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H13 application –chapter11

1. The lubrication and cooling of steel moldIn order for H13 steel  to decrease the heat load of mould, people always will make H13 steel cooling directly in the interval of work. However, this steel of H13  will cause a bad impact on the mold. It should be cool slowly to avoid thermal stress and cracking during the process of H13 . Need to use the graphitic lubricant to make sure the H13 steel die work in the right way. Its power of  H13 radiating is great. That will decrease the temperature of H13 mold at the time of work.

How to fix it for H13 steel mould ?

• Analysis of chemical composition and quality of material

Raise the purity of H13 steel. Decrease the content of sulfur which is the most efficient way to increase the working life of H13 steel mold. The sulfur content is at the range of 0.005-0.008% of high-quality H13 steel.

According to the analysis of chemical composition and quality of material can get the result of if it is eligibility. That will help us to make the right decision on the technology of heat treatment and forging for H13 mould steel . Test Method: Sampled the H13 steel stuff to analyze its chemical composition and if it complies to the requirements. And take the sample at the steel center. Then grinding, polishing, etching with 4% nitric acid alcohol solution, examining the microstructure on an optical microscope, and assessing the grade of carbide segregation and the grade of inclusion according to relevant national technical standards.

• The way of technology control for H13 steel

1. Forging Technology The ingot that diameter bigger than 70mm must preheat at the temperature range of 800-900℃. Then, it is heated at an initial forging temperature of 1065 to 1175 ° C. And the total forging ratio must bigger than 4.
2. Spheroidizing Annealing It can make the strength get lower and improve the cutting machining properties. Do a good start for quenching and tempering. The spheroidizing annealing process is maintained at 845℃ to 900℃(1 h +1 min)/mm. And then cooled to 720℃ ~ 740℃ isothermal (2h + 1 min)/mm at the furnace. Cooling to 500 ° C at the furnace, and finally out of the furnace to air-cooled.
3. Quenching and Tempering Technology There is the best way of H13 steel heat treatment technology. After heating at 1020°C~1080°C, then oil hardening or martempering. Tempered twice at 560-600 °C. The microstructure is tempered toughness + tempered sorbite + residual carbide, and the microhardness is 48-52HRC.

The manufacture of H13 steel die must do a good job at design, the material chosen, forging, annealing, heat treatment and etc to make sure the quality at a high level. Every step is important and has a big influence on the mold product.

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H13 steel manufacturing technique-Forging Technology;Cutting;Grinding;electric spark;Heat treatment technology

H13 steel manufacturing technique effect the used of  steel

Today,I collated some data from the internet,about the which processing will effect the used of steel.

(1) Forging process

H13 steel contains a lot of alloying elements, has a large resistance to deformation during forging, and has poor thermal conductivity of the material. The eutectic temperature is low, and it will overheat if you pay little attention. Therefore, when heating, it should be preheated in the range of 800 ～ 900 ℃, and then heated to the starting forging temperature of 1065 ～ 1175 ℃. In order to crush large non-metallic inclusions, eliminate carbide segregation, refine carbides, and even structure, repeat upsetting and upsetting during forging, and the total forging ratio is greater than 4. During the cooling process after forging, there is a tendency that quench cracks occur, and lateral cracks are liable to occur in the core. Therefore, H13 steel should be slowly cooled after forging.

(2) Cutting

The surface roughness of the cutting process has a great impact on the thermal fatigue performance of the mold. The mold cavity surface should have a low surface roughness without leaving knife marks, scratches and burrs. These defects cause stress concentration and induce thermal fatigue crack initiation. Therefore, during the processing of the mold, the corner radius of the complex part must be prevented from leaving knife marks, and the burrs on the edges of the holes, grooves and roots must be polished away.

(3) Grinding

During the grinding process, local frictional heat easily causes defects such as burns and cracks, and generates residual tensile stress on the grinding surface, which leads to premature failure of the mold. Burning caused by grinding heat can temper the surface of the H13 mold until tempered martensite is formed. The brittle untempered martensite layer will greatly reduce the thermal fatigue performance of the mold. If the grinding surface is locally heated above 800 ° C and the cooling is insufficient, the surface material will be re-austenitized and quenched into martensite, so the surface layer of the mold will generate high structural stress, and the grinding process The extremely rapid temperature rise of the middle mold surface will cause thermal stress, and the superposition of tissue stress and thermal stress will easily cause grinding cracks in the mold.

Next Chapter,I shall organize the rest,the other H13 steel manufacturing process.

Ms Sharon Wan

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Tel: 0086-769-23190193

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H13 (4Cr5MoSiV1) is a hot-working die steel widely used in the world. It has high thermal strength and hardness

H13 (4Cr5MoSiV1) is a hot-working die steel widely used in the world.

It seems I had wrote much about H13 die steel but my friends told me that  it’s ramdon data,they want a complete data,so I serch alot,and organized it.

It has high thermal strength and hardness, high wear resistance and toughness, and good thermal fatigue resistance. Hot extrusion dies and die casting dies for aluminum, copper and their alloys. Hot work die steel is subject to large impact loads, strong friction, thermal stress caused by severe cold and heat cycles, and high temperature oxidation, and often failure modes such as chipping, collapse, wear, and cracking.

AISI H13 Chemical composition

Its chemical composition characteristics:

① Medium carbon, with a mass fraction of 0.32 to 0.45%, to ensure high hardness, high toughness and high thermal fatigue resistance.

② Add more elements Cr, Mn, Si to improve hardenability. Mn can change the nature and shape of the oxides formed during solidification of the steel, avoid sulfur forming low melting point FeS on the grain boundaries, and exist as a certain plastic MnS, thereby eliminating the harmful effects of sulfur and improving the heat of H13 die steel Workability; Cr and Si can improve tempering stability.

③ Add elements Mo and V that cause secondary hardening. Mo and V can also prevent the second type of tempering brittleness and improve the tempering stability.

The failure problem of H13 steel mold is a very complicated technical problem, which can be analyzed from four aspects: material, design, manufacturing and use.

Chemical composition and metallurgical quality

H13 die steel is a type of hypereutectoid alloy steel. There are many defects in the structure such as non-metallic inclusions, carbide segregation, center porosity and white spots, which greatly reduce the strength, toughness and thermal fatigue resistance of mold steel. H13 steel is generally divided into ordinary H13 steel and high-quality H13 die steel according to quality. Due to the use of more advanced production technology, high-quality H13 steel has pure steel, uniform structure, slight segregation, and higher toughness and thermal fatigue properties. Ordinary H13 steel must be changed to forge to crush large non-metallic inclusions, eliminate carbide segregation, refine carbides, and homogenize the structure.

Mould Design

When designing the mold, the external dimensions of the module should be determined according to the material and geometric dimensions of the formed part to ensure the strength of the mold. In addition, excessively small fillet radii, wide and thin wall sections with wide and thin wall sections, and improper positions of holes and grooves can easily cause excessive stress concentration and initiation of cracks during mold heat treatment and use. Therefore, avoid sharp corners as much as possible in the design of the mold, and the holes and slots should be arranged reasonably.

Ms Sharon Wan

Mobile/WhatsApp: 0086-13580960968

Tel: 0086-769-23190193

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Email: Sharon@otaisteel.com

What’s the difference between sup6 and sup9?

Today, I receive an email from a client about sup6 steel. What’s the sup6 steel, what’s the difference between sup6 and sup9?

Although 4140 is the main product of the otai company, however, the sup9 is available if you need it. I will tell you the details about it.

Sup6 and sup9 both belong to the spring steel, spring steel is widely used in our daily life. even ballpoint pens we use are equipped with springs. It is also used in much mechanical equipment.

Features and Scope of sup6

sup6 Is widely used silicon manganese spring steel, strength, flexibility, and hardenability than 55Si2Mn. Suitable for railway vehicles, bear a greater load on the automobile and tractor industries flat spring or coil spring 30mm or less in diameter, and is also suitable for the production of working temperature below 250 ℃ non-corrosive medium heat and withstand alternating load spring and under high stress the important work of the large spring roll. High silicon content (Wsi) (up to 2.00%). High strength and good elasticity. Good resistance to tempering. Easy to decarburize and graphitize. Hardenability is not high. Manufacture of various springs, such as leaf springs, coil springs for automobiles, locomotives, tractors, cylinder safety valve springs.

Chemical Composition:

Carbon C: 0.56 ~ 0.64

Si Si: 1.50 ~ 2.00

Mn Mn: 0.60 ~ 0.90

Sulfur S: ≤0.035

Phosphorus P: ≤0.035

Chromium Cr: ≤0.35

Ni Ni: ≤0.35

Copper Cu: ≤0.25

SUP9-Characteristics

Sup9 Steel is a high-quality cold work spring steel. It belongs to high carbon alloy spring steel. Oil quenched and tempered hardness is 28-34 HRC. Sup9 annealing delivery hardness less than 250HB.

The outstanding advantage is that it has good hardenability, and also has good hot workability, comprehensive mechanical properties, and decarburization resistance. Various important springs with large cross-sections, such as large leaf springs and coil springs for automobiles and locomotives.

Chemical Composition:

Carbon C: 0.52 ~ 0.6

Si Si: 0.15~ 0.35

Mn Mn: 0.65~ 0.95

Sulfur S: ≤0.035

Phosphorus P: ≤0.030

Chromium Cr: 0.65~ 0.95

Mr Jack Tan

Tel: 0086-769-23190193

Fax: 0086-769-88705839

Email: jack@otaisteel.com

H13 steel is a C-Cr-Mo-Si-V steel, and its application in the world is extremely common.

H13 steel is a C-Cr-Mo-Si-V steel

H13 steel application in the world is extremely common. At the same time, many scholars in various countries have conducted extensive research on it and are exploring the improvement of chemical composition. Steel is widely used and has excellent characteristics, which are mainly determined by the chemical composition of steel. Of course, the impurity elements in steel must be reduced. Some data show that when Rm is 1550MPa, the sulfur content of the material is reduced from 0.005% to 0.003%, which will increase the impact toughness by about 13J. Obviously, the NADCA 207-2003 standard stipulates that the sulfur content of the premium H13 steel is less than 0.005%, while the superior should be less than 0.003% S and 0.015% P. The composition of H13 steel is analyzed below.

Carbon: American AISI H13

UNS T20813, ASTM (latest version)H13 steel and FED QQ-T-570 H13 steel have carbon content of (0.32 ~ 0.45)%, which is the most carbon content range of all H13 steels Wide. The carbon content of German X40CrMoV5-1 and 1.2344 is (0.37 ~ 0.43)%, and the carbon content range is narrow. German DIN17350 also has the carbon content of X38CrMoV5-1 (0.36 ~ 0.42)%. The carbon content of Japan SKD 61 is (0.32 ~ 0.42)%. The carbon contents of 4Cr5MoSiV1 and SM 4Cr5MoSiV1 in GB / T 1299 and YB / T 094 in China are (0.32 ~ 0.42)% and (0.32 ~ 0.45)%, which are the same as SKD61 and AISH13, respectively. In particular, the North American Die Casting Association NADCA 207-90, 207-97, and 207-2003 standards specify the carbon content of H13 steel as (0.37 ~ 0.42)%.

If  you need more information of H13,please do not hesitate to contact us.

Ms Sharon Wan

Mobile/WhatsApp: 0086-13580960968

Tel: 0086-769-23190193

Fax: 0086-769-88705839

Email: Sharon@otaisteel.com

2738 mold steel is a German DIN standard steel grade. It has good mechanical properties and good process ability

2738 mold steel is a German DIN standard steel grade.

It has good mechanical properties and good process ability, so it is widely used in the mold industry. Among them, it is mainly used for the production of plastic molds.

Since the 2738 mold steel has been pre-hardened,when it leaves the factory, it can be directly used for processing, thereby reducing the heat treatment,link in the normal mold production,it processing and improving economic benefits.It’s pre-hardened plastic mold steel,executes standard 29-33HRC.

2738 with about 1% nickel content, good pre-hardness. Due to the addition of the nickel element, its harden ability is improved, and the hardness distribution of large sections,and thick plates is uniform. It is mainly used in large plastic molds and mold bases, such as automobile bumpers and TV shell molds. Suitable for molds requiring high lightness, such as the production of hard rubber (PS),and ultra-hardened rubber (ABS), etc., its characteristics are: excellent processing performance, easy cutting and polishing and electrical corrosion performance.

Nickel is added to 2738 steel to achieve uniform hardness,with superior processing,and polishing properties. Mainly used in high-demand plastic molds, suitable for plastic molds such as televisions, fax machines, plastic parts for home appliances, and automotive parts that require a certain degree of polishing.

German plastic mold steel 2738H is hardened

The nickel component is added to the steel, the hardness is uniform, and it has superior process ability,and polishing performance.China’s GB standard grade 3Cr2NiMo, American AISI standard grade P20 MODIFIED, American AISI standard grade P20 + Ni, German DIN standard grade 1.2738.

Carburizing treatment:F

Carburizing treatment temperature is 850-940 ℃, and the time is determined by the depth of product demand. If the carburizing temperature exceeds 880 ° C ,and the time exceeds 2 hours, normalization treatment must be performed,to keep the structure grains fine. After carburizing, it is cooled to 830 ° C in a furnace, soaked in oil after soaking, and then tempered to increase surface hardness and increase wear resistance. If only hardness is required without fine grains, it can be quenched at a carburizing temperature above 880 ℃

Ms Sharon Wan

Mobile/WhatsApp: 0086-13580960968

Tel: 0086-769-23190193

Fax: 0086-769-88705839

Email: Sharon@otaisteel.com

A friend told me recently that it seems I did not write about plastic mold steel for a long time.

A friend told me recently that it seems I did not write about plastic mold steel for a long time.OK, Let’s talk about plastic mold steel. Plastic mold steel is mainly divided into 3 types, pre-hardened plastic mold steel, and the second type has anti-corrosion and rust prevention functions. The third is wear-resistant one, of which the pre-hardened one, ordinary plastic mold steel, and the second is a corrosion-resistant mold steel, a pre-hardened plastic mold with anti-rust function. Steel, pre-hardened plastic mold steel with certain wear resistance.

Pre-hardened plastic mold steel

It means that it has been quenched and tempered by factory directly. The mold steel is supplied in a state of hardness. The common hardness is generally between 28-44HRC. The ordinary pre-hardened mold steel is 1.2311, P20. , 738H, 738,OT718,OT718H, NAK80,2316H. 2083H, S136H, etc., this kind of mold steel with hardness, please refer to the following information.

Applications of 1.2311 steel

1.2311 Tool steel 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.

Supply form of 1.2311 steel

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.

Ms Sharon Wan

Mobile/WhatsApp: 0086-13580960968

Tel: 0086-769-23190193

Fax: 0086-769-88705839

Email: Sharon@otaisteel.com

P20 Steel Plate Mold Steel Sales Promotion after Coronavirus in March from China OTAI Special Steel . We have many stock to provide . Please pay attention to that there is no influence for Chinese Steel market price and reserve . Becasue the situation have caused in Chinese Spring Festival holiday . And after it happened , the government have strictly controlled on this . And all people here was fine and The mill was restored to full working order . Any new inquiry , please working as before .

P20 Steel Plate Mold Steel Sales Promotion after Coronavirus in March from China OTAI Special Steel . We have many stock to provide AISI P20 Steel Plate Material is a versatile . Low-alloy tool steel that is characterized by good toughness at moderate strength levels .

The special purpose mold steel P20 steel plate is commonly used for plastic injection mold cavities and tooling and for die casting dies for zinc . P20 mold steel plate material is typically sold in the pre-hardened condition at a hardness of approximately 300 HBW.

P20 Steel Plate Mold Steel  differs from area to area in the different countries.Europeans generally use the DIN spec-DIN EN ISO 4957 standard materials (1.2311 and 1.2312), while in Japan steel industry standard, PX5 is the new standard P20. And the Americas Countries, Grade steel P20 is the most and wide used steel grade material. In China, 3CrM2Mo is the P20 steel grade equivalent, which is in the standard GB/T 1299 tool steel specification.

P20 Steel Plate Mold Steel  are nitrided or carburized. These P20 mold steel materials steels are capable of being machined into complex and large dies and molds. Material P20 steel plate and round bars are mostly used in the carburized condition. The presence of chromium and nickel enhances the toughness and hardness of mold steel P20 grade material.

Tel: 0086-769-23190193

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SCM439,otai have more than 16 years of experience in it.

Recently, some clients send me the mail about the SCM439.what’s this kind of steel it is? Its other commonly used name is 4340, it is one of our main products. We received the repeat order every month, just like 4140. our otai company leaves a good impression on our customers. I hope you will have a try.

The women’s day is around the corner, to celebrate the festival, our company send every member a branch of flower, it is special. otai company not only cares about the client but also the employees.I am honor to be a member of our company. I think the development of a company is based on the unity of every member of the company. I think the future of otai company will be better and better.

Today, let’s talk about the SCM439 with you. AISI /SAE 4340 Steel is an Alloy Structural Steel belong to ASTM A29/A29M Steel Grade standard. AISI 4340 used in Oil and Gas industry and Large Machinery Structural. 4340 Steel China Supplier and factory Otai Special Steel Supply 4340 steel in Round bar, Plate, Flat bar, Square, Forging Ring, and others any shape. And provide cutting, sawing, milled, machining processing.

Supply Range of AISI 4340 Alloy Steel

AISI 4340 Steel Round Bar: diameter 5mm – 400mm

SAE 4340 Steel Plate: thickness 5 –500mm x width 200– 2300mm

ASTM 4340 Steel Block: 210mm x 500-810mm

ASTM 4340 steel is an alloy structural steel, 4340 is used for engineering structural, Used as require good toughness, high strength, as well as the important conditioning of large size, heavy machinery such as high load of axial, turbine shaft, larger than 250 mm in diameter of helicopter rotor shaft, turbojet engine turbine shaft, blade, high load of transmission parts, fasteners of the crankshaft. Gear, etc.

Mr Jack Tan

Tel: 0086-769-23190193

Fax: 0086-769-88705839

Email: jack@otaisteel.com

42CrMo4 Steel Pipe Stocklist For Sales Promotion from China after coronavirus . In March , we have received many demands for 42CrMo4 Steel Pipe . Luckly we have many stocklist for this production . And all the measure are according to Chinese regular production size . One out diameter have many different wall thickness to choose .

42CrMo4 Steel Pipe Stocklist For Sales Promotion from China after coronavirus  from OTAI Special Steel . In March , We have received new inquiry from Turkey , Argentina …… for 42CrMo4 Steel Pipe .  And recently we have planned to provide sales promotion for this materials . Because for we have many stock in various out diameter and wall thickness to meeting all your request . Please contact with us urgently . The Inventory is reduced daily . The stock may sold out for some special size .

42CrMo4 Steel Pipe Stocklist Mechanical Tubing are medium carbon alloy grades . Which are widely used for many general-purpose applications that require high tensile strength and toughness . Alloy tubing is an excellent candidate for most processing techniques . Where strength is required and allows for many options due to its available sizes produced .

42CrMo4 Steel Pipe Stocklist alloy tubing is easiest of the common alloy grades to be machined . With a minimal stock allowance for clean-up . It has excellent machining characteristics and is a medium carbon alloy.

42CrMo4 Steel Pipe Stocklist is usually supplied ready heat treated to hardness in 18-22 HRC .  If further heat treatment is required, then heat to 840 oC – 875 oC, hold until temperature is uniform throughout the section . Soak for 10 – 15 minutes per 25 mm section, and quench in oil, water, or polymer as required .

Welcome to inquiry with us 42CrMo4 steel pipe , and we also have other steel pipe AISI 1020 and 1045 . Some less quantities with 4130 tubes , please send request for get the quotation .

jack@otaisteel.com

Tel: 0086-769-23190193

Fax: 0086-769-88705839

Email: jack@otaisteel.com