product picture

Orders from Australian customers

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We received the customer’s Round Bar copper-nickel (90/10) inquiry in September, and the agreed delivery time is 20 days. Overall, everything is going according to plan.

Unfortunately, the quantity requested by the customer is only 1 of each size. The customer is a careful person and requires samples to be sent first, and the order will be placed after the sample is passed the test. The sample passed the test and passed the test. In October, we were honored to receive the official order from the customer, and the goods were shipped in November. In December, we received the customer’s second order and shipped it.

It is my pleasure to share the specifications and photos of the goods with you:

product order

product diplay

We are very pleased to be able to connect 2 orders! We sincerely thank our customers for their strong support. I hope our future cooperation will be closer. We will wholeheartedly provide you with the most cost-effective product
If you need Round Bar copper-nickel (90/10), Cu90Ni10 Solid Bar, welcome to inquire, we will serve you wholeheartedly! Email: [email protected]

 

space station

NASA astronauts unfurl 4th roll-out solar array on spacewalk outside space station

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Only two more new solar arrays are to be installed after a successful spacewalk.

The International Space Station (ISS) has a fourth new solar array thanks to the work of two NASA astronauts on a seven-hour spacewalk.

Frank Rubio and Josh Cassada, both flight engineers on the space station’s Expedition 68 crew, again ventured outside of the orbiting complex on Thursday (Dec. 22) to install a new ISS Roll-Out Solar Array (iROSA) to augment the station’s power supply. The spacewalk was a near repeat of the extravehicular activity (EVA) that Rubio and Cassada performed almost three weeks ago, but this time focused solely on a power channel located on the station’s port-side truss.

The two astronauts also reversed roles, with Rubio serving as the lead spacewalker (EV-1) for Thursday’s outing. Rubio and Cassada began the spacewalk at 8:19 a.m. EST (1319 GMT), exiting the U.S. Quest airlock and quickly getting to work on their first assigned tasks. As Cassada set up a foot restraint at the end of the station’s Canadarm2 robotic arm, Rubio configured the cables that they would later connect to tie the new array into the station’s 4A power channel.

space station

NASA astronaut Frank Rubio (in the foreground) transitions along the space station as fellow NASA astronaut and Expedition 68 crewmate Josh Cassada moves an International Space Station (ISS) Roll-Out Solar Array (iROSA) on the end of the Canadarm2 robotic arm during a spacewalk on Thursday, Dec. 22, 2022. (Image credit: NASA TV)

The two astronauts then worked together to free the iROSA from the platform on which it was launched and temporarily stowed on the station. Like the array that was installed on Dec. 3, the 4A iROSA was delivered to orbit by a SpaceX CRS-26 Dragon cargo spacecraft, which arrived at the ISS on Nov. 27.

After Rubio freed the last bolt holding the array in place, Cassada, now positioned at the end of the robotic arm, took hold of the assembly to carry it to its installation site. At the controls of the Canadarm2 was NASA astronaut Nicole Mann, with Koichi Wakata of the Japan Aerospace Exploration Agency (JAXA) coordinating her actions with Cassada outside.

“Just a head’s, Koichi,” radioed Cassada during a break between moves, “that last one stopped a little quickly on me. If you see it ramping up on the next one, can you give me a heads-up? That would be awesome.” Although weightless in the microgravity environment of space, the mass of the 750-pound (340-kg) still had significant inertia when being moved.

RELATED STORIES:
— The most memorable spacewalks in history

— The International Space Station: Facts, history, and tracking

— In photos: The amazing spacewalks of Expedition 61

Rubio transitioned along the truss to meet Cassada at the P4 site. The two spacewalkers then unfolded the iROSA from its launch configuration and then secured the array atop a mounting bracket installed on an earlier EVA. Using a power tool specifically designed for astronauts to use on spacewalks, Rubio tightened the four bolts on the right and left sides of the iROSA to hold the assembly open.

After waiting for the space station to be in “eclipse,” or when it was in the shadow of Earth, such that the existing solar array wings were not producing electricity, Rubio and Cassada then integrated the iROSA into the 4A power channel by attaching cables connecting the new array to the station.

A new International Space Station (ISS) Roll-Out Solar Array (iROSA) unfurls in front of the legacy 4A solar array wing, augmenting the power for the orbiting complex. (Image credit: NASA TV)

At that point, all that was left to do was let the iROSA unfurl. With the release of two bolts, the potential energy stored by the rolled-up carbon composite booms caused the array to unroll on its own to its full 63-foot (19-meter) length with no motor needed.

“We can finally run that microwave we’ve wanted to run,” said Cassada, joking about the extra power from the new array.

The whole process took about 10 minutes. Cassada tightened two bolts to stiffen the array and its installation was complete.

The ISS Roll-Out Solar Arrays are being installed in front of, and partially overlaying, slightly-degraded, existing solar panel wings. When used in tandem and once all six iROSAs are in place, the upgraded power system will increase the space station’s electricity supply by 20 to 30 percent.

Cassada and Rubio completed the spacewalk by cleaning up and taking inventory of their tools before reentering the airlock at 3:27 p.m. EST (2027 GMT), seven hours and eight minutes after they began the EVA.

Thursday’s excursion had been scheduled for Wednesday but was delayed a day because the space station needed to be maneuvered away from an approaching piece of Russian rocket debris. It was the third spacewalk for both Rubio and Cassada. They now have logged 21 hours and 24 minutes working the vacuum of space.

The EVA was the 12th for the year, the fourth for Expedition 68, and the 257th since 1998 in support of the assembly and maintenance of the ISS.

Corrosion patterns of stainless steel in industrial water systems

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1. Corrosion of cooling water to the stainless steel heat exchanger

Chromium-nickel steel, especially 18Cr-8Ni austenitic stainless steel, is most widely used in the chemical industry due to its high stability in many chemical media and its ability to resist high-temperature gas corrosion. Although stainless steel has a very low overall corrosion rate in various industrial waters, under actual industrial production conditions, accidents of corrosion damage to stainless steel equipment, especially various industrial water coolers, are very frequent.

In industrial water, the pitting corrosion and stress corrosion cracking of stainless steel is caused by chloride ions in the water, so people often hope to find out the critical chloride ion concentration that causes stress corrosion cracking, but due to the factors that cause localized corrosion of stainless steel in the actual operating device It is difficult to determine, so it is often found that the life of two equipment with roughly the same conditions is very different; the same stainless steel has stress corrosion cracking in cooling water with a low concentration of chloride ions (only 10~20mg/L). However, it is safe to use for a long time in seawater with a high concentration of chloride ions. Although the mechanism of stress corrosion cracking has not been fully understood so far, and the boundary conditions for completely avoiding or eliminating stress corrosion cracking cannot be proposed, the statistical analysis of the operation of a large number of industrial equipment and many in-depth laboratory studies have enabled people to understand To the main factors affecting stainless steel pitting corrosion and stress corrosion cracking, put forward some statistical laws, these works are very beneficial to prolong the operating life of stainless steel equipment.

The corrosion resistance of stainless steel often depends on the oxide film existing on the metal surface, and the oxide film can only be formed when there is oxygen, oxidant, or anodic polarization. Once the necessary oxidation conditions are lost, the oxide film will be destroyed, such as in crevices and under deposits. Such damage conditions may occur. In water with fully dissolved oxygen, as long as the water flow rate is not lower than 1.5m/s, no deposits will appear on the surface of the stainless steel, and the integrity of the oxide film can be maintained. Under the actual operating conditions of industrial water, the water flow rate is often lower than 1.5m/s, various solid particles will deposit, microorganisms in the water will cause dirt, and sometimes there will be gaps in the equipment structure, especially in the water. Aggressive chloride ions, result in pitting corrosion and even stress corrosion cracking. Of course, there must be tensile stress in order to produce stress corrosion cracking. In addition, pitting corrosion and stress corrosion cracking are related to chloride concentration, pH value, oxygen concentration, temperature, stress level, cation, and other factors, but the degree of dependence is different.

2. Pitting corrosion and crevice corrosion of stainless steel

Stainless steels immersed in chloride-containing aqueous solutions are prone to pitting and crevice corrosion. When the stainless steel is above the critical pitting potential in the corrosive medium, the active area will be polarized by the anode current due to the existence of a passivation-activation battery, which will intensify the development of pitting corrosion. Once pitting is induced and developed, the chloride ions in the pits will autocatalyze concentration (enrichment). Numerous studies have revealed that the pH value and chloride ion concentration of the solution where pitting and crevice corrosion occur are completely different from the bulk solution. The pH value at the place of occurrence is significantly lowered, and the concentration of chloride ions is highly concentrated. There are literatures that use artificial corrosion pits to study the corrosion of 304L, 316L, and 18Cr15Ni5Mo (at 70°C, 0.5mol/L, NaCl solution), the measurement results of the composition and pH value of the solution in the hole are shown in the table below.

stainless steel material

The concentration of original chloride ions in raw water or circulating water does not have decisive significance on whether pitting corrosion occurs in stainless steel. In the system where pitting occurs, the test results of chloride ions in the pits prove that the concentration of chloride ions is amazing. For example, the cooling water of a factory contains only 50mg/L of Cl-, but the concentration of Cl- in the corrosion pit is as high as 104mg/L. Usually, the Cl-concentration in the corrosion pit is several thousand mg/L, and the CI-concentration in the artificial crevice can reach 105mg/L. This fact also exists in production practice. 1Cr18Nil0Ti steel has pitting corrosion in tap water containing 196mg/L of chloride ions and in river water with low chloride ion concentration, and pitting corrosion occurs under sediments. Once steps are taken to remove the deposit or rust, the problem is avoided. As another example, in a water system with low chloride ion content, austenitic stainless steel was also damaged, and a high concentration of chloride deposition was found at the damaged site. These facts show that despite the large difference in the Cl-concentration of the system, as long as there is sediment, it will eventually produce the same bad results. Although the increase of CI- concentration will negatively shift the pitting corrosion potential of stainless steel, the effect is not obvious under the conditions of normal temperature and low Cl- concentration (<10< span=””>3mg/L).

3. Stress corrosion cracking of stainless steel

In industrial water, the stress corrosion cracking of austenitic stainless steel is induced by pitting corrosion. The influencing parameters of the two are the same, but the critical values required by each are different. As for the effect of stress when stress corrosion cracking occurs, the 18-8 austenitic stainless steel was studied in 0.05mol/L NaCI with the specimen in the occluded area under tension, and it was found that when the specimen was anodically polarized (oV, SCE), The crack is the active area, the tensile stress promotes the rupture of the passivation film, and makes it difficult to repair the film. As a result, the potential here becomes more negative, the pH value drops faster, and the corrosion is more serious.

4. Intergranular corrosion of stainless steel

In most cases, intergranular corrosion of austenitic stainless steels is caused by chromium-depleted regions adjacent to grain boundaries. Stainless steel must have a certain amount of chromium. If the chromium content decreases, its corrosion resistance will deteriorate. When the carbon content is ≥0.02%, in the temperature range of 510~788°C, chromium carbide Cr23C8 or carbon will precipitate at the grain boundary. In this way, chromium will be separated from the solid solution in the form of chromium carbide, which will reduce the chromium content near the grain boundary and form a chromium-depleted area. The chromium-depleted area adjacent to the grain boundary corrodes due to poor corrosion resistance. 18-8 stainless steel (type 304) generally contains 0.06% to 0.08% carbon, and there is enough carbon and chromium to form chromium carbide precipitation to form a chromium-depleted area between the grains, as shown in the figure below. Weld corrosion is a special intergranular corrosion of stainless steel. The weld corrosion zone is usually on a strip (heat-affected zone) slightly away from the weld on the base plate, and this part of the stainless steel has been heated in the sensitizing temperature range during the welding process.

UNS N09925 Nickel-base Alloy Bar Strength Composition

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UNS N09925 alloy is an age-hardenable nickel-iron-chromium alloy. On the basis of nickel-iron-chromium, molybdenum and copper elements are added to strengthen the alloy, which improves the strength and corrosion resistance of the material. The specific chemical composition is as follows. UNS N09925 nickel content is sufficient to prevent chloride ion stress corrosion cracking, molybdenum and copper are added to provide good reduction resistance properties to the alloy, molybdenum helps resistance to pitting and crevice corrosion, and chromium content provides sufficient oxidation resistance.

UNS N09925 Nickel-base Alloy

UNS N09925 corresponding grades: 0Cr22Ni42Mo3Cu2Ti2AlNb, Incoloy925, Alloy925, Nicrofer4320Ti, W.Nr.2.4852

Chemical composition of UNS N09925:

C: ≤0.03

Si: ≤0.5

Mn: ≤1.0

P: ≤0.03

S: ≤0.03

Mo: 2.5-3.5

Ni: 42.0-46.0

Cr: 19.5-23.5

Cu: 1.5-3.0

Fe: margin

UNS N09925 physical properties:

Density: 8.14g/cm3

Melting point: 1343°C

UNS N09925 is a high-temperature and corrosion-resistant nickel-based alloy, which has the ability to resist sulfide stress cracking and stress corrosion cracking in sour crude oil and natural gas, and also has the ability to resist oxidation, hydrogen bubble corrosion, crevice corrosion, and intergranular corrosion specialty. It is mainly used in corrosion-resistant environments such as oil, natural gas, and marine industries. It is suitable for ship fasteners and pipelines, etc., and has high thermal strength.

What should the laser pipe cutting machine pay attention to when cutting copper pipes?

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What factors affect the cutting speed and quality when the laser tube cutting machine cuts copper tubes? When piercing and cutting copper, high-pressure oxygen is used to improve the reliability of the process. But for brass, nitrogen is actually better, and the cutting effect will be better. The laser of the round pipe-cutting machine can reduce the time that the material is in a reflective state, and improve the perforation speed and cutting efficiency.

The focus position of the pipe-cutting machine is also important when cutting copper tubes, and should be set close to the top surface, which minimizes the surface material that interacts with the beam at the beginning of the process, thereby maximizing the power density of the beam and making the material more compact. Melts fast. The tail material of the pipe-cutting machine is shorter, which saves material costs to a greater extent.

How much is 2205 duplex stainless steel per ton？

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How much is a ton of 2205 duplex stainless steel? This question is a question that arises from many people who do not know about duplex stainless steel. 2205 duplex stainless steel is a stainless steel in which the ferrite phase and austenite phase coexist, and it is also a steel grade that combines excellent corrosion resistance, high strength, and easy processing and manufacturing.

Since the price of stainless steel is affected by many factors, let’s first look at how the price of 2205 stainless steel is affected.

1. Economic cycle

The iron and steel industry is the basic industry of the national economy. The cyclical fluctuation of the national economy is an objective economic law, and the iron and steel industry is one of the industries most closely related to the economic cycle. It can be said that the stainless steel market fluctuates with macroeconomic fluctuations.

2. Raw material cost

The price of stainless steel products has a strong correlation with the price of raw materials (mainly nickel and chromium), and 2205 duplex stainless steel prices fluctuate with changes in raw material prices. Nickel is mainly used in stainless steel production, and its consumption is mainly driven by stainless steel production. The dramatic increase in stainless steel production has boosted nickel consumption in recent years.

3. Market supply and demand

Against the background of a sharp increase in stainless steel production in Asia, the current stainless steel market has begun to show signs of relative excess supply, which has put pressure on stainless steel prices. With the development of the economy and the improvement of living standards, as well as the requirements for the appearance and service life of steel, the application of stainless steel will become more and more extensive. In the long run, stainless steel demand growth will support stainless steel prices.

4. Technological innovation

The impact of technological innovation on the international stainless steel market includes: first, scientific and technological progress will improve the function and performance of products to a certain extent, broaden the application fields of stainless steel, stimulate market demand for stainless steel products, and increase market prices; The impact can increase labor productivity, improve the structure of stainless steel production, and reduce the global supply price of stainless steel; third, scientific and technological progress may lead to the emergence of new alternative materials, thereby reducing the demand for stainless steel and reducing its market price, but at present, it can be completely New metal materials to replace stainless steel have not yet appeared. Therefore, the impact of technological innovation on the stainless steel market is currently difficult to assess.

5. Economic policy

Changes in national macroeconomic policies, monetary policies, foreign exchange policies, and import and export policies, such as the introduction of policies to promote consumption upgrades, will stimulate the demand for stainless steel final products, or some countries will impose trade barriers on some stainless steel products. These factors also have a certain impact on the price of stainless steel.

It is not difficult to see from the above that there are many factors that affect the price of 2205 duplex stainless steel. Generally speaking, the price of 2205 duplex steel is not fixed. Linkun Alloy is a professional wholesale and processing enterprise of duplex steel materials. You can leave a message or call for consultation The latest price of 2205 duplex stainless steel.

Suggest to collect eight items of stainless steel welding and pay attention to nine problems

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Share some of the eight precautions for stainless steel welding, let’s take a look!

1. Chrome stainless steel has certain corrosion resistance (oxidizing acid, organic acid, cavitation), heat resistance, and wear resistance. It is usually used for power plants, the chemical industry, petroleum, and other equipment and materials. The weldability of chrome stainless steel is poor, so attention should be paid to the welding process, heat treatment conditions, etc.

2. Chromium 13 stainless steel has high hardenability after welding and is easy to crack. If the same type of chromium stainless steel electrodes (G202, G207) are used for welding, preheating above 300 ℃ and slow cooling treatment at about 700 ℃ after welding must be carried out. If the weldment cannot undergo post-weld heat treatment, chromium-nickel stainless steel electrodes (A107, A207) shall be used.

3. In order to improve the corrosion resistance and weldability of chrome 17 stainless steel, appropriate stability elements such as Ti, Nb, and Mo are added, and the weldability is better than that of chrome 13 stainless steel. When the same type of chromium stainless steel electrodes (G302, G307) is used, the preheating above 200 ℃ and the tempering after welding at about 800 ℃ shall be carried out. If the weldment cannot be heat treated, chromium-nickel stainless steel electrodes (A107, A207) shall be used.

4. During the welding of chromium-nickel stainless steel, carbides are precipitated by repeated heating, reducing corrosion resistance and mechanical properties.

5. Chromium nickel stainless steel electrode has good corrosion resistance and oxidation resistance and is widely used in the chemical industry, fertilizer, petroleum, and medical machinery manufacturing.

6. Chromium nickel stainless steel coating includes titanium calcium type and low hydrogen type. Titanium calcium type can be used for AC and DC welding, but the penetration is shallow during AC welding, and it is easy to redden, so DC power supply should be used as far as possible. Diameters 4.0 and below can be used for all position weldments, and 5.0 and above can be used for flat welding and flat fillet welding.

7. The welding rod shall be kept dry during use. The titanium calcium type shall be dried at 150 ℃ for 1 hour, and the low hydrogen type shall be dried at 200-250 ℃ for 1 hour (repeated drying is not allowed, otherwise the coating is easy to crack and flake) to prevent the coating of the welding rod from sticking oil and other dirt, so as not to increase the carbon content of the weld and affect the quality of the weldment.

8. In order to prevent eye corrosion due to heating, the welding current should not be too large, about 20% less than that of carbon steel electrode, the arc should not be too long, and the interlayer should be cooled quickly, so it is better to narrow the weld bead.

9 major problems in stainless steel welding

1. What are stainless steel and stainless acid-resistant steel?

Answer: The content of the main added element “chromium” in the metal materials (nickel, molybdenum and other elements that need to be added) can make the steel in the passivation state and stainless steel. Acid-resistant steel refers to steel that is resistant to corrosion in strongly corrosive media such as acid, alkali, and salt.

2. What is austenitic stainless steel? What are the commonly used brands?

Answer: Austenitic stainless steel is the most widely used and has the most varieties. For example:

18-8 series: 0Cr19Ni9 (304) 0Cr18Ni8 (308)

18-12 series: 00Cr18Ni12Mo2Ti (316L)

25-13 series: 0Cr25Ni13 (309)

＜ 4 ＞ 25-20 series: 0Cr25Ni20, etc

3. Why is it difficult to weld stainless steel?

Answer: The main process difficulties are:

The stainless steel material has a strong thermal sensitivity, staying at 450-850 ℃ for a long time, and the corrosion resistance of the weld and heat-affected zone is seriously reduced.

Hot cracks are easy to occur.

Poor protection and severe high-temperature oxidation.

The linear expansion coefficient is large, resulting in large welding deformation.

4. Why should effective process measures be taken for welding austenitic stainless steel?

Answer: General process measures include:

Welding materials shall be strictly selected according to the chemical composition of the base metal.

＜ 2 ＞ Low current, Rapid welding; Small wire energy, reduce heat input.

The welding wire and electrode with a fine diameter shall not swing and shall be welded in multiple layers and passes.

＜ 4 ＞ The weld and heat-affected zone are forced to cool, reducing the residence time of 450-850 ℃.

＜ 5 ＞ Argon protection at the back of the TIG weld.

The weld in contact with the corrosive medium shall be welded finally.

(7) Passivation treatment of weld and heat affected zone.

5. Why should 25-13 series welding wires and electrodes be used for welding austenitic stainless steel, carbon steel, and low alloy steel (dissimilar steel welding)?

Answer: For welding dissimilar steel welded joints between austenitic stainless steel and carbon steel, low-alloy steel, 25-13 series welding wires (309, 309L) and welding rods (A312, A307, etc.) must be used as weld deposit metal. If other stainless steel welding materials are used, the martensite structure will be generated on the fusion line of one side of carbon steel and low alloy steel, which will cause cold cracks.

6. Why should 98% Ar+2% O2 shielding gas be used for solid stainless steel welding wire?

Answer: If pure argon gas is used for MIG welding with the solid stainless steel welding wire, the surface tension of the molten pool is large, and the weld formation is poor, showing a “hunchback” weld shape. Add 1-2% oxygen to reduce the surface tension of the molten pool and make the weld formation smooth and beautiful.

7. Why is the surface of the MIG weld of solid stainless steel welding wire blackened?

Answer: The MIG welding speed of solid stainless steel welding wire is fast (30-60cm/min). The shielding gas nozzle has run to the front end molten pool area. The weld is still in a hot and hot state. The weld is oxidized by air, and the surface generates oxides. The weld is blackened. Acid pickling and passivation can remove the black skin and restore the original surface color of stainless steel.

8. Why does the solid stainless steel welding wire need a pulsed power supply to achieve jet transfer and splash-free welding?

Answer: During MIG welding with the solid stainless steel welding wire, φ 1.2 Welding wire, when the current I ≥ 260-280A, the jet transfer can be realized; If the value is less than this value, the droplet is short-circuited, with a large spatter, and generally cannot be used. Only when the MIG power supply with a pulse is used and the pulse current is greater than 300A, the pulsed droplet transfer under 80-260A welding current can be realized without spatter welding.

9. Why is the flux-cored stainless steel wire protected by CO2 gas? No pulsed power supply?

Answer: For the commonly used flux-cored stainless steel welding wires (such as 308, 309, etc.), the flux formula in the welding wire is developed according to the chemical and metallurgical reaction of welding under CO2 gas protection, so it cannot be used for MAG or MIG welding; The pulsed arc welding power source shall not be used.

Titanium rod manufacturers introduce methods to identify fake and inferior products!

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Many titanium rod manufacturers want to buy high-quality titanium rods when they buy titanium rods, but how to distinguish the quality of titanium rods? titanium rod manufacturers teach us how to make titanium rods good or bad from many aspects and angles.

1. The appearance of counterfeit and inferior titanium rods often has pockmarks.

The pockmarked surface is due to the serious wear and tear of the rolling groove, which leads to the irregular and uneven surface of the titanium material. Because manufacturers of counterfeit and inferior titanium rods seek to make profits, there are often overruns in grooving and rolling.

2. False and inferior titanium rods are easy to scratch. The reason is that the manufacturers of fake and inferior titanium rods have poor equipment, which is prone to burrs and scratches on the surface of titanium materials. Deep scratches reduce the strength of titanium.

3. The horizontal ribs of fake and inferior titanium rods are thin and low, and often appear to be full and dissatisfied. The reason is that in order to achieve a large negative tolerance, the reduction in the first few passes of the finished product is too large, the iron shape is too small, and the hole shape is not full.

4. False and inferior titanium rods are prone to folding.

Folding is a variety of fold lines formed on the surface of titanium rods, and this defect often runs through the longitudinal direction of the entire product. The reason for the folding is that the counterfeit and inferior manufacturers pursue high efficiency, and the reduction is too large, resulting in ears. Folding occurs during the next rolling process. The folded product will crack after bending, and the strength of the titanium material will be greatly reduced.

5. Fake and inferior titanium rods are prone to scarring on the surface.

There are two reasons: (1) The raw materials of fake and inferior titanium rods are uneven and have many impurities. (2) The guides and guards of fake and inferior material manufacturers are poorly equipped and easily stick to titanium. These impurities are prone to scarring after biting the roll.

6. Cracks are easy to occur on the surface of fake and inferior materials. The reason is that the billet is adobe, and the adobe has many pores. During the cooling process, the adobe suffers from thermal stress, cracks occur, and there are cracks after rolling.

7. False and inferior titanium rods have no metallic luster and are light red or similar in color to pig iron. There are two reasons for this. Two, its blank is adobe. The rolling temperature of fake and inferior materials is not standardized, and their titanium temperature is measured visually, so they cannot be rolled according to the regular austenite region, and the function of titanium materials is naturally unqualified.

8. The cross-section of fake and inferior titanium rods is elliptical. The reason is that in order to save materials, the reduction amount of the first two passes of the finished roll is too large. specification.

The above is all the content shared by the titanium rod manufacturer, I hope you can like it, welcome your consultation!

What are the methods to prevent stainless steel solid round rods from rusting?

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From the product name, it seems that stainless steel will not rust, but it is not. We need to know the specific methods to avoid rust from stainless steel products. In fact, this has a lot to do with the nickel element in stainless steel solid round rods. The following and The editor of the same metal will look at a few key points to avoid stainless steel rusting, for your reference only.

1. In polluted air (such as an atmosphere containing a large amount of sulfide, carbon oxide, and nitrogen oxide), when it encounters condensed water, it will form sulfuric acid, nitric acid, and acetic acid liquid points, causing chemical corrosion.

2. Organic juices (such as vegetables, noodle soup, sputum, etc.) adhere to the surface of stainless steel screws. In the presence of water and oxygen, organic acids are formed, and organic acids will corrode the metal surface for a long time.

3. The attachment of dust or heterogeneous metal particles, in the humid air, the attachment and the condensed water of the stainless steel screw connect the two into a micro-battery, which triggers an electrochemical reaction and destroys the protective film, which is called electricity. chemical corrosion.

4. The surface of the stainless steel bar adheres to acid, alkali, and salt substances (such as alkaline water and lime water splashed on the wall for decoration), causing local corrosion.

Main characteristics and uses of aluminum brass

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Special brass is formed by adding aluminum, silicon, manganese, lead, tin, and other elements into a copper-zinc alloy. Such as lead brass, tin brass, aluminum brass, silicon brass, manganese brass, etc.

Lead brass has excellent cutting performance and good wear resistance and is widely used to make clock parts, bearing shells, and bushes by casting.

Tin brass has good corrosion resistance and is widely used in the manufacture of marine parts.

Aluminum in aluminum brass can improve the strength and hardness of brass, and improve the corrosion resistance in the atmosphere. Aluminum brass is used to make corrosion-resistant parts.

Silicon in silicon brass can improve the mechanical properties, wear resistance, and corrosion resistance of copper. Silicon brass is mainly used to make parts for seagoing ships and chemical machinery.

What are the main characteristics of aluminum brass?

Aluminum brass has strong wear resistance. It has high strength, high hardness, and strong chemical corrosion resistance. There are also outstanding mechanical properties of cutting. Seamless copper tube drawn from aluminum brass is soft and wear-resistant. Aluminum brass seamless tubes can be used for heat exchangers and condensers, cryogenic pipelines, and submarine transport tubes. Manufacture sheet, bar, pipe, casting parts, etc. It contains 62%~68% copper and has strong plasticity. It is used to manufacture pressure-resistant equipment.

What are the uses of aluminum brass?

Aluminum in aluminum brass can improve the strength and hardness of brass, and improve the corrosion resistance in the atmosphere. Aluminum brass is used to make corrosion-resistant parts.

What are the components of aluminum brass?

Copper: 66.0 ～ 68.0

Sn: ≤ 0.2

Zinc: allowance

Lead Pb: ≤ 0.5

Phosphorus P: ≤ 0.02

Aluminum: 2.0 ～ 3.0

Fe: ≤ 0.6

Manganese Mn: ≤ 0.5

Antimony Sb: ≤ 0.05

Note: ≤ 1.5 (impurities)

What are the applications of aluminum brass?

The main alloy composition of aluminum brass is Cu Zn Al. In order to improve the strength, corrosion resistance, wear resistance, etc. of aluminum brass in practical application, elements such as As, Mn, Fe, Ni, etc. are often added to the alloy, thus greatly improving the comprehensive properties of the material. Due to the aluminum zinc equivalent coefficient 6 β The phase trend is large, and the strengthening effect is good. When the aluminum content increases γ Phase. Although the hardness of the alloy is increased, the plasticity is sharply reduced. In aluminum brass, the ionization tendency of the aluminum surface is greater than that of zinc. The dense and hard aluminum oxide film is preferentially formed to prevent the alloy from further oxidation and improve the corrosion resistance to gas, and solution, especially high-speed seawater.