What is the difference between 316Ti stainless steel and 316L stainless steel?

/in /by

316Ti stainless steel is based on 316 stainless steel by adding Ti to improve the resistance to intergranular corrosion. It is also a variant of 316 stainless steel and is used in equipment resistant to sulfuric acid, phosphoric acid, acetic acid, and acetic acid. Physical properties: 316 stainless steel chemical composition C: ≤0.08 Si≤1.00 Mn≤2.00 P≤0.035 S≤0.030 Ni 11.00~14.00 Cr 16.00~19.00 1 Mo 1.80~2.50 Ti≥5*C%~0.70 Usually also called Mo2Ti3163 (00Cr17Ni14Mo2) is an ultra-low carbon steel of 0Cr17Ni12Mo2, which has better resistance to intergranular corrosion than 0Cr17Ni12Mo2 (SUS316). 316L stainless steel chemical composition C≤0.03 Si≤1.00 P≤0.035 S≤0.03 Ni: 12.0-15.0 Cr: 16.0-18.0 Mo: 2.0-3.0 Tensile strength (Mpa) 620 MIN Yield strength (Mpa) 310 MIN Elongation ( %) 30 MIN Area reduction (%) 40 MIN Features: due to the addition of Mo, its corrosion resistance, atmospheric corrosion resistance, and high-temperature strength are particularly good, and can be used under harsh conditions; excellent work hardening (non-magnetic); Excellent high-temperature strength; non-magnetic in solid solution state; cold-rolled products have the good gloss and beautiful appearance; compared with 304L stainless steel, the price is higher.

copper-nickel-90-10-pipe

UNS C70600 in Seawater Service

/in /by
Read more

The performance and application of titanium forgings!

/in /by

Titanium forgings have high strength, low density, good mechanical properties, good toughness and corrosion resistance. In addition, titanium forgings have poor technological performance, are not easy to cut, are easy to absorb impurities such as hydrogen, oxygen, nitrogen, carbon, etc. during hot processing, and have poor wear resistance and complex production processes. The industrial production of titanium began in 1948, and with the development of the aviation industry, the titanium industry is growing at an average annual rate of about 8%. At present, the global annual output of it has reached more than 40,000 tons, and there are nearly 30 types of it. The most widely used titanium forgings are Ti-6Al-4V (TC4), Ti-5Al-2.5Sn (TA7) and industrial pure titanium (TA1, TA2 and TA3).

Titanium forgings are mainly used in the manufacture of compressor components for aircraft engines, followed by structural parts for rockets, missiles and high-speed aircraft. In the mid-1960s, titanium and its alloys were used in general industries such as making electrodes for the electrolysis industry, condensers in power stations, heaters in oil refining and desalination, and in environmental pollution control devices. Titanium and titanium alloys have emerged as corrosion-resistant structural materials. In addition, it is used in the production of hydrogen storage materials and shape memory alloys.

Standard: National Standard GB/T 16598-1996

American Standard: ASTM B381

Material: TA0, TA1, TA2, TA3, TC4

Delivery state: Annealed state (M) Hot working state (R) Cold working state (Y) (annealing, ultrasonic flaw detection)

Packing: carton or wooden box

Surface treatment: car light, chamfering

Surface quality: The surface roughness Ra of the two end faces should not be greater than 3.2m (subject to the requirements of ultrasonic flaw detection), and the surface roughness Ra of the inner and outer sides should not be greater than 12.5m (Ra should not be greater than 3.2 m during cylindrical ultrasonic flaw detection). Circumferential surface required), the chamfering radius is 5 ~ 15mm. There should be no visible defects such as cracks, folds, double skins, etc. on the surface of the product. Local surface defects can be removed by grinding, the cleaning depth should not exceed the dimensional tolerance, and the minimum allowable size should be guaranteed. The ratio of the cleaning depth to the width of the two end faces should not exceed 1: 6, the inner and outer sides should not exceed 1: 10, and the outer grinding should be carried out in the axial direction.

Well, the above is all about the performance and application of titanium forgings. I hope you like it!

Refinement of Titanium Alloy by Hydrogen Treatment

/in /by

Ultrafine-grained titanium alloy has a series of outstanding advantages, its room temperature strength can be improved to a certain extent, and it has a great elongation when stretched at high temperature. Refined grains are usually obtained by large deformation methods, such as equal-diameter angular extrusion, high-pressure torsion, multi-axis forging, and cumulative coil pressure welding. In addition, hydrogen treatment can also be used for titanium alloys.

In the 1970s, the Moscow Aircraft Manufacturing Research Institute studied the influence of hydrogen on the processing properties of titanium alloys, and proposed the concept of “hydrogen plasticization”, using hydrogen as a temporary alloying element, through hydrogen infiltration, eutectoid decomposition, vacuum hydrogen removal, and other processes. , using hydrogen-induced plasticity, hydrogen-induced phase transformation, and the reversible alloying of hydrogen in titanium alloys to improve processing properties and refine the microstructure of materials.

Hydrogen treatment can be used to refine the grain structure of titanium alloy castings and forgings and improve their mechanical properties. It has been reported in the literature that the microstructure of TiAl alloy can be refined by hydrogen treatment, and its compressive strength and yield strength have been significantly improved. In practical applications, the hydrogen treatment technology can usually be combined with the corresponding subsequent heat treatment and thermal deformation treatment, so as to obtain a very fine grain structure. Studies have shown that large-scale deformation of hydrogenated titanium alloys at a high temperature can form equiaxed fine grains with a grain size of about 1 μm, and even nano-scale grains. The research on Ti-6.3Al-3.5Mo-1.7Zr (%, mass fraction) alloy shows that the hydrogen atomic fraction is 14%-16% in hydrogen treatment, the deformation temperature is reduced to 550 ℃, and then through the deformation process and metastable phase, The decomposition process finally obtained nanocrystalline grains with a grain size of 40 nm. Comparing the engineering stress-strain curves of Ti-6Al-4V alloys with different grain sizes, it can be seen that the ultra-fine-grained materials exhibit high yield strength and high elongation compared with the coarse-grained or general fine-grained materials.

Let the titanium alloy absorb a large number of hydrogen atoms (protium), and then let these hydrogen atoms (protium) desorb under a high-temperature vacuum, this process is called protium treatment. For α + β titanium alloys, the protium treatment includes the following three processes: (1) protium absorption in a hydrogen atmosphere; (2) martensitic transformation and hot working eventually cause dispersive hydride precipitation; (3) final protium desorption treatment and recrystallization. It is reported that the Ti-6Al-4V alloy is treated with protium, and the alloy absorbs 0.5% of protium and desorbs at 873K, showing an ultra-fine equiaxed grain structure with large-angle grain boundaries and grain size in the range of 300-500 nm. Studies have shown that protium treatment increases the content of the β phase in the α matrix. Tensile tests show that the yield strength of the alloy increases at room temperature, and the maximum elongation of 1123K alloy reaches 9000%. It is also reported that the Ti-6Al-4V sheet was treated with protium with a protium content of 0.5%, then quenched at 1223K, hot-rolled at 1023K to a thickness reduction rate of 80%, and desorbed at 873K. In the uniform structure of equiaxed crystals, the grain size is 0.3 ~ 0.5μm. The test results show that the mechanical properties such as superplastic elongation of the alloy increase significantly with the decrease of grain size.

Although the hydrogen treatment method shows great potential for refining titanium alloys, compared with other conventional methods, the hydrogen treatment method has a higher cost, and for larger structural parts, this treatment method also suffers from uneven hydrogen distribution and equipment condition requirements. Higher problems still need further research to solve.

How to whiten 304 stainless steel plate?

/in /by

304 stainless steel plate is made of stainless steel, it will not rust, and it is also very strong. It is a common steel plate. Of course, it may be whitened in some special projects. But how is this whitening done?

1. What is the whitening treatment? Refers to the 304 stainless steel plate in the process of processing, which will be rolled, edged, welded, or heated by artificial surface fire, resulting in the removal of black oxide scale, the whitening treatment of traditional stainless steel surface is generally used hydrofluoric acid and nitric acid Corrosion method to remove, but this method is costly and pollutes the environment.

2. At present, there are sandblasting methods and chemical methods for the surface oxide scale treatment of 304 stainless steel plates. Sandblasting method: mainly uses the method of spraying micro glass beads to remove the black oxide scale on the surface. Chemical method: use a non-polluting pickling passivation paste and a non-toxic cleaning solution with inorganic additives at room temperature for dipping, so as to achieve the purpose of whitening the natural color of stainless steel, and it basically looks dull after treatment. This method is more suitable for large and complex products.

304 stainless steel plates may produce a certain amount of oxide scale in some processes. At this time, we can carry out whitening treatment. Sandblasting and chemical treatment are more appropriate methods.

Gold plated beryllium was used as NASA’s James Webb Space Telescope shiny giant mirror

/in /by

For one: why is it gold?

The primary mirror of the James Webb Space Telescope

The primary mirror of the James Webb Space Telescope

Have you seen images online of a giant, golden honeycomb poised to launch into space? That’s the iconic mirror that will allow the James Webb Space Telescope to study corners of the cosmos never before seen.

The James Webb Space Telescope, a joint collaboration between NASA, the European Space Agency, and the Canadian Space Agency, is set to be the most powerful space telescope ever. The secret to its impressive observation powers? An enormous, golden mirror. The mirror is made up of 18 smaller mirrors that together will allow mission teams to use the scope to measure light from extremely distant galaxies, billions of light-years away.

“What we really need is for all those 18 mirrors to act as though they’re a single monolith,” Lee Feinberg, the Optical Telescope Element Manager for Webb, told Space.com at a news conference in May of this year.

Webb is set to launch to space on Dec. 22 from the Guiana Space Center, or Europe’s Spaceport, in Korou, French Guiana.

Related: Building the James Webb Space Telescope (gallery)

Webb’s primary mirror spans 21 feet, 4 inches (6.5 meters) across, and is made up of 18 hexagonal mirror segments measuring 4.3 feet (1.32 m) in diameter. Webb also has a small secondary mirror that measures just 2.4 feet (0.74 m) across.

This makes Webb’s primary mirror significantly larger than that of the Hubble Space Telescope, which has a mirror that measures 7.8 feet (2.4 meters) across.

Focusing on a giant hexagon

the telescope's infrared view will be able to penetrate interstellar dust

the telescope’s infrared view will be able to penetrate interstellar dust

The space telescope’s signature honeycomb mirror segments are shaped as such because the pieces can fit together in a way that makes it possible for the primary mirror, made up of all of the pieces, to be a roughly circular shape, according to a NASA statement(opens in new tab).

“If the segments were circular, there would be gaps between them,” the statement reads, adding that “a roughly circular overall mirror shape is desired because that focuses the light into the most compact region on the detectors. [An] oval mirror, for example, would give images that are elongated in one direction. A square mirror would send a lot of the light out of the central region.”

In addition to its shape that helps it to pick up light from very far away, Webb’s mirror operates with the help of what is called actuators. Actuators are tiny mechanical motors that help the mirror to focus on far-off objects.

There are six actuators on the back of each mirror piece that can move each piece of the mirror in minuscule amounts very slowly, allowing the mission team to fine-tune Webb’s view.

“These actuators are actually a pretty amazing piece of engineering in the sense that they can move long strokes, called core stage, but they also have a fine stage which can move extremely precise, fractional wavelengths of light,” Feinberg said.

Why is it gold?

The James Webb Space Telescope’s 21.3-foot (6.5 meters) diameter primary mirror.

Aside from its hexagonal shape and enormous size, Webb’s most distinctive feature is the shiny, bright gold color of its mirror.

It has such a striking appearance that NASA even held an art challenge (opens in a new tab)open to public submissions of art inspired by the space telescope.

So, “why gold?” Feinberg said. For one, it is extremely reflective (which is readily apparent in its brilliant appearance). “It has this amazing reflectivity … gold actually has the highest reflectivity over a very wide wavelength band.”

“The reason you build such a large telescope is to catch every individual photon,” he added. “So you also want the reflectivity of each of these coatings to be extremely high so we don’t lose photons along the way.”

Webb’s mirrors are said to be 98% reflective — meaning they reflect 98% of incoming photons — which is about as reflective as it comes.

Feinberg added that “it’s also a protective gold that has an overcoat … it’s a very rugged coating.”

Now, while Webb’s mirror segments are coated in gold, they are not made of solid gold. They are actually constructed from beryllium, a strong but lightweight metal. Each mirror piece weighs about 46 pounds (20 kilograms) on Earth. In addition to being extremely durable while comparably lightweight, beryllium can also hold its shape at the extreme cold temperatures that Webb will need to operate at, according to the NASA statement.

Making something amazing(ly cold)

Webb has been over 20 years in the making since development first began on the scope in 1996.

To develop, build and test Webb’s mirrors, it took “a product integrity team that was made up of optical experts from all around the world,” Bill Ochs, the James Webb Space Telescope project manager, said during the same news conference.

Ochs shared that they tested the hardware “at [NASA’s] Johnson Space Center in their chamber that was built back in the Apollo era that was modified to become the largest cryogenic chamber in the world.”

In this cryogenic chamber, which is a facility that creates an extremely cold environment, “we were able to deploy the entire telescope,” Ochs said.

To peer out into the farthest reaches of the universe and spot its stars and galaxies, Webb observes in infrared light. However, since infrared light is essentially heat, if Webb were too warm it wouldn’t be able to detect infrared light past the glow of its own mirror.

In fact, Webb’s mirrors need to be at about minus 364 degrees Fahrenheit (minus 220 degrees Celsius) to work as intended. To keep it this cold, the scope will be sent into deep space where it will deploy sun shields to shade its mirrors and other instruments from any lingering warmth from the sun.

So, with this testing, the team was able to ensure that Webb’s precious mirror pieces could operate in such extreme and frigid conditions.

Common quality problems and solutions of titanium-steel clad plates

/in /by

Titanium-steel clad plate is produced by explosive compounding or explosion-rolling compounding, which has both excellent properties and low cost. In explosive composite production, the common quality problems of composite panels are mainly failure to fit after an explosion, insufficient bonding rate, insufficient bonding strength, and local surface defects of a titanium layer and steel layer such as pits, cracks, etc. The main reasons are
The problem of non-fitting of explosions is mainly due to improper selection of explosion process parameters, inappropriate selection of explosives, and appropriate gaps, which will result in a large number of explosions that do not fit or the gas in the gaps is not completely discharged, resulting in local hollowing; especially in After annealing and heat treatment, due to the thermal expansion of the gas, the cladding bulge will form a local bulge.
The problem of low bonding strength is mainly caused by inappropriate explosive welding parameters, such as a small number of explosives, a small gap, or a large area of ​​melting.
The problem of large-area melting is mainly caused by the fact that the gas that is too late to escape is trapped on the bonding interface and is subsequently compressed adiabatically under high pressure. After prying open the cladding and the substrate, it can be found, that is, the phenomenon of false bonding.

In response to these problems, the preventive measures that need to be taken during manufacture are mainly as follows:
1. Adhere to the incoming material re-inspection system, and the bonding condition of the composite board should be non-destructively tested one by one. The focus is on areas such as sheet edges, detonation points, etc. 100%UT+100%PT detection can be performed.
2. The mechanical properties of the composite plates are re-examined one by one to verify the shear properties after annealing to prevent defects in subsequent production. At the same time, a face-to-back bending test was carried out to verify the bonding performance.
3. When bending operation is required for composite plates such as reels and stamping heads, the edges of the titanium composite plates should be peeled off cleanly. When the temperature is low, it should be heated to a certain temperature before bending to prevent edge cracking.
4. During beveling and pipe drilling operations, the blanking and drilling operations should be processed from the titanium layer to the steel layer as much as possible to prevent the composite board from being torn or cracked.
5. For micro-cracks on the surface of the composite board, the defects must be removed before repair welding. Direct repair welding can be used for small cracks.
6. For the non-fitting found in the inspection process, if the area is large, the material must be replaced. If the area is small, a remedy can be used, and the non-bonded area is reinforced with titanium screws. Process first before proceeding with subsequent operations

Application of nickel copper alloy in space

/in /by

As we all know, about 70% of the world’s nickel production is used in stainless steel production. Stainless steel was independently discovered by some researchers in 1912, but corrosion-resistant nickel base alloy was discovered earlier. In 1906, a nickel-copper (Ni Cu) alloy developed by inco was patented. The alloy has now developed into a group called Monel ® Two thirds of the nickel alloy is nickel and one-third is copper.

The strength of the nickel-copper alloy is higher than that of pure nickel, and it shows excellent corrosion resistance in a variety of non-oxidizing acid and alkaline environments (including rapidly flowing seawater). Nickel copper alloy can well withstand various concentrations of hydrofluoric acid in the temperature range up to the boiling point, and can withstand various forms of sulfuric acid and hydrochloric acid under reducing conditions.

characteristic

Nickel copper alloy also has excellent oxidation resistance (combustion resistance) in a high oxygen environment, and has excellent mechanical properties below zero and up to 550 ℃ (1020 ℉). Nickel copper alloys are easily made by hot working, cold working, machining, and welding. The most famous type of nickel-copper alloy is alloy 400 (n04400). Alloy 400 can only be hardened by cold work, but after the addition of aluminum and titanium in 1924, a higher strength age hardening product, K-500 (n05500), was produced. adopt γ For the deposition of phase particles, the yield strength reached 690 MPa (100 kilopounds per square inch), which was about three times higher than that of alloy 400 (n04400).

Space

Nickel copper alloys exist in pipes, bars, and wires for various space applications. The natural flame resistance of nickel-copper alloy in oxygen, its excellent properties at temperatures below zero, and the high strength of K-500 make this alloy an important material for the oxidizer side turbopump of oxygen-rich liquefied fuel rocket engines (such as blue origin be-4).

“Blue origin” uses three-dimensional additive manufacturing to manufacture many key components of ox booster pump (OBP). Its shell is a printed aluminum part, and all stages of the turbine are printed with K-500. Figure 1 shows the shell of the blue origin be-4ox booster pump. This manufacturing method can integrate complex internal flow channels into the shell, while it is much more difficult to manufacture this kind of shell by conventional methods. The nozzle and rotor of the hydraulic turbine are also made of three-dimensional printing, and the required fit can be achieved with only a small amount of machining.

Even today, nickel-copper alloys developed more than a century ago play a crucial role in high-demand frontier applications.

Application of titanium in new industrial fields

/in /by

Titanium alloy is a relatively young metal. It has a history of 60 or 70 years since it was developed. After entering the 20th century, traditional steel and aluminum can no longer meet the needs of aerospace, navigation, and other fields. In 1954 Titanium alloy materials were developed by American companies.

Titanium alloy is an alloy composed of titanium and other elements. Titanium alloy materials have the characteristics of lightweight, high strength, low elasticity, high-temperature resistance, and corrosion resistance. Titanium is also used, and there are many grades of titanium. Different industries will choose the appropriate grade of titanium according to their requirements. I believe that many people know this material because of a buzzword – “blind my titanium alloy eyes”! Many countries in the world have recognized the importance of titanium alloy materials, have successively carried out research and development on them, and have put them into practical applications. Let’s take a look at the application of titanium alloy in design. Lamborghini Lamborghini Aventador Estatura GXX uses a lot of carbon fiber and aviation-grade titanium alloy.

SP Engineering developed a complete set of the exhaust system and ECU improvements for the Ferrari 599, including a new catalytic converter and titanium alloy exhaust mid-tail section, and finally, the 6.0-liter V12 engine power was increased to 685 horsepower.

As Ducati’s flagship model, the 1199 Superleggera is equipped with a magnesium alloy unibody frame, magnesium alloy wheels, carbon fiber body panels, Brembo brakes, Akrapovic titanium exhaust, DWC head-up balance control system, DTC traction control system, EBC engine A series of high-tech auxiliary configurations such as braking system and DDA+ data analysis system.

Titanium “Devil” Motorcycle

3D printed titanium alloy bicycle frame Renishaw, the only metal additive manufacturing company in the UK, has teamed up with Empire Cycles, a British bicycle design, and manufacturer, to produce a 3D printed metal frame, using titanium alloy as the printing material. Thanks to topology optimization technology, the frame is not only stronger but also lighter, one-third lighter than normal materials. The shape can be adjusted at any time during the production of the frame, and it is more customizable and can be adjusted for each batch of products.

Most of the No.1 car designed by Paul Budnitz is made of titanium alloy, with a minimalist shape and lines, and there is no shortage of accessories, such as disc brakes, carbon fiber chain belts, quick-release devices, etc. Toys” famous designer.

3D Printed Titanium Headphones Japanese hi-fi company Final Audio Design (FAD) has partnered with NTT Data Engineering Systems and Probox Japan to design and manufacture the world’s first mass-produced 3D printed titanium headphones, dubbed ” Final Audio Design LAB 01″. Its casing was printed by NTT using an EOSINT M 280 3D printer from Germany’s EOS, a selective laser sintering (SLS) system for metal parts, made from titanium alloy Ti64 powder.

ID Mouse ID Mouse was designed by Intelligent-design in the Netherlands. The surface is made of titanium alloy, the metal wire drawing treatment is nobler, and the resin material is added. It is also worth mentioning that the mouse wheel uses the metal neodymium (Neodymium) that we are not familiar with. The material of “King of Permanent Magnet” is used in electronic machinery and other industries with excellent performance. There are also black and white options on the side of the mouse, which are simple and simple.

Titanium alloy straw, pure titanium alloy portable straw from Hong Kong cool geek. This straw can not only be used to suck drinks but can also be inserted directly into the fruit to drink juice. The straw also comes with a straw brush for easy cleaning.

Tool ring, made of titanium alloy, you can think of it as a Swiss army knife in a ring – the top of the ring hides four small tools inside, namely a bottle opener, a knife, a saw, and a small comb.

Jordan’s 22nd generation sneakers, its exposed interchangeable bearing posts can accommodate two cushioning systems. A reinforced titanium alloy shoe bone support plate provides support for the midfoot and arch of the foot. The design of this sneaker was inspired by the F-22 fighter jet.

Titanium alloy sci-fi music box, the whole body is constructed of titanium alloy, with a very sci-fi design. Three different kinds of music can be played on the left and right sides, the left is the “Star Wars” theme song, the episode from “The Empire Strikes Back” and the “Star Trek” theme; the right tune is Pink Floyd’s “Another Brick” in the Wall”, “Smoke on the Water” by Deep Purple’s and “Imagine” by John Lennon, limited to 66 pieces worldwide.

Titanium wine pitcher, from Japanese outdoor gear manufacturer Xuefeng, with an iconic minimalist design. The capacity of the jug is not large, but it is insulated from heat and cold due to the texture of titanium alloy, and it is resistant to corrosion. Whether in the city, the forest, or the fierce wasteland, taking a sip will make you more aware of the importance of preserving one’s personal space.

Coins with titanium, Tristan da Cunha with small pieces of Concorde titanium. The coin was minted in 2009 to commemorate the 40th anniversary of the Concorde’s maiden flight. The coins are gold plated and each side contains a small piece of titanium taken from a Concorde, collect all the coins and you can build a miniature Concorde.

Cardiac stents, which first appeared in the 1980s, have gone through the development of metal stents, coated stents, and soluble stents. The main materials are stainless steel, nickel-titanium alloy, or cobalt-chromium alloy.

Tips for purchasing 304 stainless steel water pipes

/in /by

304 stainless steel water pipe is a long strip of steel with a hollow section and no joints around it. The steel pipe has a hollow section and is widely used as a pipeline for transporting fluids, such as pipelines for transporting oil, gas, water, and certain solid materials. When purchasing 304 stainless steel water pipes, pay attention to the following aspects:
To purchase 304 stainless steel water pipes, first look at the other party’s three certificates. Business license, organization code certificate. Those with a business license below 5 million are basically either marketing or small workshops. other relevant qualifications. Especially the special equipment manufacturing production license! With this, it is a qualified enterprise.
Looking at the performance of customers, especially those who have cooperated with the supply of large petrochemical enterprises, shows that the production capacity and quality are acceptable. A lot of performances will be messed up, so you can look at the other party’s contract if the performance is similar to your purchase purpose, if the other party can give it to you within half an hour, it is true. Through the introduction and description of suppliers in various industries in the market. In particular, the pertinent evaluation of the manufacturer by the dealer market customers has a great reference effect.
If it is a large number of purchases, you need to go to the field to inspect the other party’s workshop, production equipment, factory area, warehouse, testing methods, and equipment.
The above is the basic preparation work you need to do to use stainless steel water pipes. I hope everyone can purchase 304 stainless steel water pipes that meet the standards.