and when foods and beverages come into contact with condiments such as vinegar and salt, various foods will not rust; titanium has a natural sterilization effect. The surface of the chopsticks will not breed bacteria, and always maintain the safety and health of people's diet.

How does the principle of corrosion resistance of titanium plate come about?

As we all know, titanium plate is a kind of metal material with great corrosion resistance? So how exactly is the corrosion resistance of titanium produced? In the mysterious titanium world, let us solve its mysteries one by one. Titanium plus tool corrosion resistance, so everyone usually thinks it is an inert metal, but on the contrary, Molybdenum Sputtering Target is actually a very active metal, its equilibrium potential is very low, and the thermodynamic corrosion tendency in the medium is large, but in fact, Titanium is very stable in many media. For example, Grade 7 Titanium Plate is corrosion-resistant in oxidizing, neutral, and weakly reducing media.

This is because the titanium rectangular rod has a great affinity with oxygen. In the air or in an oxygen-containing medium, a dense, strong adhesion and inert oxide film will form on the surface of the titanium, which protects the titanium matrix from corrosion. Even due to mechanical wear, it will quickly heal itself or regenerate an oxide film. This indicates that titanium is a metal with a strong tendency to passivation, and the titanium oxide film always maintains this characteristic when the medium temperature is below 315℃.

Application of Titanium Alloy in Onshore Oil and Gas Exploration and Development

Oil and natural gas exploration and development can be divided into land exploitation and offshore exploitation. The oil and natural gas contained in the earth's crust roughly accounts for 60% of the land and 40% of the offshore oil. There is also the exploitation of offshore oil and gas in the submarine crust such as the Bohai Sea and the South China Sea. Significantly.

Before the industrialization and large-scale application of Grade 1 Titanium Plate, the shells of commonly used logging tools were made of 45 steel, 40Cr steel, and 30 MoVNb steel, but none of them could meet the needs of modern logging technology. Modern high-tech oil and gas exploration And the development requires that the metal shell of the logging tool can withstand the pressure> 98 MPa, but also resist the corrosion of underground crude oil and various media. In addition, it has a low absorption rate of natural γ-rays during logging. , It should not have a shielding effect on the earth's magnetic field. From these performance requirements, Gr5 Ti-6Al-4V Titanium Plate is a good material for the casing of logging tools.

Cutting performance of titanium alloy plate material

The high-efficiency cutting technology of titanium alloy materials is the key technology that the industry pays attention to, which fully reflects the connotation of "science and technology is the first productive force". Through the cutting practice of titanium alloy material blisk and compressor casing, it summarizes the titanium alloy cutting characteristics, cutting tool materials, tool structure, acquisition of titanium alloy high-efficiency cutting parameters, and the technology adopted to improve tool durability and processing efficiency. Countermeasures, I hope it can serve as a reference.

In order to improve the reliability and thrust of the engine, advanced and high-performance engines have adopted a large number of new materials, their structures are becoming more and more complex, and the requirements for machining accuracy are getting higher and higher, which puts forward higher requirements on the manufacturing process. In the improvement of the performance of the new generation of aero-engines, the contribution rate of manufacturing technology and materials is 50%~70%; in terms of engine weight reduction, the contribution rate of manufacturing technology and materials accounts for 70%~80%, which also fully shows that advanced High-quality Grade 7 Titanium Sheet materials and processes are the keys to reducing weight, increasing efficiency and improving the performance of aero engines.

Titanium alloy materials are more and more widely used in the aviation field due to their excellent properties such as high specific strength, low density, corrosion resistance, high-temperature resistance, and good weldability. Based on the above advantages, titanium alloy materials have become the material of choice for some parts.

Cutting characteristics of titanium alloy materials:

Some physical and mechanical properties of titanium alloys have brought greater difficulty to cutting. The small deformation coefficient during cutting of titanium alloy increases the sliding friction distance of chips on the rake face and accelerates tool wear. Titanium alloy has a small thermal conductivity, and the heat generated during cutting is not easily transmitted, and it is concentrated in a small area near the cutting edge. The modulus of elasticity of Grade 9 Ti-3Al-2.5V Titanium Plate is small, and it is easy to produce bending deformation under the action of radial force during processing, which can cause vibration, increase tool wear and affect the accuracy of parts. Due to the strong chemical affinity of titanium alloy to the tool material, the tool is prone to bond wear under the conditions of high cutting temperature and large cutting force per unit area.

What are the welding requirements for titanium plates

Titanium will react with oxygen and other gases at high temperatures to cause hardening. The ductility of the welding gap will decrease when the Grade 12 Titanium Sheet manufacturer is welding, resulting in pores, and the corrosion resistance is reduced; therefore, inert gas or vacuum protection is used when welding titanium; Recrystallization is easy to occur, especially β-titanium, which causes coarse crystals, which leads to a decrease in ductility at the place; in addition, the deformation of titanium is large when welding, and it is difficult to correct.

The general welding methods of titanium: TIG, MIG, resistance welding, plasma welding, particle beam welding, laser welding, etc. After welding, annealing treatment for stress relief or solution aging treatment or even double solution aging treatment is required to improve its Strength, toughness and fatigue resistance; for such a wide range of applications, we should have some understanding of its properties. As a metal, Grade 1 Titanium Plate has three characteristics:

  1. Does not rust

  2. Light weight, density is only 4.51

　　3. High strength (tensile strength 28—160kgf/mm)

What matters should be paid attention to during the cutting process of titanium plate

In view of these chemical properties of titanium metal, what issues should be paid attention to during the cutting process of Grade 7 Titanium Sheet?

(1) If it is a semi-automatic cutting, the guide rail should be placed on the plane of the titanium plate, and then the cutting machine should be placed on the guide rail. Note that the order cannot be reversed.

(2) The cutting parameters should be appropriate, and should be reasonably determined according to the thickness of the titanium plate, so as to obtain a good cutting effect.

(3) Check whether the cutting nozzle is unblocked. If there is a blockage, it should be cleared in time.

(4) Before cutting the titanium plate, the surface should be cleaned and a certain space should be left, which can facilitate the blowing of slag.

(5) The distance between the cutting nozzle and the surface of the Grade 1 Titanium Plate should be appropriate, too close or too far is not good.

(6) The preheating of the titanium plate should be sufficient, so as not to affect the cutting process.

(7) If you are cutting workpieces of different sizes, you should cut small pieces first, and then large pieces.

The development trend of aviation titanium alloy

With the rapid development of aviation science and technology, in the face of increasing requirements for national defense construction, a new generation of aircraft must meet the requirements of ultra-high speed, high altitude, long endurance, and ultra-long range. In order to improve the reliability of aircraft, advanced aircraft and engines have increasingly increased the amount of high-performance materials such as titanium alloys, and their structures have become more and more complex. Therefore, aerospace titanium alloys will develop towards low-cost and high-performance, and at the same time continue to carry out independent research and development of new grades and the development of new processes.

Research on Strengthening Low Cost Aviation Gr23 Ti-6Al-4V ELI Titanium Sheet

The aviation industry’s requirements for materials pay more attention to the balance of performance and cost, and no longer blindly pursue high performance. Low cost will run through the entire life cycle of products such as material selection, structural design, manufacturing technology, testing and evaluation, and maintenance, reducing the cost of titanium alloys. It is the inevitable trend of industry development. Substituting ordinary Fe elements for expensive elements such as Nb, Mo, and V, and vigorously developing near-net forming technology will become the two key directions for reducing the cost of aerospace titanium alloy engineering applications.

Research on Strengthening High Performance Aerospace Titanium Alloy

Although titanium alloys have good comprehensive properties, the existing aviation titanium alloys still cannot fully meet the high-performance requirements of the aviation industry. At present, it is difficult for high-temperature Gr9 Ti-3Al-2.5V Titanium Bar to exceed 600°C in actual long-term use. The research on aviation titanium alloys above 600°C is still in the experimental and pilot stage, and there is still a long way to go to large-scale development and application. In addition, the batch stability research and application of flame-retardant titanium alloys, high-strength, high-toughness and damage-tolerant titanium alloys have become the focus of attention of many scholars. In the future, research on high-performance aviation titanium alloys will tend to dig deeper into existing alloys and develop research on new grades of alloys at the same time.

Do you know how to carburize titanium wire?

ERTi-5 Titanium Welding Wire forms a kind of stable carbide with higher hardness with carbon. The growth of the carbonized layer between titanium and carbon is determined by the diffusion rate of titanium in the carbonized layer.

The solubility of carbon in titanium is less than 850X: the total is 0.3%, while at 600C it drops to about 0.1% B. Because the solubility of carbon in titanium is small, basically only the deposition layer through the titanium carbide layer and its lower fork domain To achieve the purpose of surface hardening. Carburizing must be carried out under the condition of removing oxygen, because the hardness of the surface layer formed by the powder that is commonly used for steel carburizing against carbon monoxide or oxygen-containing carbon monoxide reaches 2700MPa and 8500MPa, and it is easy to peel off.

In contrast, under deoxidation or decarburization conditions, a thin layer of titanium carbide may be formed when carburizing in charcoal. The hardness of this layer is 32 OUOMPa, which is consistent with the hardness of titanium carbide.

The depth of the carburized layer is roughly greater than the depth of the nitrided layer when nitriding with nitrogen under the same conditions. Under the condition of oxygen enrichment, it must be considered that the absorption of oxygen affects the depth of hardening.

Only under the condition of very thin layer thickness can the carbon powder be infiltrated in a vacuum or argon-methane atmosphere to form sufficient adhesion strength. Compared with this, the use of gas carburizing agent may form particularly hard and good adhesion. Hardened layer of titanium carbide.

Traditional processing methods of titanium and titanium alloys

The traditional methods of titanium and titanium alloy processing mainly include ingot metallurgy (or plastic processing), casting and powder metallurgy. The process method of titanium and titanium alloy ingot metallurgy is to melt sponge titanium, intermediate alloy or pure metal into ingot, and then process it into Gr5 Ti-6Al-4V Titanium Foil material by cold and hot. Ingot processing methods include forging, rolling, extrusion, drawing, stamping and spinning, among which forging is the indispensable, most basic and most important method, followed by rolling, and a small part of titanium is extruded Spinning is a supplementary method for drawing materials, and the use is the least. These five titanium ingot processing methods have their own characteristics and are complementary. In the processing of ASTM B861 25*1.2mm Titanium Tube For Chemical and titanium alloy materials, if one method is not enough, it can be processed into finished or semi-finished titanium alloys of various shapes and specifications through several methods. The plastic processing of titanium alloy has the characteristics of large deformation resistance, low plasticity, high yield strength and tensile strength ratio, large springback, sensitivity to notches, easy adhesion to the mold during deformation, and easy oxidation when heated at high temperatures. The plastic processing ratio of titanium alloy Steel, copper and aluminum are difficult.

Several current surface treatment methods for titanium building materials in the world

According to the data, there are roughly six treatment methods for the surface of titanium materials. Now we will introduce and analyze them one by one:

1. Sandblasting method

The surface of the titanium material is sandblasted with a certain particle size shot blasting to make the surface of the titanium material rough. The surface reflectivity is reduced, and the disadvantage is that it is easy to deform the plate when processing the thin plate.

2. Pickling method

The surface is treated in the acid solution of HF + HNO3 to make the surface of the plate present the original color of Grade 16 Ti-0.5Pd Titanium Tube. The disadvantage is that the color is single, and the surface color consistency is easily damaged during use, which is relatively unsuitable for the decoration industry.

3. Rolling embossing method

After the surface of the roll is pretreated, the titanium plate is smoothed, so that the surface of the titanium plate produces regular unevenness. The key to this method is the surface treatment of the rolls. The existing domestic treatment methods are sandblasting, electric spark treatment, and laser treatment.

4. Anodizing method

The color tone control of this method uses an anodizing device to give a rated voltage, and as the voltage rises, the color changes. This method can be divided into direct current electrolytic anodizing method, alternating current electrolytic anodizing method, laser irradiation multicolor treatment in solution, thick film anodizing method and chemical oxidation method.

When the DC electrolysis setting voltage is a certain multiple of the AC electrolysis setting voltage, the same color can be obtained. According to the increase in voltage, the color changes as follows: gold, red purple, cyan, yellow, purple, cyan, cyan, green, yellow-green.

To carry out the colorful coloring treatment of the titanium material, the covering method and the anodizing treatment can be combined, but the process is complicated. The method of laser irradiation in the solution can be used to carry out the colorful treatment of Gr7 Ti-0.2Pd Titanium Plate. The method is to irradiate the titanium surface with laser in the solution. As the anodic oxidation and laser irradiation are carried out at the same time, the part irradiated by the laser is etched and the oxide film becomes thinner. During the secondary anodization of the laser-irradiated part, the resistance of the etched part is reduced and the current is large. The thickness of the oxide film formed during the formation of the oxide film is different from that of the part that is not irradiated by the laser, and the color is different. Repeat this many times to obtain Multi-colored titanium surface.

5. Rolling embossing method + pickling

It adopts the advantages of rolling method and pickling method, so that the titanium surface with regular unevenness reveals the metal color that titanium metal should have, and it can give people a noble and solemn feeling in application.

6. Sandblasting + coloring method

This method reduces the reflectivity of the surface of the board, and at the same time obtains the required surface color, which is also popular in the decoration industry.

What are the advantages of induction melting technology for titanium alloy forgings?

At present, the smelting method widely used in China's industry is the vacuum consumable electrode arc smelting method. Although it can effectively ensure that the alloy liquid has a certain degree of superheat and a more accurate alloy melt composition, this method has extremely high requirements for the quality of the raw electrode, and the surface area of ​​the molten pool is large and the depth is small, resulting in high vapor pressure elements (such as A1 The volatilization loss of the element) is very large, which is unfavorable for controlling the alloy composition.

The water-cooled copper crucible induction smelting method is to place a copper crucible that is split and cooled by water under an induction electromagnetic field for smelting, which can maximize the advantages of the induction smelting method. Between the water-cooled copper crucible and the metal melt, there is a solid shell layer produced by the solidification of the titanium flange melt, the so-called condensed shell. At this time, the crucible lining is equivalent to being made of molten metal, that is, the inner surface of the crucible has the same composition as the molten metal, which prevents the crucible from contaminating the molten metal. With the increase in the number of cold crucible combinations and the input power of the power supply, the strong magnetic field promotes the rapid melting of the charge and produces a strong stirring effect, so that the temperature and composition of the metal melt are uniform, and a consistent degree of superheat can be obtained. Due to the complex composition of the new titanium bar and TiAl compound alloy, the allowable deviation of the alloy element content is small, it is difficult to meet the requirements of the alloy composition by the common arc melting method of titanium alloy rod. Water-cooled crucible induction condensed shell melting is particularly suitable for this work. The molten alloy composition is uniform, and the superheat of the alloy liquid with the interstitial element content is appropriate, which meets the requirements of static and centrifugal casting.

Machining Process and Special Tool Design of Titanium Alloy Inner Cavity Cylindrical Surface

At present, the requirements of aerospace products for processing accuracy are continuously increasing, and the number of overall structural parts in the aerospace field is continuously increasing. High-precision thin-walled cavity parts are more and more widely used in the aerospace product industry. The machining accuracy control of the Grade 2 Titanium Tube electrode, especially the machining accuracy control of the servo system, is directly related to the requirements of many performance indicators of the weapon system. Titanium alloy blanks are generally used for such parts, and the material removal rate can reach 85%. At the same time, a significant production feature of this kind of parts is the variety, small batches, and even single-piece production. This structural feature and production method have determined that its manufacturing technology has always been in an unstable state, and processing and manufacturing have always been faced with difficulties such as long processing cycles, high processing costs, and difficult control of processing accuracy.

The material of the spherical ring frame is titanium alloy tc4, which is a single piece and small batch production. These parts are precision machined parts. The external dimension of the part is sφ108mm, and the wall thickness is 4mm. It is a thin-walled and difficult-to-machine material part, and has high requirements for shape and dimensional accuracy. Due to the integral cutting and forming, it is easy to deform during the processing, the material cutting performance is poor, and the part structure is also poor, which brings great difficulties to the processing. Therefore, choosing a reasonable processing method and the correct tool is the key to ensuring processing quality.

The spherical ring frame material is titanium alloy tc4, which is characterized by: poor thermal conductivity of titanium alloy is a metal material with poor thermal conductivity. During cutting, the contact area between chips and the rake face is small, which is particularly easy to cause thermal deformation of thin-walled parts. Tungsten Sputtering Target alloy has low elastic modulus and large elastic deformation. The modulus of elasticity of titanium alloy is 1078mpa (about 1/2 of steel). When cutting, the workpiece near the flank face has a large springback, resulting in a large contact area between the machined face and the flank face. As a result, the geometric dimensions and accuracy of the workpiece are poor, the surface roughness increases, and tool wear increases. Titanium alloy has a higher affinity and higher cutting temperature. During cutting, the titanium chips and the surface to be cut are occluded with the tool material, resulting in serious tool jamming, which is easy to cause tool jamming and wear. Titanium alloy has strong high temperature chemical activity. When the temperature exceeds 600, there is an interstitial solid solution containing oxygen and nitrogen. After the gas is absorbed, the surface hardness of the titanium alloy is obviously improved, which has a strong wear effect on the knife. Therefore, titanium alloy processing tools are required to have high strength, high toughness and high red hardness.

Development Trend of TC4 Titanium Alloy Heat Treatment Process

In view of the above-mentioned status quo of TC4 titanium alloy in today's heat treatment process, in its future development trend, the following points are summarized:

First, the two-state structure and Widmanstatten structure in TC4 titanium alloy have both advantages and disadvantages. Therefore, in future research, the defects of the two should be compensated for, so that the mechanical properties of TC4 titanium alloy can be obtained. Effective enhancement.

Second, because air cooling can improve the comprehensiveness of the mechanical properties, in the solution treatment process, when the cooling rate is studied, the air cooling should be studied emphatically. After the TC4 titanium alloy is air-cooled , Its own strength and hardness are effectively improved, so as to effectively enhance the mechanical properties of TC4 titanium alloy.

Third, the size of the α of the secondary phase depends on the effective temperature. Therefore, relevant scientific researchers should be aware of how to control the size of the α of the secondary phase in the actual effect process. Control the comprehensive mechanical properties of the TC4 titanium alloy to achieve the purpose of effectively enhancing the mechanical properties of the TC4 titanium alloy.

Fourth, because the aging time and aging temperature of TC4 titanium alloy have similar changes in mechanical properties, relevant scientific researchers should conduct in-depth research on the aging time of titanium welded tubing.

Fifth, since the equipment of cryogenic treatment process is relatively expensive, the specific mechanism is not yet understood, and it has not been widely used at this stage. Therefore, the future research on cryogenic treatment equipment mainly focuses on how to get the cost. Effective reduction, only when the cost of the layer is reduced, can it be applied to various fields, which will help promote the development of Pickling Titanium Wire in the cryogenic treatment process.

What are the polishing methods for titanium rods and titanium alloys?

What are the polishing methods for titanium rods and titanium alloys? (1) Fine grinding. That is, the surface of titanium rods and titanium-containing alloy castings is lapped using conventional various types of emery rubber wheels. The problem that needs to be paid attention to during grinding is still not to cause the casting to generate heat, not to cause grinding damage on the surface of the casting, and to make the entire surface smooth.

(2) Barrel grinding method. The so-called barrel grinding method is to put the processed castings, abrasives, water and additives into the barrel-type grinding tank. The grinding barrel generates rotation and vibration, causing friction between the mixture of abrasives and the processed castings, and grinds the surface of the castings smoothly. ,smooth.

It is characterized by no dust pollution, low labor intensity, and no heat generation in the conventional grinding process. At present, Japan has commercialized barrel grinders and abrasive materials used for grinding Gr23 Ti-6Al-4V ELI Titanium Sheet and titanium-containing alloy castings, other metal castings and plastics.

(3) Mechanical polishing method. Use different specifications of soft cloth wheels or black brushes, dipped in titanium and titanium-containing alloy special polishing paste to polish the surface of titanium and Grade 36 Titanium Wire. When polishing titanium castings, it is necessary to completely clear the contamination layer on the surface of the casting and no new grinding and hardening layer occurs, which will not achieve the desired polishing effect.

High-speed and light-pressure methods are still used for polishing. The author has also tried using green polishing paste to polish titanium and titanium-containing alloy castings, and achieved a relatively ideal polishing effect. The polished titanium and titanium-containing alloy castings cannot be washed immediately. The surface oxide film must be completely formed before washing, otherwise the surface will darken.

Titanium alloy industry chain

The industrial chain of the titanium industry can be simply divided into two, one is the industrial chain of non-ferrous metals: titanium ore→sponge titanium→titanium ingot→titanium material; the other is the industrial chain of chemical industry: titanium ore→titanium dioxide. These two industrial chains are closely related to each other in the upstream, but are independent of each other in the midstream and downstream.

The titanium non-ferrous metal industry chain can be divided into three major parts from top to bottom:

1) The upstream includes titanium ore resources such as ilmenite and rutile, as well as artificial rutile, titanium slag and Grade 1 Titanium Tube tetrachloride processed from ilmenite;

2) The middle stream is mainly divided into two parts: one is the reduction of titanium tetrachloride to generate sponge titanium; the other is the melting and casting of sponge titanium into titanium ingots, and then the preparation of titanium round rod processing materials including forgings, bars, plates, pipes, wires, wires, etc. ；

3) The downstream is mainly to further process titanium blanks according to the requirements of specific applications such as aerospace, petrochemical, nuclear power, ships, desalination, automobiles, sports medicine and other fields;

Titanium alloy grinding and polishing technology

(1) Fine grinding

That is, the surface of titanium and titanium alloy castings is polished by using conventional various types of emery rubber wheels. The problem that needs to be paid attention to during grinding is still not to cause the casting to generate heat, not to cause grinding damage on the surface of the casting, and to make the entire surface smooth.

(2) Barrel grinding method

The so-called barrel grinding method is to put the processed castings, abrasives, water and additives into the barrel-type grinding tank. The grinding barrel rotates and vibrates, causing friction between the mixture of abrasives and the processed castings to grind the surface of the castings. Smooth and flat. It is characterized by no dust pollution, low labor intensity, and no heat generation in the conventional grinding process. At present, Japan has commercialized barrel grinders and abrasive materials used for grinding Titanium Planar Target alloy castings, other metal castings and plastics. Tests have confirmed that the pk series abrasives have the highest grinding efficiency, but the surface roughness is also the highest. Although the grinding efficiency of SA and B series abrasives is not as good as PK, the surface smoothness of the titanium castings after grinding is the highest. At present, the Fourth Military Medical University has successfully developed the first dental barrel grinder in China.

(3) Mechanical polishing method

Use different specifications of soft cloth or black brush, dipped in ASTM F67 Gr2 Titanium Sheet and titanium-containing alloy special polishing paste to polish the surface of titanium and titanium-containing alloy. When polishing titanium castings, it is necessary to completely clear the contamination layer on the surface of the casting and no new grinding and hardening layer has occurred, which will not achieve the desired polishing effect. High speed and light pressure should be used when polishing. The author has also tried to use green polishing paste to polish titanium and titanium-containing alloy castings, and achieved a relatively ideal polishing effect. The polished Grade 23 Titanium Plate and titanium-containing titanium alloy castings cannot be washed immediately. The surface oxide film must be completely formed before washing, otherwise the surface will become dark.