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OTAI Steel specialized at steel industry over 20 years. OTAI export tool steel to more than 30 countries include Europe, North America, South American, Middle East and Asia. OTAI is stable and reliable tool steel supplier for Fortune 500 companies at home and abroad, such as Thyssenkrupp, China North Industries Group Corporation Limited. OTAI supply tool steel for US oil field giant and one Asia military industry well-known enterprise. OTAI steel materials meet DIN / ASTM / EN / JIS etc different international standards.

OTAI Steel business partner in China

OTAI Steel keep high level tool steel stock, meanwhile have strong sourcing ability in China. OTAI’s main tool steel supplier include Bao steel, Shougang, Valin Steel, Sino Steel, Xingang Steel, SD steel. etc. Most of our material directly from China top 10 worldwide famous steel mill.

Ukraine tool steel supplier story

This customer is professional tool steel supplier in Ukraine. They supply tool steel both Ukraine and other former Soviet states. They work on government bidding project as well. Their purchasing manager Mr Alex sent inquiry about O1 tool steel, AISI 420 stainless steel, and China standard Cr12MoV cold work tool steel half a year before. Mr Alex felt OTAI Steel price was very attractive, and asked samples for inspection. The samples were tested by national laboratory in Ukraine.

One month later, sample test results come out, both chemical composition and mechanical properties data is good. This moment, I have great confidence this company will become our new customer, price is competitive and quality meet their requirement, next step must be a trail order to start our business.

However, Alex sent an email, ask me provide our tool steel supplier name and MTC of original manufacturer, and told me this is their company policy, they could not buy material with “no brand”.

Actually, this is impossible for our company. As a role in the market, both customer and supplier information is commercial secret.

To be continued……

Ms Susie Li

Mobile/WhatsApp: 0086-13826999755

Tel: 0086-769-23190193

Fax: 0086-769-88705839

Email: Susie@otaisteel.com

D2 tooling steel -Chapter 5

CHAPTER 5 OTHER FEATURES

Sometimes features added to a blade for user convenience, like friction grooves on the blade spine, can create stress risers that negate the resistance to blade breakage of zone-edge hardening. Sometimes different production lots of steel exhibit different reactions to zone hardening due to allowable fluctuations in chemical composition. User discretion is the single most predictable way to avoid blade failure from lateral flexing. D2 is probably not the best choice of steel to make sharpened pry bars from, even with zone-edge hardening.

The downside to the nano-grain of the friction-forged edge is it exhibits less “tooth” for reduced cutting efficiency while carving materials like plastic and seasoned wood. Since the first four knives produced by Diamond Blade were primarily hunting knives for processing harvested game, rather than bushcraft, this is probably not a significant issue to Diamond Blade knife users. The knives can cut more meat and hide between sharpening, as only the “best of the best” can.

BUSHCRAFT AND UTILITY KNIVES

For bushcraft and utility applications, I would choose a D2-bladed Knives of Alaska model from this sister company which is also run by Diamond Blade’s managing partner Charlie Allen. The KOA D2 blades are conventionally heat treated, double-draw tempered and cryo-treated for remarkable performance in their own right. They just don’t match the Diamond Blade for overall cutting endurance between sharpening.

Yet another way to produce knife blades out of D2 steel alloy is by casting the blade blank out of molten D2 steel. The blank is then finish-ground and heat treated to individual specifications. Selected handle materials help to create each cast blade into a distinctively individualized knife.

Cast D2 is sometimes called Dendritic D2. The proponents of this production method believe the steel grain of the blade has more predictable properties from casting, then what can be attained with other methods. They claims to have more consistent carbide structure at the blade edge and longer cutting endurance. Of course edging, alloy content and final heat treatment still play a dominant role in determining the performance of each finished knife, regardless of steel production or blade-creation methodologies.

D2 is not an alloy used for forged knives with any frequency. The steel is difficult to move with a hammer and prone to decarburizing when it’s heated high enough for easier metal movement. D2 is occasionally incorporated into Damascus blades, but there have been problems with some D2 Damascus experiencing de-lamination of the layers under lateral stress.

WhatsApp: +86-769-23190193

Tel: +86-769-23190193

Fax: +86-769-88705839

Email: Jack@otaisteel.com

AISI 4140 stock promotion from Otai Special Steel . Annealed , Black surface original board , T45 / 95 / 100 *W2250*L5000-12000MM , T19 / 31*W2230*LMM , T39*W2260*LMM , Total weights : 50Tons , limited stock for sales promotion in one week , the price RMB1800.00 Yuan less than before per ton , very competitive cargoes , end of sales .

AISI 4140 stock promotion . AISI 4140 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 . AISI 4140 Annealing delivery hardenss less than 250HB .

AISI 4140 stock promotion . AISI 4140 Alloy steel material stockholders and suppliers from China-OTAI SPECIAL STEEL . we have more 16 years experience in 4140 steel plate, round bar, flat bar, square supply.AISI 4140 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 .

Chemical Properties
The table below highlights the chemical composition of AISI 4140:

C                      Cr                        Mn                 Si                   Mo                   S
0.38-.43%      0.80-1.10%     0.75-1.0%    0.15-0.30%    0.15-0.25%   0.040%

P                          Fe

max 0.035%     max Balance
The addition of chromium and molybdenum promotes corrosion resistance. The molybdenum can be particularly useful when trying to resist corrosion due to chlorides. The manganese in AISI 4140 is used to increase hardenability and as a deoxidizer. In alloy steels, manganese can also combine with sulfur to improve machinability and make the carburizing process more effective.

AISI 4140 stock promotion . AISI 4140 steel round bar and flat sections can be cut to your required sizes. ASTM 4140 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 .

Ms Monica Yu

Mobile/WhatsApp: 0086-13711903397

Tel: 0086-769-23190193

Fax: 0086-769-88705839

Email: Monica@otaisteel.com

A2 tool steel is an air-hardening, cold work steel. A2 is a 5% Chromium steel which provides high hardness after heat treatment with good dimensional stability.

Do you know about A2 tool steel? There are many common used steel in our company, like 4140,8620,etc.maybe you are not familiar with a2 steel, A2 Tool Steel is a versatile, air hardening chromium alloy tool steel that replaces O1 tool steel when safer hardening, less distortion and increased wear resistance are required.

 A2 tool steel is an air-hardening, cold work steel. A2 is a 5% Chromium steel which provides high hardness after heat treatment with good dimensional stability. It is heat treatable and will offer a hardness in the range 57-62 HRC.

Our otai company can supply the a2 steel, we have a customer who is knife stockist in Asia, they produce the different knives made of steel, but the knife made of a2 steel is most appreciated, he purchased the a2 steel from our company every year. We paid a visit with the customer in September, we knew most people bought the knife for wood carving, food preparation, cleaning fish and possibly wilderness survival.

Characteristics of A2 tool steel 

1good machinability,

2high compressive strength,

3high dimensional stability after hardening and tempering.

4Good hardenability, very good non-deforming properties, deep hardening,

5Good wear resistance, AISI A2 tool steel takes a place between AISI O1 and AISI D2, offering an excellent combination of good wear resistance and toughness. 

Applications 

Typical Applications for  A2 tool steels materials: Blanking dies, block and ring gauges, coining, cold forming, cold trimming and forming dies, cold shears, rolls, knurls and knurling tools, machine parts, mandrels, punches and punch plates, reamers, shear, and slitter blades, stamping dies and threading tapes.

Company History

Otai Steel supplies a wide range of carbon, alloy, and stainless 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, stockist and exporter. Combined with the experienced exporting team and professional technical knowledge, Otai Steel offers both technical advice and support, as well as global professional steel solution and service.

Mr Jack Tan

Tel: 0086-769-23190193

Fax: 0086-769-88705839

Email: jack@otaisteel.com

In mold steel business, you know what kind of customers are right for you. If you find yourself unsuitable, you can reject it frankly.

In mold steel business, you know what kind of customers are right for you. If you find yourself unsuitable, you can reject it frankly.

one of the fortune 500 companies contacted us, They wanted to find a company that could provide the mold steel for common requirements, and also accepted a long payment time.

In the past, I would try to cater to customers,a opportunities for cooperation with large companies,most people must fight hard for this chance. Now I think that the type of required by their company does not match our superior products. Terms of payment are even more unacceptable.

First of all, our target customers are who have requirements for the quality mold steel, not all mold manufacturing enterprises. we focus on 8 type mold steel products to meet a small number of customer needs. Such as:

• H13,which meets the long-life aluminum die-casting mold.it perfect

For the aluminum extrusion factory, metal extrusion molds that can be used longer.

• 2738,higher quality plasticmold steel
• 4140for some auto industry.

In my opinion, there are thousands&thousands of customers demand mold steel ， and there is no need to deliberately force a certain customer. If it’s not fit for you, no matter how big the company is, it doesn’t matter to me. Meeting a small number of customer needs is enough for me to live comfortably. It is not necessary to change the company’s positioning for a certain customer.

If you want to know more about H13,1.2738,4140,please contact me,I am sure there must something I could help with,as I had work in Otai special steell company  3years,and this company have 20 years experience of mold steel & tool steel. Otai special steel start with domestic mold steel & tool steel business since 1999,and we have solve many problem for our customer,no matter 4140 tool steel or H13 hardware extrusion mold steel or 1.2738 plastic mold steel,we sure will offer a suitable one for you.

Ms Sharon Wan

Mobile/WhatsApp: 0086-13580960968

Tel: 0086-769-23190193

Fax: 0086-769-88705839

Email: Sharon@otaisteel.com

CHAPTER 4 MARTENSITIC STEELS

CHAPTER 4 MARTENSITIC STEELS

Martensitic steels get harder when they are heated above a certain temperature (usually 1,600°F or higher) and then rapidly cooled or quenched. The exact temperature the steel is heated to, how long it is held at that temperature and how rapidly it is quenched is called heat-treating. Tempering occurs by heating the steel to lower temperatures (like 400 to 600°F) to gradually soften the steel so it will be less brittle.

The actual range of cutting performance exhibited by different D2-bladed knives is wide enough to make one doubt that the same steel is in use. Without actually testing the knives, you’ll never know what they can do and whether you want it done that way.

WHAT ABOUT POWDERED PROCESS STEEL?

Powdered process steel is a more costly method of steel production. First, melted steel alloy is sprayed through an atomizer nozzle to form tiny droplets of fine steel powder. The steel powder is loaded into a molding chamber where tons of pressure (and sometimes heat) is applied to fuse the powdered particles back into a solid steel billet (or in some cases, into a molded shape as a steel part). The theoretical advantage powdered process steel has for knife blades is the resulting steel billet is finer-grained with a more even carbide distribution than a poured and rolled steel plate may provide. Knife blades made from powdered process steel are often touted as being more chip- and break-resistant as a result.

There has been, and continues to be, debate about how clean the steel produced by powdered process is expected to be. Some prominent knifemakers candidly told me that many lots of powdered production steel couldn’t be mirror-polished without revealing inclusions that look like scratches or blemishes in the steel. Production of blades with bead-blasted finishes or finishing coatings makes this issue of less relevance to the consumer, but it remains a concern to some knifemakers who question whether the structural integrity of the steel is consistent. The powdered process CPM D2-bladed knives I’ve tested from commercial and custom sources have proven to be a delight to use for every day cutting purposes.

BREAK TESTING

D2 knife blade breakage-resistance depends largely on blade thickness and heat treatment, according to the doctor of D2, Bob Dozier. Thicker blades with higher Rockwell hardness ratings will have less elastic stretch.

When deliberately break-testing the blade of a Queen Razor Blade Trapper model with D2 steel blades, I was once able to bow the 0.095-inch-thick RC57 Razor Blade more than a full 90° bend, before forcing it to snap. I was startled by the ability of this knife’s D2 blade to be able to endure so much lateral stress. Most normal users wouldn’t have continued to push the blade past its failure point, since it exhibited so much spring-like flex. This blade predictably performed as a rope cutter on the low end of D2 range, but it was very easy to sharpen.

Readers need to keep in perspective that its cutting endurance was still on the high end of “good,” therefore exceeding what half of all knives deliver in comparable testing.

Queen Cutlery makes traditional-style folders with D2 blades in a variety of patterns.

When it comes to producing D2-bladed knives with more potential resistance to breakage in thicker blade stocks, the new Friction Forged D2 Diamond Blade Knives might have a theoretical advantage. Friction Forging results in a blade with a zone-hardened edge (Rockwell hardness 66-68) for extraordinary cutting endurance supported by a much softer steel back. The soft, spring-like steel back can (in some cases) be flexed to over 90° without breakage. The friction-forged edge has a nano-grain carbide structure so fine that it may not be as prone to cracking and tearing as it is flexed.

WhatsApp: +86-769-23190193

Tel: +86-769-23190193

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Email: Jack@otaisteel.com

aisi 1020 steel is a low hardenability and low tensile carbon steel. This standard has high machinability, high ductility, high strength, and good weldability. otai is expert on the 1020.

Recently, I received an inquiry from a company comes from Singapore, it provides services in the field of manufacturing which specializes in the fabrication of jigs, fixtures, and turned parts for the Electronic Industry. He wants to buy the aisi 1020 steel used as the fixture, but he never import 1020 from china before, so he asked me a lot of questions about the standard, the quality and the delivery time.

I told him that we had exported aisi 1020 steel to many counties, we have more than 16 years’ experience in special steel supply, we don’t want to talk about the quality only with words, the facts count, many customers repeat arrange the order every year. finally, he bought aisi 1020 steel, I’m sure he will be satisfied with our product.

aisi 1020 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. The product is on the stock.

application of 1020 steel

aisi 1020 steel is a low hardenability and low tensile carbon steel. This standard has high machinability, high ductility, high strength, and good weldability. Due to its low carbon content, it is resistant to the induction hardening or flame hardening and lack of alloying elements, it will not respond to nitriding. Although, carburization is possible to obtain case hardness more than Rc65 for smaller sections, which reduces with an increase in section size. Core strength will remain as it has been supplied for all the sections.

aisi 1020 steel is suitable for making cars, tractors and general machinery small and medium-sized carburizing and carbonitriding and other parts, such as car hand brake shoe, fork lever shaft, transmission speed, transmission driven gear and the tractor on the camshaft, hanging equalizer axle, equalizer, inner and outer bushing, etc. In the condition of hot rolling or normalizing used in the manufacture of force is not big, but all kinds of high toughness requirement of mechanical parts;

aisi 1020 steel also applies in medium and heavy machinery industry, such as forging or suppression of rod, shackle, leverage, sleeve, fixture, etc. In steam turbine and boiler manufacturing for more pressure or less 6N/㎡, the temperature of 450 ℃ or less corrupt media work of pipes, flanges, header, and various kinds of fasteners; On the railway and locomotive vehicles used in the manufacture of the crosshead and piston castings.

Introduction of otai

Otai Steel supplies a wide range of carbon, alloy, and stainless 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. 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.

Mr Jack Tan

Tel: 0086-769-23190193

Fax: 0086-769-88705839

Email: jack@otaisteel.com

T10 Steel Stock in China from Otai Special Steel .

What is T10 Steel ? T10 carbon tool steel has higher strength and abrasion resistance than T8 and T9, but has low thermal rigidity, low hardenability and large quenching deformation, and fine grains. It is not easy to overheat during quenching and heating, and can still maintain fine grains. Microstructure; there are undissolved excess carbides in the steel after quenching, so it has high wear resistance, Otai Special Steel have stock with T10 and is used to make tools with sharp edges and a little toughness. It is suitable for manufacturing various tools with poor cutting conditions, high wear resistance, and resistance to sudden and severe shock vibration, which requires certain toughness and sharp edges, and can also be used as wear-resistant parts that are not subject to large impacts .

T10 Steel Stock in China from Otai Special Steel .

With regards to t10 steel, the T, in this case, signifies that it’s a High-Speed steel with a Tungsten Base. High-Speed tool steels include tungsten (t1 to t15) and the molybdenum (M1 to M52) steel alloys. These allow are characterized by their ability to be hardened to 62 to 67 HRC. while maintaining this hardness through significant temperature ranges, up to 1004°F, which means they are particularly well suited to high-speed machinery (hence the name). These steel alloys are commonly employed in drills, lathes, routers, and saws. The 10 in T10 signifies the carbon content, which ranges between 0.95% and 1.05%. The T types of steel start at T1` which is between 0.05% and 0.15% carbon content, all the way up to T15 which typically has a carbon content of between 1.2% and 1.3%.

T10 Steel Stock in China from Otai Special Steel .
T10 steel is perhaps one of the strongest and most suitable carbon steels that we are easily able to obtain for knife tool use. Its characteristics and properties are not only suitable for tools, but it can create a superb knife tool as well.

Ms Monica Yu

Mobile/WhatsApp: 0086-13711903397

Tel: 0086-769-23190193

Fax: 0086-769-88705839

Email: Monica@otaisteel.com

A friend asked me: How long will your die steel last for the aluminum alloy die-casting mold？Actually, this question is really difficult to answer

Die steel 

A friend asked me: How long will your die steel last for the aluminum alloy die-casting mold？

Actually, this question is really difficult to answer.

Because some customers use our sulfur-free 8407 mold steel for aluminum alloy die-casting molds. 280,000 molds have been produced, and molds are still being used.

It is such a real case that we dare not promise to the customer in writing, because the using time of die steel for aluminum alloy die-casting molds is related to many factors. Such as: mold steel purity, mold structure complexity, mold size, mold design, heat treatment process, pre-hardening degree during use, cooling method during use, mold release agent, stress relief after use, etc … these are all could effect the mold life.

The real market situation is that many aluminum alloy die-casting molds have problems, which directly make the mold steel suppliers back. Hope everyone can understand the pain of mold steel man.

If you would like to know more about die steel for aluminum alloy die-casting molds ,pleasae see below of click the link –Die steel.

1. AISI H13 tool steel Chemical composition

2. Applications of AISI H13 Tool Steel

H-13 Tool Steel is used in hot forging dies, hot forging die inserts, hot gripper dies, hot nut tools, hot header dies, brass forging and pressing dies, hot forging aluminum base dies, aluminum casting and extrusion dies, zinc die casting dies, extrusion mandrels, plastic molds, cores, die holder blocks, hot press dies, hot work punches, etc.

3. AISI H13 Steel Forging

For forging H13 tool steel, first slowly Preheat to 750°C(1382°F), soak enough time, then rapidly heat to 1050-1100 °C(1922-2030°F). then start forging, ensure the forging temperature higher than 850°C(1562°F).  Cool H13 tool steel must be slowly after H13 steel forging finished.

4. Annealing of Tool Steel H13

Heat to 840-860°C(1544-1580°F), Soak thoroughly before furnace cool at a maximum rate of 20°C(68°F) / hour, Cool down to 600°C (1112°F). Then cool in air.

5. Stress Relieving

Befor make products, The Tool steel stress relieving is very necessary.  When H13 tool steel is ground , heavily machined, cutting,milled , the relief of internal strains is necessary before hardening to minimise the possibility of distortion. for stress relieving, heat the H13 steel component to 700°C(1292°F) carefully, Get  enough soaking period . Then cool in the furnace or cool in air.

6. Hardening

first should preheat the H13 tool steel parts to 780-820°C(1436-1508°F), Soak enough time, ensure soak thoroughly. then rapidly heat to 1000-1030°C(1832-1886°F), soak about 30 mins. cool in air or oil.

Ms Sharon Wan

Mobile/WhatsApp: 0086-13580960968

Tel: 0086-769-23190193

Fax: 0086-769-88705839

Email: Sharon@otaisteel.com

D2 Tool Steel-chapter 3

DON’T JUDGE D2 STEEL BY ITS LOOKS

DON’T JUDGE D2 STEEL BY ITS LOOKS 

You can’t tell how a knife cuts just by looking at it — you have to cut something with it. I perform cutting tests in materials that have proven to be hard to cut for all but the very best knives. I also do side-by-side cutting comparisons while doing daily cutting chores to distinguish which knives cut with the fewest limitations.

For instance, the D2 knives that made the fewest cuts on rope using only 1-inch of blade, and comparable edge geometry, still accomplished enough slices to be on the high end of “good” by my evaluation criterion. The longest-cutting knives will cut 10 times longer between sharpening, than the knives with the least cutting endurance.

I can take the two very best D2-bladed rope cutters I’ve tested and compare them by cutting the neck off a plastic bottle. One blade can accomplish this with a single slice; the other blade requires 15 slices. In this case, the different heat-treatments achieve different carbide grain sizes, and the larger carbide grain apparently cuts this plastic better than the nano-grain carbide, which is 10 times smaller.

SO, WHAT KIND OF KNIFE DOES D2 STEEL MAKE?

It varies from good to extraordinary, depending on the production lot of steel, the way the steel is heat-treated, and the way the blade edge is beveled and finished. The knife owner can control the last two variables, but the others are established invisibly before the knife is purchased.

The only way to know how good your knife is, is to test it with repeatable cutting tests. It’s like accuracy-testing a firearm. Experience may indicate that a certain type of gun usually performs well. However, the way it performs can depend on the ammo used, and preferences will vary from individual gun to individual gun.

The D2 knives that cut the longest in rope may not always cut the best in other materials. Quantity of cut and quality of cut are usually, but not always, coincidental. The only way to find out is to cut with your knife and test its capabilities. You can at least then be either satisfied or disappointed enough to stay with what you’ve got, or try something different.

Chances are good you’ll ultimately need more than one knife to accomplish all your cutting chores with the least applied effort. But you can’t tell  — without comparison-cutting with different knives on the same tasks  — which knife is the easiest to use for that task.

Every knife has the potential to be a unique performer in your hands, no matter what any authority tells you to expect on the basis of their experience. Test your own knife, and you become the definitive authority on the knife in your hand. The same conditions apply to every knife with any martensitic steel alloy used for knives.

WhatsApp: +86-769-23190193

Tel: +86-769-23190193

Fax: +86-769-88705839

Email: Jack@otaisteel.com