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h13-die steel application –chapter 10

H13  -heat treatment are decarburization, superheating, And H13  also make the mold surface gets residual tensile stress. That H13 will make the mold get failure early. If the temperature of some parts of grinding surface up to over 800℃, and not make it cool fully. Then the material of the surface layer of  H13 will be re-austenize.

1. And quenching into martensite. So H13 the surface layer of the die will get high stress. At the same time,H13 will make the possibility of getting grinding crack be higher. The technology of heat treatment .
2. Taking the heat treatment in the right way will make the mold get what it needs about the properties and raise the time of working. But if do H13 in the wrong way, H13 will cause the defects of heat treatment. H13 will harm hugely to its load capacity. The defects of H13 will be dehiscence, strength is not enough and etc.
3. After a period of time of use, the internal stress accumulates to a damage level. H13  must do a work of strain relief tempering. If not, H13  will dehiscence during work time.

The use and care of h13-die steel

The preheat of steel moldH13 steel has high content alloy elements and its thermal conductivity is bad. So it must fully preheat before the use. The temperature of preheating too high, then the temperature of the mold will be higher during the work. And its strength will get down, it will easy to get plastic deformation then make the surface subsides. However, if the temperature of the preheating is too low, the temperature of the surface has a big change. With high heat stress, get the crackle is more easily. The temperature of preheating for H13 steel mold is at the range of 250-300℃.

That can reduce the temperature difference between the mold and the forgeable piece to avoid excessive thermal stress on the surface of the mold, and effectively avoid the plastic deformation of the mold surface.

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The Bright High Speed Steel M2 is known for its balanced combination of abrasion resistance, toughness and good red hardness. it is a tungsten-molybdenum high speed tool steel, m2 tool steel is used in a variety of applications and worldwide. M2 tool steel is the most popular high speed steel because of its superior qualities. As a result of its low carbon content, M2 tool steel high speed tool steel has an outstanding combination of toughness properties and abrasion resistance when correctly hardened and tempered.

M2 tool steel equivalent with JIS SKH51, SKH9, DIN WN-r 1.3343, GB W6Mo5Cr4V2 .

Today i have received a new inquiry from my client , he request for the Bright High Speed Steel M2 Round bar . The client was a wholesaler have business in Serbia, also their activities are in industrial spare parts like machine spare parts, Cutting and Grinding wheels, ball Bearing, Roller chains, Twist drill bits, hand and Machines TAPS AND DIE, Hoists and Cranes, screwdriver Bits, Crown wheel and pinion for passenger car and Gundrills/Masonry drill bits and etc… .

They would like purchase Bright High Speed Steel M2 with high quality round bars or raw materials that suitable for Twist Drill Bits DIN 338 HSS/HSS Co5%/HSS Co8% sizes of 1.0 mm to 20 mm .

And after communicate with customers , we found that he did not need Bright High Speed Steel M2 . Also the M42 have Cobalt 7.75-8.75 , M35 have Cobalt 4.6-5.0 did not meeting his requirement of Cobalt less than 5% . Which he needed was High Speed Steel 1.3243 . The standards should be W-Nr. German rules .

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42CrMo4 material is the Germany standard, another number is 1.7225. In American standard, it is AISI 4140 or SAE 4140.

We met some overseas customers who purchase the 42CrMo4 material very frequently from us afterwards. They asked us the question before, compared the steel mill, what is your company’s advantages?

We are the professional stockist including the tooling steel, high speed steel, alloy steel and carbon steel for more than 20 years.We have our own warehouse for stocking the different steel material, like the 42CrMo4 material.

As we have our machine equipments, such as CNC flame cutting , horizontal and vertical saw cutting machine, Grinding and Milling machine. Therefore, we could make the different machining as the customer’s special request. However, the factory mills are difficult on supporting it by tailor-made.

For making sure and testing the quality, we have Chemical Spectrometer, Ultrasonic Tester and hardness tester.
We could support the customer in lower MOQ, say 2-3Tons for each size.But from the mill, the MOQ is very huge. Usually in the mill, the MOQ for each size is ranged in 30 to 50Tons.

What’s more, we could make the more flexible payment terms as customers’ request. For example T/T, D/A,D/P, L/C, Western Union, MoneyGram. But for the Mills, they only accept the payment terms in 100% pay in advance.
At last, for the packing way, we could fulfill different customers’ request accordingly. But the mills will follow their own packing way by company’s policy.

Now for supporting and fulfilling the customers’ request, our company stocked many steel plates for the running 42CrMo4 material. For this 42CrMo4 material we would like to special highlight on this. It is produced by the only imported advanced steel making equipment. Moreover, the quality is approved by Uddeholm and certificated by the 3rd party SGS. Most of the customers often place the 42CrMo4 material repeat order to us because of the guaranteed quality, competitive price and fast delivery time.

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H13 application –Chapter 9

• The design of the H13 die steel

The design of mold depends on the shapes and specifications of products to make sure the size of the die for H13. H13 die steel was good for the strength of die in tooling steel.

Furthermore, too small a radius of a rounded corner, ill-suited groove position and etc will make the die gets big pressure during the heat treatment. H13  is easy to cause crackle. So H13 must make the taper angle, hole and etc at the right position in the mold.

• Production technique-H13

1. Forging ProcessThere are so many alloy elements in H13 steel. The resistance of deformation is big at the time of forging. And the thermal conductivity of the material is bad. So the eutectic temperature is low.  H13  is easy to burn. So the preheated temperature range must be at 800-900℃. Then heated to the initial forging temperature of 1065-1175℃. In order to crush large non-metallic inclusions and make the carbide get small, the forging ratio needs to be bigger than four. At the cooling process after forging, it is possible to get quenching crack. And the core is easy to get transverse cracks. So H13 steel must be slowly cooled after the forging.  The machining of cutting The roughness of the surface of H13  after the machining of cutting, H13has a large impact on the thermal fatigue property of steel mold. The roughness of the steel mold surface of H13 must be lower. The knife mark and cullet cut are not supposed at here. Those shortages will cause pressure over control to make the thermal fatigue crack. So, must pay attention to handle these things in the mold at the time of processing. 3. The machining of grinding At the process of grinding, the generation of heat by friction at the parts which is easy to cause the problems of crack, pyrosis and etc.

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Today is the first day to office in 2020 new year , and the first big good news was that Otai Special Steel have sales promotion for AISI 4140 preharded plate . We have more than 500 Tons stocklist in our warehouse with mixed size for thickness from 20MM to 180MM , we prepare this alloy steel AISI 4140 preharded plate to thanks our valued client for the support to our company in the past year of 2019 , and other special big thickness and different delivery conditions could be special ordered . If you have any interesting , please contact with me directly by e-mail : monica@otaisteel.com and whatsapp : +86 13711903397 , we will send you the quotation with best price as soon as possible .

In the past year of 2019 , we have sold more than 5000 Tons AISI 4140 preharded plate and round bar ,  4140PH is a chromium-manganese-molybdenum grade . This grade is delivered in a prehardened condition at a hardness level of 33/37HRC . The grade has a fully homogeneous martensitebainite microstructure .  4140PH grade has specific sulfur addition (0.060% typical) in order to increase strongly its machinability .

AISI 4140 preharded plate grade performs very well in drilling and in milling using high speed steel or carbide tools. The machinability of 4140PH is increased by a controlled sulfur addition which gives: • 500% increase in milling tool life (at constant cutting speed) • 300% increase in drilling speed • 30% increase in milling speed .

AISI 4140 preharded plate and steel bar, flat material can be used for as wide variety of applications where greater toughness and wear resistance is needed over lower carbon grades. Typical applications for 4140 tool steel uses include Components, Adapters, Arbors,strippers, holder blocks, mold bases, ejectors, back up and support tooling, fixtures, jigs, molds, cams, drill collars, Axle Shafts, Bolts, Crankshafts,stubs, couplings, reamer bodies, axles, shafting, piston rods, rams, hydraulic machinery shafts, gears, sprockets, gear racks, chain links, spindles, tool bodies, tool holders, tie rods, Connection Rods, Chuck Bodies, Collets, Conveyor Pins & Rolls, Ejector Pins, Forks, Gears, Guide Rods, Hydraulic Shafts & Parts,Lathe Spindles, Logging Parts, Milling Spindles, Motor Shafts, Nuts, Pinch Bars, Pinions, Pump Shafts,boring bars,tracks, slides, wear strips or parts, forming dies, brake dies, trim dies, bolsters, machinery parts and components, etc.

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Our plastic mould steel is highly corrosion-resistant and used to process plastic moulds, which can contain chemically aggressive or abrasive fillers.

Happy new year! Time flies, the 2020 year has already come, Otai wishes you a prosperous and happy 2020.

I’d like to share the plastic mold steel with you, plastic mould steel, does it plastic or real steel? it’s real steel.

All production mold tools ought to be made out of high-quality metals suitable BS, ASTM or DIN standards.

Several unique metals are occasionally utilized.

 the principal Plastic mould steel employed fall into three types:

 Alloy Steel

Alloy steels are generally used in cavities as well as for any plates which come into straight exposure to the mould materials. Alloy steels may be utilized in their softer condition or might be entirely hardened based on the utility.

Typically, all cavity components are generally totally hardened, because they should stand up to cyclical substantial loading, wear and thermal strains. Cavity holding plates and various other shuts off places are typically manufactured from the soft model. They just don’t want the greater strength and wear prevention that the hardened metal provides but they do present a better standard of shelter against damage than would mild metal.

 Mild Steel

This metal is normally utilized for all other tool plates. Mild steel mustn’t be used in cavity inserts or get in touch with the mould material. It ought to never be applied exactly where it should be subject to extreme sliding conditions, etc for the quality control reason. Occasionally manufacturers prefer to try a higher- carbon-content metal on long-running tasks to get greater ability to resist damage.

 Beryllium-Copper

This kind of material is an alloy of beryllium and copper. Beryllium is normally preferred because of its strength and copper for the thermal characteristics. It is going to conduct heat away speedily plus much more easily than steel.

Otai Special steel company is a stable and reliable supplier for fortune 500 companies at home and abroad, such as Thyssenkrupp, china north industries group corporation limited. waiting for your good news.

Mr Jack Tan

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Email: jack@otaisteel.com

We are the 4340 steel suppliers, we not only supply this alloy steel, but also the carbon steel, tool steel and high speed steel. We are happy and proud for we are expert in this steel material field for more than 20years.

Otai is as the 4340 steel suppliers, we always keep on being the one who can be reliable for all of you guys.
Today I would like to talk about “made in China”. Many many years ago, you may think that when mentioned “make in China”, Many people’s first impressions are poor quality and bad reputation.
But now not any more, in fact, China in last decades has developed super fast. Not only fast a little but fast in a big development. In many ways, such as, countries, development construction and technology.

Next I would like to summarize the important developments of China in 2019. As Chinese, we are very proud of seeing the prosperity of our motherland. We are proud because we and ours are made in China.
1) “Chang’e-4″ landed autonomously on the back of the moon, returning the world’s first close-up image of the moon back.
2) China Aerospace successfully completed its first maritime launch.
3) The 50th and 51st Beidou navigation satellite was successfully launched
4) The Great Wall V Yaoyao 3 launch vehicle was successfully launched
5) China’s 5G commercial use
6) The new super-long version of the ” Renaissance EMU” train doubled its capacity.
7)”Water Cube” changed to “Ice Cube” for the 2022 Beijing Winter Olympics
8) China’s “Bridge King” Yangsi Port Yangtze River Bridge was completed and opened to traffic.

In addition, China rectifies and reforms Chinese steel mills in 2019. And some small-scale steel mills and unqualified steel mills were closed. These are all improvements that the motherland has made for the quality and development of Chinese manufacturing.
The previous steel material market environment was quite chaotic. Some 4340 steel suppliers may attract customers with lower prices, and take the customers benefits no consideration. The 4340 steel suppliers find the steel mills with small-scale or unqualified to produce it.

Of course, this does not mean that such problems have been completely avoided after rectification. Everyone has different values, so each company has different culture and values. We cannot guarantee or require that someone need to be reliable, but our OTAI Special Steel insist on being ourselves. We are being the one who can be reliable by our dear customers. This is the most basic and best we could do for them.

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Email: jack@otaisteel.com

H13 application –Chapter 8

H13 steel is the most widely used of the hot work mold steel in the world. H13 has great heat intensity properties, hardness and wear resistance. The toughness and anti-fatigue performance of H13  are good.H13 is widely used to make all kinds of hammer dies, hot-extrusion dies and etc. H13  -Hot die steel needs to sustain huge impulse load, friction and high-temperature oxidation. But h13 something always happens during work time. Such as the crack, dent, abrasion, formation of cracking and etc. The chemical composition chart of H13 die steel as below.

Its characteristics of chemical composition of   H13

H13  carbon content can make sure the high hardness, toughness and other properties.

Adding the elements Cr, Mn, Si, Mn, H13  can make the hardenability get better to change the nature and shape of the oxide in the time of steel become solidification. H13 That move can avoid the formation of low melting point Fes on the grain boundary. Instead, existence as Mns with certain plasticity. Then it will clean out the bad influence of sulfur to make the hot workability of H13 mold steel. Adding the elements of Mo, V to make it harden secondary. And it can enhance temper resistance.

The factors of failure-H13 STEEL

H13  is a complicated question. But we can analysis it on four ways of material, design, manufacture and use.

• Chemical composition and the quality of material of H13

H13 steel belongs to the type of graphitic alloy steel. H13 have  so many nonmetallic inclusion in it. And H13 has the defects of the center be loosen and etc. H13  will make the strength, toughness and etc get down. And the quality of H13 steel has two levels for common and high-quality. High quality H13 steel is made from high technology and material. H13 has better toughness and thermal fatigue property. However, the common one needs the processing of forging. H13 will destroy the big non-metallic inclusion and make the carbide get small.

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

We are familiar about China market, have abundant knowledge at steel industry, and we have confidence about the material we supply, but we understand our customer do not trust us until they receive our material. As a steel supplier, for business cooperation, the most important and most difficult point is how to start the first order, especially when the buyer already have stable steel supplier. This article I would like share an Argentina customer’s story.

Argentina customer story, try to be their alternative steel supplier

This Argentina customer is important steel supplier in local market, they import steel in China, Turkey, Brazil and America. They also sell special steel 1045, 4140, 4340, D2, H13, P20, all mentioned are our main product. I try to contact this company since one year ago. I shared with them our company information, video, certification, inspection report, price promotion information, shipping information, and price trend analysis, try to show them OTAI Steel is professional steel supplier. The buyer read each of my email, but always keep silence. Until last month, I shared with them 4340 SGS inspection report and our sales data in Latin American market, the buyer Mr Alex reply me, they already have stable steel supplier, worked with them smoothly, and will not change supplier this moment.

I admit I am a sales person not easy to give up. I replied him an email the same day.

Dear Alex:

We just hope can be your secondary source.

I understand you do not want spend additional time and energy to explore new supplier. I worked as international purchaser before. Our supply chain was fragile when we are limited to a single supplier, I remember we have face problems as follow:

1) We could not ship the order to customer because quality issue of one key part (sole supplier) quality issue.

2) Customer increase order a lot, lead to bad result that we cannot fulfil the order in time.

3) Suppler increase price in a sudden and not reasonable, no enough time to explore new supplier, then have to cut our profit.

4) Our company missed high-quality customers due to the supplier’s non-cooperation.

All above lead to us must explore 1-2 alternative suppliers for any material since then.

OTAI hope can be your alternative special steel supplier. You can send us RFQ, then we will send you quotation, then you can compare our price with currently steel supplier. We also can send you samples for inspection.

If our price accepted, our quality approved, I believe, your currently steel supplier also will provide you better price, more stable quality, better communication as well.

That night, I received RFQ from this customer, about plastic mold steel P20 and 1.2738. We discuss details, and Mr Alex consider a trail order to see our material quality. That’s a good start. We will be qualified alternative special steel supplier.

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The fluctuation of steel prices being  narrowed throughout 2019 , the pace of changes in prices quickly , and both the price and the industry’s profit center was fell in 2019.

Chinese Lunnar Year coming soon ( 26-Jan,2020 ), there is about 10-20 days holiday for Chinese Manufacture Industry. Here we talk about the Alloy steel  price infulecing factors 2 weeks  before and after Spring Festival .

The Factor of  Alloy steel USD unit price goes up :

• The average freight cost higher .

It is shipping season before Chinese Spring festival ,there is many vessel shchedule line will stop shipment or reduce their shipment line during Chinese Festival holiday .

As you know ,the price will go up in great shipment demand . According the newest offer from our shipment agent ,all the shipment cost by sea was go up 30% at least . Some shipment line ‘s freight twice as much as usual . (such as the Freight from Shanghai to Dubai ： 40GP ：800 USD on Oct.， now it is 1700 USD )

If the the Alloy steel offer base on CIF trade terms ,the offer will be higher even EXW price keep same as before .

• Machined process fee /Heat treatment cost /Domestic cost higher than usual

The new year coming soon ,and all the machined factory or heat treatment shop being crazy busy . And it is easy suffer Labor shortage before the Spring holiday . There is too many drivers for heavy trucks  also will have a holiday and back to hometown in advance ,it will lead to difficult to found a driver to help us shipment the Alloy steel from warehouse to Loading port .

Many production workers will leave their job ,and  look for a new job after Spring Holiday .It will lead to the labor cost higher than before ,then leadto the processing fee higher a little than usual .

Those reason have some influence of alloy steel order which need to processing again , such as do the Quenching and Tempering process ,or milling /Turning  process .

• The USD & RMB currency rate go down compared with Nov.2019 .

Ms Elwa Lee

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