AISI M35 Steel Round Bar Sheet Plate, JIS SKH55, DIN 1.3243

M35 steel is high speed tool steel . It also is called SKH55 steel and 1.3243 steel. After the heat treatment, its hardness, red hardness and wear resistance can be improved.M35 high speed steel is a good material for making tools which can handle high impact and abrasion. And it always is used to make advanced die, screw dies, reamer, milling cutter, iron head, punch, complex shape tools with high toughness. It is easy to do the hot and cold process. After the quenching and tempering, the hardness will be the same as M42 steel . And the hardness of them is 66±1HRC and 67±1 HRC. M35 steel round bar plate sheet properties and chemical composition as below.

AISI M35 Steel Round Bar Sheet Plate Supply Range
Round BarDia:1.3-300mm; Length: Can be customized;
Other specifications can be customized.
Black Surface/Bright Surface /Grinded/Peeled/Turned
As per given requirements.
Sheet/Plate/SlabThickness: 1.3-200mm; Width: 200-810mm;
Length: Can be customized;
Other specifications can be customized.
Black Surface/Bright Surface /Grinded/Peeled/Turned
As per given requirements.

M35 Steel Grade Equivalent Chart

StandardASTM A600EN ISO 4957-1999JIS G4403-2006ISO 4957-1999
GradesM35HS 6-5-2-5/1.3243SKH55HS 6-5-2-5
Delivery condition: In annealing (≤269HB), or after heat treatment (64-66HRC).  Quality control: 100% UT (Ultrasonic Testing), UT Standard is SEP 1921-84 C/c.

ASTM M35 Tool Steel Chemical Composition

STAND C(%) Mn(%) P(%) S(%) Si(%) Cr(%) V(%) W(%) Mo(%) Co(%)
ASTM A600 0.82-0.95 0.15-0.40 0.03 0.03 0.20-0.45 3.80-4.50 1.75-2.15 5.50-6.50 4.75-5.25 4.60-5.00
EN ISO 4957-1999 0.87-0.95 ≤0.40 0.03 0.03 ≤0.45 3.80-4.50 1.70-2.10 5.90-6.70 4.70-5.20 4.50-5.00
JIS G4403 : 2006 0.87-0.95 ≤0.40 ≤0.030 ≤0.030 ≤0.45 3.80-4.50 1.70-2.10 5.90-6.70 4.70-5.20 4.50-5.00
ISO 4957-1999 0.87-0.95 ≤0.40 ≤0.030 ≤0.030 ≤0.45 3.80-4.50 1.70-2.10 5.90-6.70 4.70-5.20 4.50-5.00

SAE M35 HSS Steel Physical Properties

Physical Properties Metric Imperial
Density 8.14 g/cm³ 0.294 lb/in³

M35 High Speed Steel Mechanical Properties

Mechanical properties Metric Imperial
Hardness, Rockwell C (oil quenched from 1232°C, 5 mins) 64.8 64.8
Hardness, Rockwell C (oil quenched from 1177°C, 5 mins) 65.2 65.2
Hardness, Rockwell C (oil quenched from 1204°C, 5 mins) 65.2 65.2
Modulus of elasticity 207 GPa 30000ksi
Machinability (1% carbon steel) 45.0-50.0% 45.0-50.0%

M35 Steel Round Bar Application


1.It can be made all kinds of high hardness cutting tools. Such as saw blades, drills, taps, broaches, hobs and various milling cutters.
2.Also, it is good material for cold forging dies, drawing dies, cutting tools and etc.
3.It is widely used in the cold stamping products industry such as watch case factory and screw factory.

It is suitable for the manufacture of wear-resistant and impact-resistant high-hardness tools for powerful cutting, advanced punching dies, screw dies, tools that require toughness and complex shapes, reamers, milling cutters, iron heads, punches, etc. The main uses are saw blades, drills, taps, hobs, broaches, end mills and various milling cutters, etc. It is also an excellent material for cold forging dies, wire drawing dies, knives, etc. It is widely used in cold stamping products industries such as watch case factories and screw factories.

1.3243 Steel Characteristics

M35 and M42 are the most popular high speed steel grades in the international. The alloy element content of M35 steel is higher, and also has the cobalt element. So its red hardness is higher. It has great hardness at high temperature. The hot hardness, machinability and wearing resistance are good.

M35 Steel Round Bar Sheet Plate Heat Treatment

1.3243 Steel Forging Technology

The alloy element content of M35 steel is more than 22%. It is higher than M2 steel about 30%. It’s forging is difficult. You need to pay attention to it as the same as M42 steel forging. First of all, preheat it fully, the heat temperature is 1120℃ – 1150℃. And the temperature of the beginning is 1000℃ – 1050℃, the ending of it is must higher than 899℃. After forging, it should cold slowly and annealing on time to prevent cracking.

M35 Steel Annealing Process

If you case it up for the annealing after the forging, you will get a better result. If you can not do that, just make it cold to the indoor temperature then make it in. About the annealing process, just put it in the stove with the temperature which is lower than 500℃. Then heat to 840-860℃, keep the temperature for four to five hours. Furnace cooling to 500℃ below than out of it. Cooling slowly in the annealing furnace. After the annealing, its hardness is lower than 255HB.
In order to prevent oxidative decarburization happen, the annealing should be careful. And there is an easy way can do that. Just put some wood dust to the annealing furnace.

1.3243 Steel Forging Technology

Heat Temperature in Quenching( ℃ )Quenching Grain Fineness Number( Level )Hardness for after Quenching( HRC )Hardness for after Tempering( HRC )

Notice for Quenching and Tempering

  1. Preheat two times: 600℃, 860℃. And the time of preheating is twice the time of heating.
  2. The request of quenching is 10-12s/mm.
  3. Needs the step hardening: 600℃→260-280℃→air cooling.
  4. The temperature of secondary hardening is 535-540℃ around. The hardness is bigger than 68HRC for after tempering. But the factories do not want the hardness of cutting tool is more than 68HRC due to the request for production. So it always is been tempering.

As we can see from the table, the best temperature for quenching is in the range of 1215-1225℃. In this condition, it is suitable for annual cutting tools. Its hardness is about 67-67.5HRC. It satisfies the needs of high speed steel high speed steel for high strength, high hardness and high wear resistance.

M35 steel that been quenching at the temperature below 1190℃ is good material for cold work die and low-speed cutting tools. And if it been quenching at the temperature higher than 1230℃ which will have a great red hardness. It will be a good choice for turning tools and etc. Quenching it in that way will cause overheating. But it is not a trouble, the key is to control it in the right way. Some cutting tools are overheating to be more useful.


In China, we have been focusing on the steel industry for decades, as a professional supplier, a powerful steel factory, advanced technology, high-quality steel, we have our own cutting and processing facilities. Specific specifications can be customized and customized according to your needs. Provide reliable M35 high speed steel products as well as other high speed steels, please contact us for any needs of high speed steel M35 steel.

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