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Everyone all over the world is facing a difficult time right now because of the spreading virus. And MASK becomes everyone’s necessity. Even our company is for the steel material business, even we could not help to produce the mask. But we are doing our best to produce the mould parts which is used on mask-producing machine. This mould part is made by the 4140 plate in 41mm and 45mm thickness.

Now 4140 plate is our company hot selling items, our company makes the finished products by using our stock 4140 plate material. And the workers in our factory work over time every day for rushing on this. Hope it is very helpful for supporting the Mask-producing mill.

And about one month ago, China was going through the extremly difficult time owning to the virus was rampaging in Wuhan and Hubei Province. I was really touched when I hearing the news report about most of the people did their best to help and support that heavy area. I could see such strong team-working power very impressively.

Everyone was doing their best to fight with this virus war together. Someone from overseas bought many masks to deliver it to China. Some people even are poor but they donated the only money to Wuhan and Hubei people. The doctors and nurses were working date and night. No matter how exhausted and dangerous it is. And at the New Year’s Eve, most of the common workers went to Wuhan for building the temporary hospitals very rapidly. More and more doctors and nurses from different provinces help to support the different cities in Hubei. For reducing the wastage on the protective suit, they even did not drink the water as possible. They put a diaper on themselves for avoiding taking off and wasting the suit. We are moved because of such lovely people, we are lucky to have such brave people to protect us.

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1.2311 Sheet Plate is a German Die steel, the steel by “super clean” production process, pre hardened, showing the height of micro pure and excellent homogeneous structure, excellent polishing and light etching engraving. After heat treatment, processing and polishing performance is good, can be carried out, and can be processed, suitable for the surface treatment of chrome, material hardness even (to 400mm thick), good toughness, good mechanical processing performance. Gold microstructure is martensite and bainite structure.

Main be applied to in zinc, aluminum, magnesium and its alloy die-casting mould ; Hot-pressing mold, all kinds of hot forging die; Metal extrusion die, die set.

1.2311 Sheet Plate perfect for mould use . OTAI SPECIAL STEEL is Din 1.2311 steel stockholders and suppliers from china. we have more than 16 years experience in 1.2311 special steel and plastic mould steel supply.

1.2311 tool steel is a mould materials for plastic injection, it belong to the high quality medium carbon,Pre-hardness(28~34HRc), Cold work plastic mould steel. It no need further heat treatment. so you don’t have any worry about distortion or cracking. 1.2311 steel is most widely used to plastic mold material in injection plastic mould.

1.2311 tool steel round bar and flat sections can be cut to your required sizes. 1.2311 tool steel ground bar can also be supplied, providing a high quality tool steel precision ground tool steel bar to your required tolerances. 1.2311 tool steel is also available as Ground Flat Stock / Gauge Plate, in standard and nonstandard sizes.

Chemical composition of 1.2311 plastic mold steel plate

DIN 1.2311 tool steel, we can supply the round bar, flat bar, plate, hexagonal and square block. Diameters can be sawn to your required lengths as one offs or multiple cut pieces. Rectangular pieces can be sawn from flat bar or plate to your specific sizes. Ground tool steel bar and precision ground steel plate can be supplied, providing a quality precision finished bar to tight tolerances.

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Email: jack@otaisteel.com

42CrMo4 Sheet Plate for Mould on FaceMask Machine . OTAI Special steel provide any size of 42CrMo4 raw material use for mold on Mask Machine . As the coronavirus infection all over the world , and we need facemask to protect ourselves . And we need more Mask machine to produce more facemask . China as the One of the global manufacturing powers . We have an obligation to help fight the epidemic globally .

42CrMo4 Sheet Plate for Mould on FaceMask Machine .

42CrMo4 Alloy steel material stockholders and suppliers from China-OTAI SPECIAL STEEL . We have more 16 years experience in 42CrMo4 steel plate, round bar, flat bar, square bar supply . 42CrMo4 alloy steel is chromium, molybdenum, manganese containing low alloy steel . It has high fatigue strength, abrasion and impact resistance, toughness, and torsional strength. The following datasheet gives an overview of 42CrMo4 alloy steel.

42CrMo4 alloy steel material is a high quality Quenched and Tempered Alloy Structural steel . It belongs to the high quality medium carbon alloy steel, Oil Quenched & Tempered Hardenss is 28-34 HRC. 42CrMo4 Annealing delivery hardenss less than 250HB . 42CrMo4 raw materials is Perfect for mold making . 42CrMo4 Sheet Plate for Mould on FaceMask Machine for  Mask Production .

42CrMo4 sheet plate equivalent material

• ♦JAPAN♦ : JIS SCM440 alloy steel
• ♦GERMANY♦ : DIN WN-r 1.7255 / 42CrMo4 steel alloy
• ♦USA♦ :  AISI4140
• ♦BRITISH♦ : BS 708M40

3. 42CrMo4 alloy steel Chemical composition

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4140 steel provider OTAI shares the steel news with you.

Nowadays, we can find the pandemic affect every aspect of society .however, as a member of 4140 steel provider OTAI company, I ‘d like to talk about what influence it causes to the steel industry.

4140 steel provider-OTAI, supplies a wide range of steel products. including high-speed tool steel, cold works tool steel, hot works tools steel, plastic mold steel, engineering steel and machine structural steel, etc. After almost 20 years of development and growth, Otai Steel becomes one comprehensive special steel factory.  Although the epidemic isolates the people, however, it can’t isolate the service.

4140 steel provider OTAI shares the steel news with you.

Coronavirse as a “global pandemic”. The complexity and diversity of national governance and the region have brought many uncertainties to the epidemic prevention and control.  The global steel industry is facing a more complicated situation.

The hardest-hit areas of the epidemic contain 8 contries. They are China, Italy, South Korea, Spain, Germany, France, and the United States. Mainly look at the impact of the severely affected areas on the global steel industry.

The linkage between the steel industry and the economy can be considered from three aspects.

The first is relevance to the local economy. This can be simply observed by the ratio of apparent steel consumption to GDP. The larger the ratio value, the greater the proportion of industry in economic activities. the greater the impact of economic growth on steel. China and South Korea are significantly higher than the global level, and the local economy is strongly related to steel.

The second is the relevance to global trade, which can be observed by the scale of imports and exports. In 2018, the 8 countries’ contribution to the global steel trade was 70%, and the global trade of steel in 8 countries is intertwined. The outbreak of the epidemic will most likely harm the global steel trade.

The third is the relevance to indirect import and export products. Part of the steel is directly exported, and another part is through the import and export of finished products. such as steel products for mechanical and electrical, automotive, and home appliances. the impact of the epidemic on the steel industry in eight countries will have a significant impact on many industrial supply chains.

Generally speaking, the steel industry is very important in the global economy and supply chain system. The hardest-hit areas matter a lot, and the impact of the epidemic will have a profound impact!

Mr Jack Tan

Tel: 0086-769-23190193

Fax: 0086-769-88705839

Email: jack@otaisteel.com

4140 with thick of 45mm/41mm  is  super  suitable for the mask machine

With the outbreak of the pandemic around the world, we are immersed in a war without smoke, and we are all fighters, no one country is special. Many counties urgently need the mask, however, our  Otai company can provide 4140 with a thickness of 45mm/41mm, which is super suitable for the mask maschine.

OTAI Special Steel provides 4140 with thick of 45mm/41mm for FaceMask Machine. And we have more than 16 years provide special steel raw materials export experience to abroad .4140 is a chromium molybdenum alloy steel specification widely used in general purpose high tensile steel for components. Like axles, shafts, bolts, gears and other applications.

Similar to alloy grade AISI 4130 chrome moly alloy steel but with slightly higher carbon content. The higher carbon content of 4140 gives greater strength and heat treatment capabilities in comparison to AISI / ASTM 4130 alloy plates of steel. However, it does have inferior weldability characteristics.

properties of 4140 with thick of 45mm/41mm

AISI 4140  steel is chromium, molybdenum, manganese containing low alloy steel. It has high fatigue strength, abrasion and impact resistance, toughness, and torsional strength. The following datasheet gives an overview of AISI 4140 alloy steel.

4140 alloy steel material is a high-quality Quenched and Tempered Alloy Structural steel. It belongs to the high-quality medium carbon alloy steel, Oil Quenched & Tempered Hardness is 28-34 HRC.4140 Annealing delivery hardness less than 250HB.

Otai company is the biggest 42crmo4 stockist in the south of China. 4140 with a thickness of 45mm/41mm  is super suitable for the mask machine.we have storage in our factory. The storage is limited, please take your time to connect with me.

Mr Jack Tan

Tel: 0086-769-23190193

Fax: 0086-769-88705839

Email: jack@otaisteel.com

How to perform heat treatment on P20 steel?

If we know more about it ,we can take advantage of the p20 better. At the same time ,We can work efficiently.

heat treatment on P20 steel

The mass fraction of Mo in this steel reaches 0.46%, which can suppress the transformation of austenite to pearlite, improve the stability of austenite, and improve the hardenability and tempering resistance of steel. The simultaneous presence of Mo, Cr, and Mn can reduce or suppress the temper brittleness caused by other elements. If the mass fraction of Mo in the steel reaches 0.50%, the temper brittleness can be eliminated.

Mo has a solid solution strengthening effect on ferrite.and at the same time, it can improve the stability of carbides, improve the impact toughness and recrystallization temperature of the mold. that is, increase the creep resistance of ferrite at high temperature. It can effectively inhibit the cementite from growing up at 450 ~ 600 ℃ .It can promote the precipitation of dispersed special carbides, further strengthen the matrix, and enhance wear resistance.

what shall we pay attention to during heat treatment on p20 steel?

However, the high-temperature oxidation resistance of molybdenum (Mo) steel is poor. the protection of the die should be paid attention to during heat treatment. When Mo steel is heat-treated in a vacuum furnace, Mo will volatilize under a high vacuum. The vacuum should be adjusted in time. When the S element in the steel is high, low melting point eutectics of MoS and Fe will form, resulting in hot brittleness. Generally, Mo content When low, the impact is small.

This kind of steel is also called pre-hardened steel. that is, no heat treatment is performed after mechanical processing after quenching and tempering. The hardening and tempering temperature is 840 ~ 860 ° C, and the heat preservation coefficient is 30 ~ 45 s / mm. It should be preheated at 500 ~ 550 ° C to reduce thermal stress. The hardness after quenching the hot oil is 50 ~ 54HRC. 05 ~ 0.10μm. After tempering at 600 ℃ so that the hardness is controlled at about 30HRC for machining, the surface roughness after processing can reach Ra0. 05 ~ 0.10μm. The steel is added with S, Ca, B and other elements to become free-cutting steel. The hardness of heat treatment is controlled at 30 ~ 35HRC, which has good machinability and low surface roughness.

Mr Jack Tan

Tel: 0086-769-23190193

Fax: 0086-769-88705839

Email: jack@otaisteel.com

2311 & P20. Is a pre-hardened plastic mold steel that is widely used in the market,and the price is very low. They are like twins,because of the similar performance of 1.2311 and P20, and the chances of their occurrence are very high.

2311&P20 is a pre-hardened plastic mold steel that is widely used in the market

2311&P20 both price are not high. They are like twins,because of the similar performance of 1.2311 and P20, and the chances of their occurrence are very high. The application is very extensive. P20 mold steel is an American standard mold steel grade, which corresponds to the Chinese brand 3cr2Mo. In theory, P20 mold steel has a certain degree of wear resistance. After Q + T processing before delivery, the hardness is between 30-35HRC. Good processing performance, mold surface can be polished, mainly used for plastic molds that do not require high mold surface finish, long-term use, plastic mold life of about 100,000 times.

2311 is a German steel brand. It is a product based on 3Cr2Mo with fine-tuned alloy composition. It reduces the wear-resistant alloy-molybdenum content and increases the hardenable alloy composition-nickel content to increase Above 100mm, the uniformity of the surface hardness and core hardness of the 2311 mold steel. Its performance is similar to that of P20, and its application is also the same as P20. China ’s 2311 and P20 mold steels have achieved batch production, which minimizes the steelmaking cost of mold steels to meet the market’s low demand. Major steel mills have almost no longer produced P20 with 3Cr2Mo composition, and more than 90% of the mill have changed to 2311 mold steel with lower alloy content, which has been produced in batches. The original dimensions are 2.2-2.3 meters in width and 6 meters in length,or above. The price is getting close to the cost of carbon steel.

2311 & P20 advantages and disadvantages

The advantages of 2311 & P20 are that the output is very large and the price is very attractive. The disadvantage is that large-scale production of molds is easy to form segregation, resulting in uneven hardness, poor cutting performance, and hard drilling.

If you got a fake 1.2738, that’s because you got P20H actually.

Now some factories make the hardness of P20 higher ,it was named P20H. Some people pretend that P20H as 728H or OT718H,I know it will make some factories angry about this news，I just tell the truth. P20H is used for plastic molds, casing molds, Shell structural parts molds, large plastics for car seats, etc., some are also used for some precision plastic mold mold bases, cold die-cast mold bases, or mechanical parts that require wear resistance.

Ms Sharon Wan

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Email: Sharon@otaisteel.com

From the chemical composition and structural characteristics of H13 steel for aluminum extrusion.

H13 steel for aluminum extrusion of process control measures

From the chemical composition and structural characteristics of H13 steel for aluminum extrusion, it can be seen that the hot working process has a great impact on the structure and performance of H13 steel for aluminum extrusion molds. In order to prevent early failure of H13 steel molds, extend the service life and improve economic benefits, a scientific and reasonable Thermal processing technology.

1. Forging process

H13 steel for aluminum extrusion has high alloy element content, poor thermal conductivity, relatively low eutectic temperature, and is prone to cause overburning. For billets with a diameter larger than Ø70mm, it should be preheated in the range of 800 ～ 900 ℃, then heated at the initial forging temperature of 1065 ～ 1175 ℃. During the forging, the drawing and upsetting are performed multiple times. The total forging ratio is greater than 4.

2. Spheroidizing annealing process

The purpose of the spheroidizing annealing process is to homogenize the structure, reduce the hardness, improve the cutting performance, and prepare the structure for quenching and tempering. The spheroidizing annealing process is held at 845 ～ 900 ℃ (1h + 1min) / mm, and then furnace cooled to 720 ～ 740 ℃ isothermal (2h + 1min) / mm. Finally, the furnace is cooled to 500 ℃ and air-cooled. Granular pearlite, hardness is less than 229HBS. The spheroidization quality can be evaluated according to the first level diagram of GB / T1299-2000 standard.

3. Quenching and tempering process

The best heat treatment process of H13 steel for aluminum extrusion is oil-quenched or classified quenching after heating at 1020 ～ 1080 ℃, and then two tempering at 560 ～ 600 ℃. The microstructure is tempered tonite + tempered sorbite + residual carbide , Micro hardness is 48 ～ 52HRC. For molds (die-casting molds) that require high rigidity, the upper limit of the heating temperature can be used for quenching. For molds that require toughness (hot forging dies), the lower limit heating temperature can be used for quenching.

Ms Sharon Wan

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H13 steel mold should be fully preheated before work. When the preheating temperature is too high

H13 steel mold use and maintenance

Preheating of the H13 steel mold

HI3 steel has a high content of alloying elements and poor thermal conductivity, so the H13 steel mold should be fully preheated before work. When the preheating temperature is too high, the temperature of the mold is high during use, the strength is reduced, and plastic deformation is easy to occur, which causes the mold surface to collapse; when the preheating temperature is too low, the mold surface starts to use, the instantaneous surface temperature changes, thermal stress is large, and Initiation of cracks. After comprehensive consideration, the preheating temperature of the H13 steel mold is determined to be 250-300 ° C, which can reduce the temperature difference between the mold and the forging to avoid excessive thermal stress on the mold surface, and effectively reduce plastic deformation on the mold surface.

Cooling and lubrication of H13 steel mold

In order to reduce the heat load of the mold and avoid the mold temperature being too high, it is usually forced to cool during the intermittent work of the mold, which will cause the mold to periodically heat up, and the cooling effect will cause thermal fatigue cracks. Therefore, the mold should be slowly cooled after use, otherwise thermal stress will occur, which will cause the mold to crack and fail. H13 steel molds can be lubricated with water-based graphite with a graphite content of 12% to reduce the forming force and ensure the normal flow of metal in the cavity and the smooth release of the forgings. In addition, the graphite lubricant also has a cooling effect and can reduce H13 Working temperature of the steel mold.

Ms Sharon Wan

Mobile/WhatsApp: 0086-13580960968

Tel: 0086-769-23190193

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Email: Sharon@otaisteel.com

The manufacture of H13 hot work die steel molds has to go through a series of process links such as design

The manufacture of H13 hot work die steel molds has to go through a series of process links such as design, material selection, forging, annealing, machining and heat treatment. Improper process design or process operation in each process link will cause premature failure of the mold and reduce the service life of the mold. Hot work die steel often appears in the form of failure such as chipping, collapse, wear and cracking. The form, degree and location of failure of hot work die steel record the design, material selection, forging, annealing, machining and heat treatment to a series of process links. Important information.

Observe and analyze the macroscopic morphology, microstructure and failure form of the H13 hot work die steel mold at the failure location, and use theories and methods of metallography, material physics, and fracture mechanics to suggest the macromorphological features and materials at the H13 steel mold failure location The relationship between microstructure and failure form and mold design, material selection and processing technology, so as to propose scientific and reasonable process improvement measures.

(1) Analysis of chemical composition and metallurgical quality of raw materials

Improving the cleanliness of H13 hot work die steel, especially reducing the sulfur content is an effective measure to improve the life of H13 steel molds. The sulfur content of high-quality H13 steel is between 0.005 and 0.008%. H13 steel is a hypereutectoid steel with a relatively high alloy element content. Carbide segregation occurs during smelting and casting. The ingots form coarse carbide segregation zones after forging and rolling. Carbide segregation zone and casting residual dendrites, shrinkage, porosity and inclusion directly affect the microstructure and properties of H13 steel mold, which is one of the important reasons for the early failure of the mold. The analysis of the chemical composition and metallurgical quality of the raw materials can assess whether the raw materials are qualified, which can be used to guide the formulation of scientific and reasonable forging processes and heat treatment processes.

Test method

Sampling raw materials of H13 hot work die steel, analyzing its chemical composition, and assessing whether the chemical composition meets the requirements; cutting the sample from the center of the steel, grinding and polishing, etching with 4% nitric acid alcohol solution, inspecting it on an optical microscope Microstructure, grade of carbide segregation zone and inclusion grade according to relevant national technical standards.

(2) Analysis of mold microstructure

Microstructure analysis can determine whether there is carbide segregation zone in the mold failure location, large non-metallic inclusions, network carbides, eutectic carbides and tempered martensite; micro-area composition analysis can determine the chemical composition of the mold failure location Distribution characteristics; microhardness analysis can determine the mechanical properties of the mold failure location. Comprehensively analyze the microstructure, micro-hardness and micro-area composition at the failure location of the mold, reveal the macroscopic morphological features and the micro-mechanism of the failure form at the failure location of the mold, and correctly evaluate the current forging, spheroidizing annealing, quenching and tempering Technology, so as to propose scientific and reasonable process improvement measures.

Test method: Cut the sample from the failure position of the mold, grind and polish it, etch it with 4% nitric acid alcohol solution, inspect the microstructure on an optical microscope or scanning electron microscope, measure the hardness on a microhardness tester, Microdomain composition was determined on a spectrum analyzer.

Ms Sharon Wan

Mobile/WhatsApp: 0086-13580960968

Tel: 0086-769-23190193

Fax: 0086-769-88705839

Email: Sharon@otaisteel.com