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The material of 42CrMo4 for gear forgings must first meet the requirements of working conditions.

DIN 42CrMo4 for gear equivalent material

♦JAPAN♦ : JIS SCM440 alloy steel

♦American♦ : AISI/ASTM 4140 steel alloy

♦CHINA♦ :  GB 42CrMo steel

♦BRITISH♦ : BS 708M40

The material of 42CrMo4 for gear forgings must first meet the requirements of working conditions.

The requirements of working conditions are the factors that should be considered first when selecting gear forging materials. Alloy steel is often used to make gear forgings with high speed, heavy load and working under impact loads, such as gears used in aircraft. High reliability is required, so alloy steel with high mechanical properties must be selected. If the gear size is required to be as small as possible, surface-hardened high-strength alloy steel should be used. The gear transmission in mining machinery generally has large power, low working speed, and extremely high dust content in the surrounding environment. Therefore, cast steel or cast iron are often selected. The power of household and office machinery is very small, but it requires stable transmission, low noise or no noise, and can work normally with little or no lubrication. Therefore, engineering plastics are often used as gear materials.

The choice of 42CrMo4 for gear forging materials should consider the gear size

Blank forming method and heat treatment process. Large-sized gears generally use cast blanks, and cast steel or cast iron can be used as gear materials. Gears with high requirements for medium or below medium size often use forged blanks, and can be made of forged steel. When the size is small and the requirements are not high, round steel can be used as the blank.

Function of 42CrMo4 for gear

42CrMo for gear steel is a high quality Quenched and Tempered Alloy Structural steel . It belong to the high quality medium carbon alloy steel, Oil Quenched & Tempered Hardenss is 28-34 HRC . 42CrMo Annealing delivery hardenss less than 250HB . This materials was the best choose for produce bolt and screw .

Ms Sharon Wan

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42CrMo4 steel gear forgings have higher fatigue strength limit and resistance to multiple impacts.

42CrMo4 steel gear compared with 40Cr forged gears

Compared with 40Cr forged gears, 42CrMo4 forged gears are better than the former, especially the hardenability is higher than 40Cr steel gears. After quenching and tempering, 42CrMo4 steel gear forgings have higher fatigue strength limit and resistance to multiple impacts, and the low temperature impact toughness is good.

Chemical composition

The main chemical composition (mass fraction) of forged gear 42CrMo4 steel is: 0.38% ~ 0.45% c, 0.17% ~ 0.37% Si, 0.50% ~ 0.80% Mn, 0.90% ~ 1.20j% Cr, 0.15% ~ 0.25% Mo, ≤ 0.30% Ni, ≤0.030% P, ≤0.030% S.

The phase transition points are: Ac1730 ℃, Ac3800 ℃, Ms310 ℃.

Forging 42CrMo4 steel gears, the initial forging temperature is 1130 ~ 1180 ℃, and the final forging temperature is 850 ℃. After forging, the diameter size is more than 50mm and it needs to be cooled slowly.

The carbon content of 42CrMo4 steel gear is kept at about 0.42%, which ensures that the steel has a good combination of strength and toughness. The addition of Cr and Mo elements is mainly to improve the hardenability of steel. When quenching and heating, Cr and Mo elements are completely dissolved in austenite to improve the hardenability of steel. After quenching, Cr and Mo elements solid solution strengthen the matrix structure and improve the tempering stability of the matrix structure. During high temperature tempering, some Cr and Mo elements diffuse from the matrix structure to the precipitated cementite Fe3C to form alloy cementite (Cr, Mo, Fe) 3C. In addition, the addition of Mo element can eliminate the temper brittleness. Adding a small amount of Ni element can improve the toughness of steel.

There are many factors to consider when choosing. In general, the working conditions of gear forgings are different, and the damage form of gear teeth is different. It is the basis for determining the calculation criterion of gear strength, selecting materials and heat treatment.

–                                                                                                 -To be continued

Ms Sharon Wan

Mobile/WhatsApp: 0086-13580960968

Tel: 0086-769-23190193

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There are many types of materials for gear forgings. The commonly used materials for gear forgings are: 40Cr, 42CrMo4, 20CrMnMo, 20CrMnTi, etc.

42CrMo4 forged and 40Cr forged gears are mostly the most large-scale gear forgings in the lifting industry.

The small piece has no owner (reference). Most gears require gears to improve quality. The heat treatment hardness of the gears can reach the best performance at 38-42HRC. The toughness of 42CrMo4 is much better than 40Cr, because the former has better heat treatment hardenability, which is closely related to its material. Also, the strength at the same hardness is very close. In the best performance, the tensile strength of 40Cr is 60 ~ 75 kg / mm ;the yield strength is 35 ~ 55 kg / mm; the tensile strength of 42CrMo4 forged is 110 kg / mm;the yield strength is 95 kg / mm, obviously 42CrMo4 performance is much better than 40Cr performance.

Hardness

40Cr material has good hardenability, it can be hardened to 28 ~ 60mm in diameter when water quenching, and 15 ~ 40mm in diameter when oil quenching. After tempering, the material has good comprehensive mechanical properties, and has good low notch sensitivity and low temperature impact toughness. After 40Cr gear forgings are quenched and tempered, they are often subjected to surface induction hardening or nitriding. When the hardness is 174 ~ 229HBS, the cutting performance is better, the relative cutting workability is 60%, the carbon content of 40Cr forgings is maintained at about 0.40%, to ensure that the steel has a good combination of strength and toughness. The addition of Cr element is mainly to improve the hardenability of steel. When quenching and heating, Cr element is completely dissolved in austenite, which improves the hardenability of steel. After quenching, Cr element solid solution strengthens the matrix structure and improves the tempering stability of the matrix structure. During high temperature tempering, some Cr elements diffuse from the matrix structure to the precipitated cementite Fe3C to form alloy cementite (Cr, Fe) 3C.

Chemical components

The main chemical components of 40Cr steel for gear forgings are: 0.37% ~ 0.44% C, 0.17% ~ 0.37% Si, 0.50% ~ 0.80% Mn, 0.80% ~ 1.10% cr, ≤0.035% P, ≤0.035% S

The phase transition points are: Ac1770 ℃, Ac3805 ℃, Ms328 ℃.

The initial forging temperature of 40Cr gear forgings is 1100 ~ 1150 ℃, and the final forging temperature is 800 ℃. After forging, the size needs to be cooled slowly when the size is more than 60mm.

-To be continued

Ms Sharon Wan

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Tel: 0086-769-23190193

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What is the role of cr (chromium) in 42CrMo4 seamless steel pipe? Use chromium, the chemical symbol Cr, and the element is steel gray metal.

What is the role of cr (chromium) in 42CrMo4 seamless steel pipe?

The element name comes from the Greek, which originally meant “color” because chromium compounds all have color. Obtained with carbon reduction. The content of chromium in the crust is 0.01%, ranking 17th. There is no free chromium in nature, mainly in chromite. In the periodic table, it belongs to group ⅥB. The atomic number of chromium is 24, the atomic weight is 51.9961, and body-centered cubic crystals. The oxidation number is 6, 5, 4, 3, 2, 1, −1, −2, −4 and it is the hardest metal.

The decisive role of chromium in stainless steel gold

42CrMo4 seamless steel pipe is only one element that determines the nature of stainless steel. This is chromium. Each stainless steel contains a certain amount of chromium. To date, there is no chromium-free stainless steel. The fundamental reason why chromium becomes the main element that determines the performance of stainless steel,it’s the addition of chromium to steel, as an alloy element promotes the development,the internal contradictory movement in favor of resisting corrosion damage. This change can be explained from the following aspects: ① Chromium increases,the electrode potential of the iron-based solid solution ② Chromium absorbs iron electrons to passivate the iron, the passivation is due to the anode reaction is prevented,and the corrosion resistance of the metal and alloy is improved phenomenon. There are many theories that constitute the passivation of metals and alloys, mainly including thin film theory, adsorption theory and electron arrangement theory.

Chromium is used to make stainless steel, auto parts, tools, tapes and video tapes. Chrome plated on the metal can prevent rust, also known as dormitory, strong and beautiful.

Chromium can be used to make stainless steel. The color of red and emerald also comes from chromium. As the most important metal in modern technology, chromium-nickel steel fused in different percentages is ever-changing, and there are many kinds of incredible. The toxicity of chromium is related to its existing valence state. Hexavalent chromium is 100 times more toxic than trivalent chromium ,and it can be easily absorbed by the body and accumulated in the body. Trivalent chromium and hexavalent chromium can be converted into each other. Natural water does not contain chromium; the average concentration of chromium in seawater is 0.05ug / l; lower in drinking water. The sources of chromium pollution include sewage discharged from the processing of chromium-bearing ores, metal surface treatment, leather tanning, printing and dyeing, etc.

Ms Sharon Wan

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Acero M2

El acero para herramientas M2 es acero de alta velocidad de tungsteno-molibdeno con una composición de carbono bien equilibrada y alta tenacidad.

¿Qué es el Acero M2?

El acero para herramientas M2 es acero de alta velocidad de tungsteno-molibdeno con una composición de carbono bien equilibrada y alta tenacidad. También se llama acero JIS SKH51 y DIN 1.3343. Es fácil sobrecalentar, controlar la temperatura de calentamiento de enfriamiento es necesario y los requisitos de protección del tratamiento térmico son estrictos. Se usa ampliamente para hacer herramientas de corte debido a su gran dureza y resistencia al desgaste. Ha reemplazado el acero de alta velocidad T1 en la mayoría de las aplicaciones, se ha convertido en la primera opción del cliente debido a su gran rendimiento y relación de precio de rendimiento extremadamente alto. Las propiedades del acero y el tratamiento térmico son las siguientes.

1.3343 Características del acero

1. Dureza (estado original de fábrica): ≤255HB
2. Temperatura de endurecimiento: 1220 ℃ -1240 ℃
3. Dureza (después del tratamiento térmico): ≤63HRC
4. Es una gran opción en aplicaciones de corte debido a su gran resistencia al desgaste y tenacidad.
5. Carburo distribuido uniformemente y alta tenacidad.
6. Se puede utilizar para hacer fresas, escariadores, brochas, cortadoras de engranajes y otras herramientas de la industria.

Tratamiento térmico de acero M2 y producido

Maquinabilidad

La conformación de aceros para herramientas M2 puede ejecutarse utilizando estrategias de rectificado. Pero, que tiene mala capacidad de molienda. Por eso se les llama acero para herramientas de maquinabilidad «mediana» en condiciones de recocido. La maquinabilidad de estos aceros es solo el 50% de la de los aceros para herramientas de endurecimiento por agua o grupo W fácilmente mecanizables.

Recocido

Calentar a 1600 ° F, remojar completamente al calor. El horno se enfría 25 ° F por hora a 900 ° F, el aire se enfría a temperatura ambiente. Dureza recocida aproximada 241 Brinell máximo.

Alivio de la tensión del material sin endurecer: Caliéntelo lentamente de 1200 a 1250 ° F. Remoje durante dos horas por pulgada de espesor al calor. Enfriamiento lento (horno frío si es posible) a temperatura ambiente.

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OT718  mold steel

After forging and rolling, the structure is dense, 100% ultrasonic inspection, no pores, pinhole defects.

1. a) The template of the large mold, the high surface requires household appliances.
2. b) Suitable for large mirror plastic molds, such as automobiles, home appliances, audio and video products, etc.
3. c) Can be used for plastic molds with mirror polishing requirements, suitable for injection molds, blow molds for PA, POM, PS, PE, PP, ABS plastics.
4. d) High polishing and demanding mold cavity.                                                                                                                                Hardened

In order to improve the service life of the mold to more than 800,000 mold times, the pre-hardened steel can be implemented by hardening and low-temperature tempering. When quenching, first preheat at 500-600 ℃ for 2-4 hours, and then keep it at 850-880 ℃ for a certain period of time (at least 2 hours), put it in oil and cool it to 50-100 ℃, and leave it to air-cool. -52HRC, in order to prevent cracking, a low temperature tempering treatment at 200 ° C should be performed immediately. After tempering, the hardness can be maintained above 48HRC.

Collapse this section nitriding

Nitriding treatment can obtain high hardness surface layer structure, the hardness of the surface layer after nitriding reaches 650-700HV

(57-60HRC) The life of the mold can reach more than 1 million times. The nitrided layer has the characteristics of dense organization and smoothness. The mold release property and the resistance to humidity and alkali corrosion are improved.

Quenching and tempering

Quenching temperature 840 ~ 870 ° C, tempering temperature 200 ~ 500 ° C, hardness 50 ~ 55HRC

Edit the material properties of this paragraph

Folding physical properties

(Sample hardness 340HBW, at room temperature and high temperature)

1) Temperature 20 ° C / 200 ° C / 400 ° C, density 7.8g / cm / 7.75g / cm / 7. 7g / cm.

2) Temperature 20 ~ 200 ° C / 20 ~ 400 ° C, coefficient of linear expansion: 12.6 × 10K / 13.5 × 10K.

3) Temperature 20 ° C / 200 ° C / 400 ° C, thermal conductivity 29.0W · (m · K) /29.5W· (m · K) /31.0W· (m · K)

4) Temperature 20 ° C / 200 ° C / 400 ° C, elastic modulus: 205000MPa / 200000MPa / 185000MPa

Folding mechanical properties

(Sample hardness 340HBW)

1) Temperature 20 ° C / 200 ° C / 400 ° C, tensile strength 1100MPa / 1050MP8 / 850MPa.

2) Temperature 20 ° C / 200 ° C / 400 ° C, conditional yield strength 980MPa / 925MPa / 770MPa.

3) Temperature 20 ° C / 200 ° C / 400 ° C, reduction in area of ​​49% / 51% / 52%

4) Temperature 20 ° C / 200 ° C / 400 ° C, elongation 13% / 14% / 16%

5) Temperature 20 ° C / 200 ° C / 400 ° C, impact toughness (≥) 20J / cm / 32J / cm / 42J / cm

Critical temperature

critical point

Temperature (approximate) / ℃

Expand the expansion coefficient of this paragraph

Temperature / ℃

Linear (expansion) expansion coefficient / C

Edit the thermal conductivity of this paragraph

Temperature / ℃

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1.2738 mold steel

1.2738 is a very common German standard plastic mold steel, usually referred to as 738 for short.

Performance characteristics

① Excellent polishing and photoetching performance;

②Good machining performance;

③ High purity and uniformity;

④ Uniform hardness;

⑤ Follow-up nitriding treatment or local flame quenching can be used to improve surface strength and surface wear resistance and reduce surface failure.

Compared with the traditional plastic mold steel P20, 1% nickel is added to OT718, which has better toughness and hardenability, and performs better in molds with large cross-section sizes. This type of steel is suitable for large-scale, especially thicker than 400mm, plastic molds that require uniform hardness, high toughness, and good surface polishing performance, such as TV frames and back shells, copier cases, bumpers, shock absorbers, instrument panels, etc. Large molds, as well as trash can molds, die-casting mold holders, etc.

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34CrNiMo6 round steel, does this kind of steel suitable for your company? It is the hot sales of the Otai company. Last year, we sold a lot of steel abroad .why clients repeat the order from our company? I want to share some information about the 34CrNiMo6 with you.

34CrNiMo6 round steel, does this kind of steel suitable for your company? It is the hot sales of the Otai company. Last year, we sold a lot of steel abroad .why clients repeat the order from our company? I want to share some information about the 34CrNiMo6 with you.

One of our clients from Singapore bought the 34CrNiMo6 round steel from our company .this is a company served the marine and offshore industry .specialising in marine pipes and fittings and engineering services. 34CrNiMo6 steel is the perfect material applies to the requirement of their company. Our customer is satisfied with our product.

34CrNiMo6 Alloy Steel is a quenching and tempering steel with high strength, high toughness, and good hardenability. A heat treatable, low alloy steel containing nickel, chromium, and molybdenum as per DIN Germany standard.

34CrNimo6 steel has high strength, high toughness, and good hardenability. EN / DIN 34CrNiMo6 alloy steel has the stability of resistance to overheating, but the white sensitivity of 34CrNiM06 is high. It also has the temper brittleness, so the weldability of 34CrNiMo6 material is poor. The steel 34CrNiMo6 needs high temperature preheating before welding to eliminate the stress after welding processing.

Application of 34CrNiMo6 round steel

34CrNiMo6 alloy structural steel is used in ships, vehicles, aircraft, missiles, weapons, railways, bridges, pressure vessels, machine tools, etc. 34CrNiMo6 European standard alloy structural steel grade, corresponding to China’s grade 34Cr2Ni2Mo, is a typical difficult-to-machine material, widely used in the manufacture of engine camshafts and connecting rods and other important parts.

Mr Jack Tan

Tel: 0086-769-23190193

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1.2312 Sheet plate suitable for make plastic mould , use for production high-end Auto Parts and phone parts . OTAI SPECIAL STEEL is Din W-Nr 1.2312 Tool Steel stockholders and suppliers from china. we have more 16 years experience in 1.2312 special tool steel plate, round,  bar, flat bar, square supply.

1.2312 Steel is a high quality plastic tool mold steel . 1.2312 is 1.2311 add about 0.08% Sulphur improve free cutting ability of 1.2311 tool steel . It belong to the high quality medium carbon, Pre-hardness(28~34HRc) plastic mould steel . It needn’t further Make heat treatment for make plasitc injection moulding.
1.2312 tool steel properties is very simliar with ASTM AISI P20S steel . At most work environment,40CrMnMoS8-6/1.2312 steel is equivalent with P20S tool steel .

Related Specifications of Din WN-r 1.2312 tool steel material

Din W-Nr 1.2312 Tool Steel is a nice Plastic Mould steel . we can supply the 1.2312 round bar, steel flat bar, plate, hexagonal steel bar and steel square block . 1.2312 steel Round bar 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 can be supplied, providing a quality precision finished bar to tight tolerances…

1.2312 Sheet Plate  Tool steel is a plastic injection mould steel material . the steel by “super clean” produce 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 very good . can be carried out, and can be processed, suitable for the surface treatment of chrome, material hardness .  good toughness, good mechanical processing performance . Gold microstructure is martensite and bainite structure . Main be applied to in plastic steel mold. like car injection moulding, PVC, PP plastic injection molding etc.

1.2312 tool steel round bar and flat sections can be cut to your required sizes. 1.2312 tool steel ground bar can also be supplied, providing a high quality tool steel precision ground tool steel bar to your required tolerances. 1.2312 steel is also available as Ground Flat Stock / Gauge Plate, in standard and nonstandard sizes.

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Recently a client from Europe sends a quote to us about the Seamless steel tube. So, today I will share some information about the seamless steel tube with you.

Otai company export steel arrange from the alloy steel to tool steel. The seamless steel tube is also included. ASTM A53/ASTM A106/s355/s752/st37 ,etc. If you have a need, you can choose us as your steel provider.

A steel pipe made of a single piece of metal without seams on the surface is called a seamless steel pipe. According to the production method, seamless tubes are divided into hot-rolled tubes, cold-rolled tubes, cold drawn tubes, extruded tubes, and jacked tubes.

Depending on the application, there are thick-walled pipes and thin-walled pipes. Seamless steel pipes are mainly used for petroleum geological drilling pipes, cracking pipes for the petrochemical industry, boiler pipes, bearing pipes, and high-precision structural steel pipes for automobiles, tractors, and aviation.

Classification of Seamless steel tube

Jointless steel pipe along the perimeter of its cross-section. According to different production methods, it is divided into hot-rolled pipe, cold-rolled pipe, cold-drawn pipe, extruded pipe, pipe jack, etc., all have their own process regulations. Materials are ordinary and high-quality carbon structural steel, low alloy steel, alloy steel, stainless acid-resistant steel, etc. According to the purpose, it is divided into two types: general-purpose (for water transmission, gas pipelines and structural parts, mechanical parts) and special purpose (for boilers, geological exploration, bearings, acid resistance, etc.).

Use of Seamless steel tube

• 1 Seamless steel tubes are widely used. General-purpose seamless steel tubes are rolled from ordinary carbon structural steel, low-alloy structural steel or alloy structural steel with the largest output, and are mainly used as pipelines or structural parts for conveying fluids.
• 2 It is divided into three categories according to different uses:
• Supply according to chemical composition and mechanical properties;
• Supply according to mechanical properties;
• Supply according to the hydrostatic test.

3 For steel pipes supplied according to categories a and b, if they are used to withstand liquid pressure, hydraulic tests are also required.

Special-purpose seamless pipes include boiler seamless pipes, chemical and electric power, geological seamless steel pipes and petroleum seamless pipes.

Mr Jack Tan

Tel: 0086-769-23190193

Fax: 0086-769-88705839

Email: jack@otaisteel.com