Sunday, February 27, 2022

Common titanium alloy materials and titanium products preservation requirements:

1) For the site or warehouse where Grade 12 Ti-0.3Mo-0.8Ni Titanium Sheet products are stored, it should be selected in a clean and tidy place with smooth drainage, away from factories and mines with harmful gases or dust. Weeds and all debris should be removed from the ground to maintain the cleanliness of titanium materials.

2) Do not stack with acid, alkali, salt, Shimin soil and other materials that are corrosive to titanium materials in the warehouse. Different varieties of titanium materials should be sorted and stacked to avoid confusion and contact with corrosive objects.

3) Titanium alloy materials such as large titanium tubes, titanium rods, thick titanium plates, large diameter titanium tubes, and titanium forgings can be stacked in the open air.

4) Small and medium-sized titanium, titanium plates, titanium rods, medium-diameter titanium tubes, titanium wires, etc. can be stored and placed in a shed with satisfactory ventilation.

5) Small-scale titanium materials, thin titanium plates, titanium strips, small-diameter or special-shaped titanium tubes, various cold-rolled and cold-drawn titanium materials, and high-priced and easily corroded metal products can be stored and stored.

6) The warehouse is required to maintain a suitable storage background, pay attention to ventilation in sunny days, and close it to prevent moisture in rainy days.

7) The warehouse should be selected according to the geographical conditions, and the ordinary closed warehouse should be used if it is considered appropriate, that is, the warehouse with the roof and the wall, the door is tightly closed, and the ventilation device is installed.

Thursday, February 24, 2022

Classification of targets

According to the application, it mainly includes targets for semiconductor applications, targets for recording media, targets for display films, optical targets, and superconducting targets. Among them, Titanium Nitride Sputtering Target for semiconductor applications, targets for recording media, and display targets are the three types of targets with the largest market scale.

Titanium Rotary Sputtering Target shapes include cuboid, cube, cylinder, and irregular shapes. The cuboid, square and cylindrical targets are solid. During the sputtering process, the annular permanent magnet establishes an annular magnetic field on the surface of the target, forming an etched area on the annular surface with equidistant distances between the axes. The disadvantage is that the film deposition thickness is uniform. The performance is not easy to control, and the utilization rate of the target is low, only 20%~30%. At present, the rotating hollow tube magnetron sputtering target is popularized at home and abroad.

Wednesday, February 23, 2022

Internal defect correction process of titanium alloy tube and titanium tube weld

Internal defects of Grade 2 Pure Titanium Pipe welds Incomplete penetration refers to a defect that the workpiece is not fused with the weld metal or the weld layer. Incomplete penetration weakens the working section of the weld, resulting in severe stress concentration, which greatly reduces the strength of the joint, which often becomes the source of weld cracking. The slag inclusion weld contains non-metallic slag, which is called slag inclusion. Slag inclusion reduces the working section of the weld, resulting in stress concentration, which will reduce the strength and impact toughness of the weld.

When the stomatal weld metal is at high temperature, it absorbs too much gas (such as H2) or gas (such as CO) due to metallurgical reactions inside the molten pool, which cannot be discharged in time when the molten pool cools and condenses, and forms inside or outside the weld. Holes are stomata. The existence of pores reduces the useful working section of the weld and reduces the mechanical strength of the joint. If there are penetrating or continuous pores, it will seriously affect the sealing of the weldment. Cracks During or after welding, the partial rupture of the metal in the area of ​​the welded joint is called a crack. Cracks can occur in the weld as well as in the heat-affected zone on both sides of the weld. Sometimes it happens on the outside of the metal, sometimes it happens inside the metal.

Usually, according to the different mechanisms of cracks, they can be divided into two categories: hot cracks and cold cracks. Hot cracks occur during the crystallization process from liquid to solid in the weld metal, and most of them occur in the weld metal. The main reason for this is the presence of low melting point substances (such as FeS, melting point 1193 ° C) in the weld, which weakens the connection between the grains. . When the welding parts and electrodes contain a lot of impurities such as S and Cu, thermal cracks will easily occur. Hot cracks are characterized by spreading along grain boundaries. When the crack penetrates the surface and communicates with the outside world, it has a significant tendency to hydrogenate. Cold cracks occur during the post-weld cooling process, mostly on the base metal or the fusion line between the base metal and the weld. The main reason for its occurrence is that the heat-affected zone or the weld constitutes a quenching structure. Under the effect of high stress, the internal fracture of the grain is caused. When welding easily quenched titanium alloys with higher carbon content or more alloying elements. , most prone to cold cracks. Too much hydrogen melted into the weld can also cause cold cracks. Crack is one of the most dangerous defects. In addition to reducing the load-bearing section, severe stress concentration will occur. During use, the crack will gradually expand and eventually cause damage to the component. Therefore, this disadvantage is usually not allowed in the welding layout, and once found, it must be removed and re-welded.

Sunday, February 20, 2022

Complete Annealing Process of Titanium and Titanium Alloys

In the complete annealing process, the purpose of complete annealing of titanium and titanium alloys is to obtain a stable, plastic or microstructure corresponding to certain comprehensive properties. Recrystallization mainly occurs in this process, so it is also called recrystallization annealing. In addition, there are also changes in the composition, morphology, and quantity of a-phase and β-phase. Most a and a+beta titanium alloys are used in fully annealed condition. The two-phase region of all-a-type titanium alloys is very small, and recrystallization occurs mainly during the complete annealing process. The annealing temperature is generally selected to be 120 to 200°C below the a+β/β transformation point. Too high temperature will cause unnecessary oxidation and grain growth, and too low temperature will cause incomplete recrystallization. The cooling rate has little effect on the structure and properties of such alloys, and air cooling is generally used.

In addition to recrystallization during annealing, near-a titanium alloys and a+β titanium alloys also have changes in the composition, quantity and morphology of a-phase and β-phase, and it is also complicated to determine the annealing process. For the delivery state of the metallurgical plant, a stable and plastic structure is mainly required. The annealing temperature is generally selected to be 120-200°C below the a+β/β transformation point, and the cooling method is also air-cooled. However, for the annealing of the product before the final use, it must be determined through experiments according to the influence of the annealing process on the microstructure and mechanical properties.

As for metastable beta titanium alloys, complete annealing is also solution treatment. The annealing temperature of the metallurgical plant before leaving the factory is generally selected to be 80 to 100 °C above the a+β/β transformation point. Within the recommended full annealing process range, the specific process should be determined experimentally based on the processing history of the material, the actual chemical composition, and the equipment used. In order to avoid unnecessary oxidation, the process should be selected with the lowest temperature and shortest time under the premise of meeting the performance requirements.

The beta annealing process has appeared in recent years. The grade 7 titanium alloy plate and a+β titanium alloy are heated in the β phase region and then air-cooled, and a needle (or flake) a is precipitated on the coarse β grains. This structure corresponds to higher fracture toughness, creep resistance and notch sensitivity, but reduces plasticity indicators such as section shrinkage. It can be used as appropriate in situations where this performance is emphasized.

In addition, for some alloys, when it is required to improve the performance stability of long-term operation at the service temperature, a second annealing higher than the service temperature, or isothermal treatment is often used, such as TC9 and tc6 alloys.

Thursday, February 17, 2022

Development characteristics of titanium alloy materials and processing technology of titanium products

Due to the high manufacturing cost of titanium alloys, in order to reduce costs, the competitiveness of titanium alloys in the entire metal material market is improved at lower prices. Titanium is widely considered to have unparalleled superior properties compared to other materials, but the price of titanium is often prohibitive for consumers, especially automakers. The emergence of high-quality and low-cost titanium alloys will certainly contribute to the popularization and application of titanium and Ultra-Thin Titanium Alloy Sheet.

From the application status at home and abroad and the development of titanium processing technology, the plastic processing technology of titanium and titanium alloys will develop in the following directions in the future:

1) High performance, that is, to develop alloys with higher service temperature, higher specific strength, higher specific modulus, better corrosion resistance and wear resistance.

2) Multifunctional, that is to develop titanium alloys with various special functions and uses, such as high damping, low expansion, constant resistance, high resistance, anti-electrolytic passivation and hydrogen storage, shape memory, superconductivity, low modulus biomedical and other titanium alloys, and further expand the application of titanium and titanium alloys.

3) Deepen the research on traditional alloys, improve the practical properties of existing alloys, and expand the application scope of traditional alloys through the improvement of equipment and processes.

4) Adopt advanced processing technology and large-scale continuous processing equipment to develop continuous processing technology, direct rolling technology, cold forming technology and near-net forming technology to improve the production efficiency, yield and product performance of ASTM F67 Gr2 Titanium Plate.

5) Reduce costs, develop alloys that contain no or almost no precious metal elements, and add cheap elements such as iron, oxygen and nitrogen, and develop titanium alloys that are easy to process and form, easy to cut, and inexpensive to alloy elements and master alloys. Develop titanium alloys, use prohibited materials, and improve the recovery rate and utilization rate of prohibited titanium. This is particularly important for reducing the cost of civilian titanium alloys.

6) Using advanced computer technology to simulate the deformation and processing process of the workpiece, predict the evolution of the metal microstructure, and even predict the mechanical properties of the product (yield strength, tensile strength, elongation and hardness, etc.). ), and design or improve molds and tooling; analyze and process test results, reduce test volume, improve work efficiency, and reduce development costs.

Tuesday, February 15, 2022

Russia develops new technology to enhance antibacterial effect of titanium alloy

The Russian State Research University of Technology and other Russian scholars have developed a new technology that enables the antibacterial effect of astm b348 titanium rod, one of the key materials for advanced surgery. Implants processed according to the new method will significantly speed up and facilitate recovery from trauma, the researchers say.

The mechanical properties and resilience of damaged bones decline significantly with age, and such damage requires long-term treatment. The use of implants made of unmodified metals and alloys can lead to complications that may require a second surgical procedure afterward. Materials that can inhibit bacterial activity help in vivo implant surgery to be safer and more reliable. For this reason, Russian scholars have developed a method of spraying antibacterial coatings on Ti-Zr-Nb, one of the Titanium Alloy Rectangular Tube.

Experiments showed that treatment according to the new method completely inhibited the growth of E. coli on the implant surface. At a low dose of silver (about 0.037 mg/L), it is completely safe for the body and achieves a significant antibacterial effect. The "strike" against the bacteria is carried out by silver ions, the researchers said. The scientists chemically synthesized the nanoparticles that released them in a complex alcohol solution, which made them only about 10 nanometers in size. Thanks to this, silver is deposited in the pores of the material to a depth of 60 nanometers, greatly improving the durability and antimicrobial effect of the coating.

Thursday, February 10, 2022

Titanium alloy rod hot extrusion forming process!

The thermal conductivity of the titanium alloy billet is low, and the temperature difference between the surface layer and the inner layer will be large during hot extrusion. When the temperature of the extrusion cylinder is 400°C, the temperature difference can reach 200~250°C. Under the combined influence of suction strengthening and the large temperature difference of the billet section, the metal on the surface and the center of the billet has completely different strength and plasticity, which will cause very uneven deformation during the extrusion process, and produce a large additional tensile force on the surface layer. Stress becomes the source of cracks and cracks on the surface of extruded products. The hot extrusion process of titanium rectangular rod and titanium alloy rod products is more complicated than that of aluminum alloy, copper alloy and even steel, which is determined by the special physical and chemical properties of titanium rod and titanium alloy rod.

The research on the metal flow dynamics of industrial titanium alloys shows that there are great differences in the metal flow behaviors of different alloys in different temperature regions. Therefore, one of the main factors affecting the extrusion flow characteristics of titanium rods and titanium alloy rods is the heating temperature of the billet that determines the state of mental transformation. Compared with the temperature extrusion of the P-phase region, the metal flow in the a-phase region or the P-phase region is more uniform. It is difficult to obtain extruded products with high surface quality. Until now, the extrusion of medical titanium rod had to use lubricants. The main reason is that titanium will form eutectic with iron-based or nickel-based alloy mold materials at 980 degrees and 1030 degrees, which will cause strong mold wear.

Tuesday, February 8, 2022

What are the technical requirements for titanium rods?

Titanium rod has good physical and chemical properties, low density, light weight, non-magnetic, high strength, good corrosion resistance, it has good mechanical properties and welding performance, Baoji titanium rod is widely used in chemical equipment, seawater In desalination, ship parts, electroplating industry, etc., the corrosion resistance of titanium is 10 times that of ordinary stainless steel, and titanium metal is a metal with low human rejection, so the processed parts of medical titanium rods are widely used in human implantation and medical equipment. use. medical titanium bar

skills requirement:

1. The chemical composition of titanium and titanium alloy bars shall comply with the provisions of GB/T 3620.1. When the purchaser re-inspects, the allowable deviation of the chemical composition shall comply with the provisions of GB/T 3620.2.

2. The diameter or side length of the hot-worked bar and its allowable deviation shall comply with the provisions of Table 1.

3. After hot processing, the bar is turned (ground) and cold-rolled. The allowable deviation of the diameter of the cold-drawn bar should meet the requirements of Table 2.

4. The out-of-roundness of the bar that has been turned (ground) after hot processing should not be greater than half of its dimensional tolerance.

5. The indefinite length of the processed bar is 300-6000mm, and the indefinite length of the annealed bar is 300-2000mm, and the fixed or double length should be within the range of the indefinite length.

Monday, February 7, 2022

How to deal with burrs in titanium plate processing

The method of this mechanical treatment is: bury the Grade 1 Pure Titanium Plate in a lot of abrasives, add some grinding and polishing compounds dissolved in water, use the principle of oscillation to mix the abrasives with the material, and continuously ask the workpiece to scour, the surface and edges of the workpiece. Corners, etc. are ground by abrasives and then polished. This technology can be used for deburring, chamfering, rust removal, descaling, flattening and finishing processing for metal parts of various sizes and shapes.

Abrasives can be alumina (including fused, sintered or natural), corundum, plastic, quartz, ceramics, etc., and can be a single species or a mixture of several. The shapes of these abrasives can be made into diagons, cylinders, diamonds, etc. The reason why preformed abrasives are made first is that it is more economical and abrasive than any shape and natural shape materials. According to the shape and size of the workpiece, use abrasives of different shapes and sizes. Rolling abrasives include pumice, quartz, granite leather corners, shells, iron filings and ceramic fragments. The size of the abrasive particles should be larger or smaller than each hole in the part. The amount of content in the drum is also an important factor affecting the quality of the agricultural surface of the parts. The number of people in the drum is usually 70% of the drum volume. The solution in the drum should be added to about 95% of the drum volume (note: when adding acidic solution to the drum, you should add enough water first, and then add acid to avoid corrosion of parts during the rolling process, because the time increases , the concentration of the contained solution gradually decreases, and even loses its effect.

The processing time of Grade 7 Titanium Sheet can range from several minutes to several hours. The key is to choose the abrasive, which is determined by experiment. Only in this way can a uniform, bright appearance be achieved. After processing, the workpiece is unloaded together with the abrasive, which is screened by the separator and taken out, and the recovered abrasive can be continuously returned to the machine for processing. Oscillating finishing machine is divided into two categories: single machine and online, which are selected according to production needs.