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High Speed Steel –M2 Part 2

M2 high-speed steel is a tungsten-molybdenum tool steel. M2 is characterised by well-balanced toughness, wear resistance and red hardness properties.

AISI M2 high-speed steel has largely replaced T1 in most applications due to its superior properties and advantageous pricing. M2 is medium-alloyed and is a good all-round performer with good machinability, in this respect it is superior to the high alloyed cold work steels.

Related Specifications : DIN 1.3343

Applications

The well balance properties of M2 means it is used in a wide range of cutting tools where demands for hot hardness are moderate, such as twist drills, reamers, broaching tools, milling tools, taps and metal saws.

M2 is also suitable for cold work applications such as tools for punching, forming and pressing.

If you are looking for superior red-hardness then consider M42 high speed steel.

M2 high-speed steel stock

Steel Express stock and supply M2 high-speed steel in round, flat and square bar. We can cut to your requirements in house.

M2 diameters from 10 mm up to 250 mm. Flat and square stock, please call with your requirements .

Heat treatment of M2 high-speed steel

The following information is provided for guidance only. The rate of heating, cooling and soaking times will vary due to the shape and size of each component and other external factors.

Annealing

Heat the M2 high-speed steel to 850 – 900°C. Hold at temperature for at least two hours or one hour per 25 mm of thickness. Furnace cool slowly. The maximum hardness should be 248 Brinell.

Stress relieving

Stress relieving M2 is recommended after machining or grinding and before hardening to minimise the chance of distortion. Heat the component to 600 – 700°C and soak well (for approximately two hours), then cool in air.

Hardening

Pre heat the M2 in two steps; 450 – 500°C then 850 – 900°C. Then continue heating to the final hardening temperature of 1200 – 1250°C. Do not leave the steel too long at the hardening temperature. Quench in warm oil or brine to about 500°C then air cool down to room temperature.

Tempering

Heat the M2 to the required tempering temperature, hold at temperature for at least two hours or one hour per 25 mm of thickness. Double tempering is recommended.

Forging

Pre heat slowly to 850 – 900°C, then increase more quickly to the forging temperature of 1050 – 1150°C. Do not forge below 880 – 900°C. Cool very slowly after forging.

(data sheet & typical analysis available on request).

Properties

M-2 is typically bought to meet chemistry requirements rather than physical requirements. For that reason, physical properties are generally not provided unless requested prior to production. Any material can be sent to a third party after production to be tested for physical properties.

Typical Uses

Typical Applications include Broaches, Boring Tools, Chasers, Cold Forming Rolls, Cold Heading Inserts, Drills, End Mills, Form Tools, Hobs, Lathe and Planer Tools, Punches, Milling Cutters, Taps, Reamers, and Saws.

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High Speed Steel –M2 Part 1

High Speed Steel –M2 Part 1

High-speed steel (HSS or HS) is a subset of tool steels, commonly used as cutting tool material.

It is often used in power-saw blades and drill bits. It is superior to the older high-carbon steel tools used extensively through the 1940s in that it can withstand higher temperatures without losing its temper (hardness). This property allows HSS to cut faster than high carbon steel, hence the name high-speed steel. At room temperature, in their generally recommended heat treatment, HSS grades generally display high hardness (above Rockwell hardness 60) and abrasion resistance (generally linked to tungsten and vanadium content often used in HSS) compared with common carbon and tool steels.

M2

M2 is the “standard” and most widely used industrial HSS. It has small and evenly distributed carbides giving high wear resistance, though its decarburization sensitivity is a little bit high. After heat treatment, its hardness is the same as T1, but its bending strength can reach 4700 MPa, and its toughness and thermo-plasticity are higher than T1 by 50%. It is usually used to manufacture a variety of tools, such as drill bits, taps and reamers. 1.3343 is the equivalent numeric designation for M2 material identified in ISO 4957.

Lasers and electron beams can be used as sources of intense heat at the surface for heat treatment, remelting (glazing), and compositional modification. It is possible to achieve different molten pool shapes and temperatures, as well as cooling rates ranging from 10³ to 10⁶ K s⁻¹. Beneficially, there is little or no cracking or porosity formation.^[1]

While the possibilities of heat treating at the surface should be readily apparent, the other applications beg some explanation. At cooling rates in excess of 10⁶ K s⁻¹ eutectic microconstituents disappear and there is extreme segregation of substitutional alloying elements. This has the effect of providing the benefits of a glazed part without the associated run-in wear damage.^[1]

The alloy composition of a part or tool can also be changed to form a high speed steel on the surface of a lean alloy or to form an alloy or carbide enriched layer on the surface of a high speed steel part. Several methods can be used such as foils, pack boronising, plasma spray powders, powder cored strips, inert gas blow feeders, etc. Although this method has been reported to be both beneficial and stable, it has yet to see widespread commercial use.^[1]

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16MnCr5 alloy steel, Otai provides a specific size for you.

Today let’s talk about 16MnCr5 alloy steel, it is geared steel, we will receive several quotes from our clients every year. Although it is not the main product of our company, I’d like to share the basic information with you. If you are considering to buy it, maybe you can know more about the 16MnCr5 alloy steel from this article.

16MnCr5 gear steel is a steel grade imported from Germany, which is equivalent to China’s 15CrMn steel, but its mechanical properties are better than 15CrMn steel. It has better hardenability and machinability. For larger cross-section parts, a higher surface can be obtained after heat treatment.

16MnCr5 is a carburized steel, which is usually low carbon steel with a carbon content of 0.17% to 0.24%. Most of the transmission gears used in automobiles are medium-hardenability carburizing steels, which have high hardenability. Under the condition of ensuring hardening, especially with high low-temperature impact toughness. 16MnCrS is suitable for surface carburizing and hardening treatment. , Has good processability, processing distortion is small, fatigue resistance is quite good.

Chemical of 16MnCr5 alloy steel:

C: 0.14~0.19%

Si: 0.15~0.40%

Mn: 1.00~ 1.30%

Cr: 0.80~1.10%

S:≤0.035%

P:≤0.035%

Form of Supply

DIN 16MnCr5|1.7131 gearing steel, otai company can supply the round bar, steel flat bar, plate, hexagonal steel bar, and steel square block. DIN 16MnCr5|1.7131 steel Round bar can be sawn to your required lengths as one-offs or multiple cut pieces. 16MnCr5|1.7131 gearing steel Rectangular pieces can be sawn from flat bar or plate to your specific sizes. Ground tool steel bar can be supplied, provide a quality precision finished bar to tight tolerances.

Application of 16MnCr5 alloy steel

16MnCr5 is good carburizing steel with high hardenability. After carburizing and quenching, it has a hard and wear-resistant surface and a tough heart. It has high low-temperature impact toughness, medium weldability, and can be cut after normalizing. Sex is good.

16MnCr5 is used to manufacture important parts with a cross-section <30mm, which can withstand high speed, medium or heavy load, impact, and friction, such as gears, ring gears, gear shaft crossheads, etc. Can be used as 15CrNi6 substitute steel, widely used as carburizing parts, in the automobile, aircraft and tractor industry for cross-section below 30mm, withstand high speed, medium speed or heavy load and impact, friction important carburizing parts, such as gears, Shafts, ring gears, gear shafts, main shafts of sliding bearings, crossheads, claw clutches, worms, etc.

Mr Jack Tan

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42CrMo Round Bar peeled for produce Bolt and Screw . As now in China the coronavirus have controlled already , and everything was very well as before . But the other countrys on abroad  confirmed case of coronavirus infection one after other . Hope all people on the world could Defeating the epidemic . And our working could resume like before . Any new inquiry about 42CrMo4 and AISI 4140 , please contact with us as soon as possible .

42CrMo Round Bar peeled for produce Bolt and Screw provided by Dongguan  OTAI Special Steel Limited .

We have more 16 years experience in 42CrMo steel plate, round bar, flat bar, square supply . 42CrMo 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 AISI 4140 alloy steel.

42CrMo alloy steel material 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 .

 AISI 4140 equivalent material

• ♦JAPAN♦ : JIS SCM440 alloy steel
• ♦GERMANY♦ : DIN WN-r 1.7255 / 42CrMo4 steel alloy
• ♦CHINA♦ :  GB 42CrMo steel
• ♦BRITISH♦ : BS 708M40
• 42CrMo Tool steel is a alloy structural steel . 42CrMo Round Bar peeled is used for engineering structural .like high tensile shafts, bolts and nuts, gears, pinions and spindles. Locomotive traction with the big gear. supercharger drive gear, pressure vessel, rear axle, gear load of connecting rod and a spring clip.4140 can also be used to under 2000 m deep well of oil drill pipe joint and the fishing tool. and can be used for bending machine mould, etc

42CrMo Round Bar peeled and flat sections can be cut to your required sizes.  42CrMo  tool steel ground bar can also be supplied, providing a high quality tool steel precision ground tool steel bar to your required tolerances. SAE 4140 steel is also available as Ground Flat Stock / Gauge Plate, in standard and nonstandard sizes.

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H-21 hot work tool steel, otai will satisfy your demand.

Maybe you heard a lot about hot work tool steel.However, do you know about the h21? H-21 hot work tool steel is perhaps the most widely used of the Tungsten steels. it belongs to the high-quality high carbon alloy tool steel.  The 9.5% tungsten content imparts good resistance to softening at service temperatures while still maintaining adequate toughness.

Recently, several clients from Italy ask me whether otai company can provide h21 steel for them, of course, the answer is positive. We sold the h21 steel. They want to import the h21 steel from our company,  they build springs, shaped parts and precision metal parts of all types and shapes, in particular for applications in the automotive, motorcycle, household appliances, and industrial plant engineering fields. While h21 is suitable steel for them.

Unlike the higher tungsten grades, H-21 may be cooled by the continuous flow of water if the design of the die will permit. Oil Quenched & Tempered Hardness is 28-34 HRc. AISI H21 steel Annealing delivery hardness less than 250HB.

Chemical Composition

Carbon 0.35

Manganese 0.25

Silicon 0.35

Chromium 3.50

Tungsten 9.50

Vanadium 0.50

 Main Application

H21 hot work tool steel is particularly useful for hot forging and blanking dies and punches for making nuts, bolts, and other similar small components. Dies, cores, inserts, pins, etc for the die casting of copper-base alloys are also prime applications for this steel. Other uses include forming dies, shear blades, hot extrusion dies, mandrels, punches, die, holders, ejector discs and extrusion lines.

Due to satisfactory reliable quality and professional service, Otai expands our market worldwide.such as UAE, Canada, Brazil, Colombia, Chile, Spain, Turkey, Algeria, Vietnam, Malaysia and so on. If you are ready to buy tool steel or carbon steel, please choose otai company, you will not regret it.Maybe you heard a lot about hot work tool steel,h13 is widely used tool steel. However, do you know about the h21? H-21 is perhaps the most widely used of the Tungsten hot work steels, it belongs to the high-quality high carbon alloy tool steel.  The 9.5% tungsten content imparts good resistance to softening at service temperatures while still maintaining adequate toughness.

Recently, several clients from Italy ask me whether otai company can provide h21 steel for them. of course, the answer is positive. We sold the h21 steel. They want to import the h21 steel from our company,  they build springs, shaped parts and precision metal parts of all types and shapes, in particular for applications in the automotive, motorcycle, household appliances, and industrial plant engineering fields. While h21 is suitable steel for them.

Mr Jack Tan

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H13 STEEL APPLICATION IN LIFE-Chapter 13

After FSLW experiments for H13 steel , samples were taken for tensile-shear testing and for metallography. Tensile-shear test samples and supporting pieces were 16 mm wide. Details of gripping a sample for testing, which is commonly used for testing lap joints, have been explained [11]. Samples were tested at a constant crosshead displacement rate of 3 mm/min using a 50 kN Tinus Olsen tensile machine. The strength of a lap sample cannot be expressed using the normal load/area expression, as the stress distribution along the joint area is highly uneven. Instead, maximum load in a test divided by the sample width, F_m/w_s, is taken as joint strength. For microstructure observation using optical microscope and SEM, the welds were cross-sectioned, mounted and polished following the normal metallographic procedure.

Advanced Characterization Techniques for Nanostructures

Jiménez et al. recently investigated a plasma-assisted physical vapour deposition technique to grow (TiAl)N films on H13 tool steel¹⁴. This tool steel is commonly used as a forming dye material at temperatures up to 600°C. Above this temperature the surface oxidizes and spalls quickly. In order to enable this tool material to be used at higher temperatures, a protective surface coating is needed. Thermal treatment of the H13 tool steel with and without (TiAl)N coatings were investigated with an AFM used in non-contact mode. Uncoated substrates showed appreciable increase in surface roughness due to oxidation at temperatures above 600°C whereas coated samples retained similar surface profiles after temperature treatments up to 1000°C (see Figure 3.4). X-ray diffraction (XRD) measurements were used to confirm and correlate these topographical measurements with the surface reactions. Extensions of the AFM, force modulation microscopy (FMM) and phase detection microscopy (PDM) were also used to image the surface. In FMM mode the tip is scanned in contact with the sample while a displacement sinusoid of a few kilohertz is applied to the tip or sample. The applied amplitude signal is modulated according to the elastic properties of the sample. FMM can therefore be used to image hard and soft regions at the same time as topological information is recorded. PDM is used when the AFM is operated in intermittent contact mode. PDM refers to the monitoring of the phase lag between an applied signal driving cantilever oscillation and the cantilever oscillation output signal. Changes in the phase lag reflect changes in the mechanical properties of the sample surface.

Tanaka et al. investigated the effect of toner particle morphology on toner fluidity and adhesion strength using an AFM¹⁵. Particle fluidity and interactions are influenced by surface structure size and morphology as well as the particle size and morphology. A fractal dimension was used to quantify the particle surface shape, which was related to its flow properties, and particle adhesion forces, which were measured with an AFM. The fractal dimensions were directly scaled from the nanostructure on the toner particle surfaces. A toner particle of approximately 5.5 μm diameter was attached to the AFM tip (see Figure 3.5), which was then held close to compacted toner powder (with a pressure of 54.9 MPa). The force to move the tip/particle away from the surface was recorded. Toner particles were nanotextured to various degrees by mixing with fine SiO₂ particles (mean diameter of 20 nm) which adhered to the toner particles. As the fractal dimension increased, the shearing and adhesion force between particles was also seen to increase.

Matějka et al. examined the wear characteristics of SiC-reinforced iron-phenolic based brake disks using an AFM¹⁶. Abrasives, such as SiC, are added to brake disk composites in order to increase the friction coefficient and stabilize it at higher temperatures. At temperatures above 250°C an enhanced pull-out of SiC was noted from the AFM results. The AFM results also showed that these particles could help maintain the friction coefficient at higher temperature due to their abrasion of the disk surface. A potential drawback of quicker abrasion of the contact surface was also reported. An optimum of approximately 3.4% SiC addition was determined from this work.

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The brief of H13 STEEL

The brief of h13 steel

H13 is a hot work tool steel that has good resistance to thermal fatigue, erosion and wears, and is widely used for making molds and dies. The H13 powder used for laser consolidation contains 0.42% C, 5.04% Cr, 1.33% Mo, 1.06% V, and 0.88% Si. LC H13 samples were metallurgically sound and free of cracks or porosity. LC H13 tool steel showed a directionally solidified dendritic microstructure with layered features: very fine columnar dendrites (around 1–2 μm in dendritic arm spacing) aligned along the vertical direction (Fig. 16.4A). Cellular features were observed along the transverse cross-section.

The XRD results indicated that the LC H13 steel consisted of a majority of α (martensite) plus a trace amount of γ phase (Fig. 16.4C), which was very similar to the H13 powder used for the consolidation except for the reduced amount of γ phase. Further XRD analysis indicated that the carbides extracted from the LC H13 material were of MC, M₇C₃, and possible M₃C types.

the properties of h13 steel

The LC H13 tool steel showed excellent tensile properties (Table 16.2). The average yield and tensile strengths of the consolidated H13 along the vertical direction were about 1288 and 2064 MPa, respectively, while the elongation was about 6% and the elastic modulus was about 216 GPa. Along the horizontal direction, the LC H13 showed significantly higher yield strength (1564 MPa) than along the vertical direction. while the tensile strength, elastic modulus, and elongation of LC H13 were comparable for both directions.

It should be noted that the tensile properties of the LC H13 material had relatively small scatter. For example, along the vertical direction, the standard deviations of the yield strength and tensile strength were about 54 and 51 MPa, respectively, while the standard deviations of the elastic modulus and elongation were 4 GPa and 2.2%, respectively, which indicated that the laser consolidated H13 material at a reasonably good consistency.

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H13 STEEL APPLICATION IN LIFE-Chapter 9

Like all dies, however, H13 steel  is regrettable that they are not really permanent. An aluminum casting weighing up to 1 kg might be produced tolerably well for up to 80 000 or 100 000 shots before the die will require to be refurbished as a result of heat checking (cracks due to thermal fatigue of the die surface that produce a network of unsightly raised fins on the cast surface of H13 Steel).

Magnesium alloy high-pressure die castings  of H13 steel are much kinder to dies, giving perhaps five times or more life. This is partly the result for H13 steel the lower heat content of Mg alloys, and partly because of the low solubility of iron in liquid magnesium that reduces its action to dissolve the die surface. In contrast, liquid Al has a relatively high solubility of iron, resulting in a phenomenon known as ‘soldering’ of the casting to the die. This action is particularly destructive to dies. It is countered to some extent by the addition of high levels of iron to high-pressure die-casting alloys, thus pre-saturating the liquid metal with iron and so greatly reducing the tendency for the melt  of H13 steel to dissolve the die.

Attempts have been made to cast  of H13 steel molten stainless steels by high-pressure die casting. In this case  of H13 steel the only die material of H13 steel capable of withstanding the rigors of this process was an alloy of molybdenum. Even these ‘moly’ dies suffered early degradation by thermal fatigue cracking, threatening the commercial viability of the process. So far as the author is aware, partially solid (inaccurately called ‘semi-solid’) stainless steels have not been extensively trialed. These cooler mixtures that have already given up practically half of their latent and specific heat during freezing would greatly benefit die life. The commercial viability of the somewhat more expensive mixture would remain a potential show-stopper of course for H13 steel .

Because of the very high pressures for H13 steel  involved in HPDC internal cavities are usually limited to those formable by straight withdrawable steel cores. If the core cannot be withdrawn then the usual alternatives such as sand cores are totally unsuitable because they are penetrated by the liquid metal. One of the H13 steel is very few options to make undrawable cavities in HPDCs are salt cores described below.

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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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