1.8519 - AT A GLANCE
What kind of steel is the 1.8519?
The steel grade 1.8519 also known under its chemical discription 31CrMoV9 is a nitridable steel and will be delivered in the tempered condition. It is used for applications needing high wear resistance. The nitriding process makes it possible to give it a higher surface hardness that can reach approx. 800 HV (approx. 64 HRC). This steel grade can be found in the automotive industry, in machine and plant engineering as well as the motor and piston construction.
Properties
The 1.8519 is a CrMoV9 alloyed steel that finds it uses in the automotive industry as well as mechanical engineering.
It is deliverd tempered and is often used for components subjected to wear. For a better wear and corrosion resistance this steel grade can be nitridied. Nitriding can achieve a nitrading hardness of approx. 800 HV (64 HRC).
- Nitriding steel
- Enginnering steel
- Tempered
- High wear resistance
- High pressure resistance
- High toughness
- Good machinability
- Nitridable
- Difficult to weld
Applications
The tempered 1.8519 can be found in a variety of industries and is used for many applications. Due to its high wear resistance it is often used for components exposed to high stresses.
- Automotive industry
- Drive technology
- Mechanical engineering
- Valve construction
- Plant construction
- Engine construction
- Piston construction
- Connecting rods
- Gears
- Valve spindels
- Measuring tools
1.8519Standard values
Chemical composition:
| C | Si | Mn | P | S | Cr | Mo | V |
|---|---|---|---|---|---|---|---|
| 0.27 - 0.34 | 0.0 - 0.4 | 0.4 - 0.7 | 0.0 - 0.025 | 0.0 - 0.035 | 2.3 - 2.7 | 0.15 - 0.25 | 0.10 - 0.25 |
Chemical designation:
31CrMoV9
Working hardness: max. 64 HRC (nitiriding hardness)
Delivery condition:
max. 352 HB
1.8519 Physical Properties
What group of steel does the 1.8519 belong to?
- Nitriding steel
- High grade structural steel
Is the 1.8519 a stainless steel?
No, the 1.8519 is not a stainless steel in the classical sense.
Is the 1.8519 corrosion resistant?
No, the 1.8519 is not corrosion resistant. To be corrosion resistant a material has to have a mass fraction of at least 10,5 % chromium. The 1.8519 has a mass fraction of 2,3 – 2,7 % of chromium.
Is the 1.8519 magnetisable?
The 1.8519 is a ferromagnetic steel and can be magnetised. For milling or grinding, this steel grade can therefore be placed on a magnetic clamping plate.
1.8519 Wear resistance
For its wear resistance the 1.8519 receives a 6 on a scale where 1 is low and 6 is high.
1.8519 Technical properties
1.8519 Working hardness
The 1.8519 can reach a working hardness of 64 HRC.
1.8519 Density
At room temperature the nirtriding steel 1.8519 has a density of 7,73 g/cm3.
1.8519 Tensile strength
1.8519 has a tensile strength of approx. 1100 N/mm². To obtain these findings, a tensile test is carried out to show how much force is required to stretch or elongate a sample before it breaks.
1.8519 Yield strength
The yield strength indicates how much stress can be applied before a material undergoes plastic deformation. Beyond this point, the material does not return to its original shape when the stress is removed, but remains deformed or even breaks. The yield strength for 1.8519 in its tempered condition is 700 N/mm2.
1.8519 Machinability
On a scale where 1 is low and 6 is high the 1.8519 receives a 3 for its machinability.
1.8519 Heat conductivity
At room temperature, the thermal conductivity of high grade structural steel 1.8519 is 25.7 W/(m*K).
1.8519 Thermal expansion coefficient
The following table shows the expansion or contraction at different temperatures, which can be very important for work at high temperatures or with significant temperature fluctuations.
Medium thermal expansion coefficient
Value tempered
10-6m/(m*K)
At a temeprature of
12.1
20 – 100 °C
12.7
20 – 200 °C
13.2
20 – 300 °C
13.7
20 – 400 °C
1.8519 Specific heat capacity
The specific heat capacity of this nitriding steel at room temperature is 0.441 J/kg*K. This value indicates how much heat is required to heat a certain amount of material by 1 Kelvin.
1.8519 Specific electrical resistance
The specific electrical resistance for this steel grade can be found in the following table. Electrical conductivity is the reciprocal of the specific electrical resistance.
Table of the specific electrical resistivity
Value (Ohm*mm²)/m
At a temperature of
0.19
20 °C
HIGHEST PRECISION!
1.8519 Procedure
1.8519 Heat treatment
The heat treatment process determines the properties of materials. It should therefore always be carried out with care. Properties such as strength, toughness, surface hardness and temperature resistance are determined, which in turn can extend/improve the service life of parts, tools and components.
Heat treatment includes solution annealing, soft annealing, normalising, stress relief annealing, but also tempering, hardening and quenching or tempering.
1.8519 Annealing
To anneal, the 1.8519 is heated evenly to a temperature of 680–720 °C and then cooled in the furnace.
1.8519 Normalising
For normalising, the 1.8519 is heated evenly to a temperature of 870–900 °C and then cooled in air.
1.8519 Stress relieving
To remove internal stresses, the 1.8519 is heated evenly to a temperature of 550–580 °C and held there. Finally, the material is slowly cooled in the furnace to prevent the rebuilding of internal stresses.
1.8519 Tempering
To temper the 1.8519 is heated evenly to a temperature of 580 – 660 °C and held at this temperature for approx. one hour. It can then be allowed to cool slowly in the air.
1.8519 Hardening
The 1.8519 material is heated evenly to a temperature of 840–880 °C and then quenched.
1.8519 Quenching
After hardening, material 1.8519 can be slowly quenched in one of the following media:
- Oil
- Water
1.8519 Continous TTT-diagram
This diagram shows micro-changes over time at different temperatures. These are important in heat treatment, as they provide information about the optimal conditions for processes such as hardening, annealing and normalising.
1.8519 Isothermal TTT-diagram
This diagram shows the structural changes at the micro level over time at a constant temperature. It shows at what temperature and after what time different phases, e.g. perlite, martensite or bainite, begin to form.
1.8519 Surface treatment
1.8519 Nitriding
The introduction of nitrogen into the material surface creates a hard and wear-resistant layer that increases wear resistance and service life. The thickness of the nitriding layer should be carefully considered to suit the respective application.
1.8519 Carbonitriding
Through this process, nitrogen and carbon is diffused into the surface of the metal, giving it greater hardness and wear resistance.
1.8519 Induction hardening
Induction hardening, also known as surface hardening, gives workpieces increased surface hardness and wear resistance with a tough core. With induction hardening, however, only specific areas can be heated and hardened. To complete the induction hardening process, the workpieces are quenched.
1.8519 Phosphating
In this process, a phosphate solution is sprayed onto the component or it is immersed in a phosphate solution. The resulting phosphate layer on the component improves corrosion resistance and can also form the basis for further coating, such as painting.
1.8519 Processing
1.8519 Forging
The material 1.8519 is heated evenly to a temperature range of 850–1050 °C for hot forming and then formed. The material should then be allowed to cool slowly in still air. Finally, heat treatment and tempering can be carried out.
