Characteristic
Chromium is the primary alloying element of martensitic steels such
as 1.4057 stainless steel, imparting moderate corrosion resistance
to a material with inherently high hardness and strength. In the
unquenched and un-tempered condition, martensitic grades are
brittle and unsuitable for engineering applications. Typically,
nickel concentrations of 2 – 2.5% are added as a stabilizing
element to ensure a martensitic steel retains its toughness
properties through heat treatment, enabling the fabrication of
numerous component types. Medical tools and mechanical components
are among the most common devices constructed from martensitic
steels.
Use
Laboratory equipment
Marine systems
Beater bars
Pump and propeller shafts
Nuts and bolts
Chemical Composition
| Grade | C | Mn | Si | P | S | Cr | Ni |
| 1.4057 | min. | – | – | – | – | – | 15 | 1.25 |
| max. | 0.2 | 1 | 1 | 0.04 | 0.03 | 17 | 2.5 |
Physical Properties
| Physical Properties |
| Density, g/cm3 (lb/in3) | 7,7 (0.278) |
| Magnetic | Yes |
| Specific heat capacity, J/(Kg·K) | 460 at 20 °C (68 °F) |
| Electrical resistivity, μΩ·m | 0.70 at 20 °C (68 °F) |
| Modulus of elasticity (Elastic Modulus) , Gpa (10³ ksi) | 215 (31.2) at 20 °C (68 °F) |
| 212 (30.7) at 100 °C (212 °F) |
| 205 (29.7) at 200 °C (392 °F) |
| 200 (29) at 300 °C (572 °F) |
|
| Thermal conductivity, (W/m·K) | 25 at 20 °C (68 °F) |
| Mean coefficient of thermal expansion, (10-6/K) | 10,0 at 20-100 °C (68-212 °F) |
| 10,5 at 20-200 °C (68-392 °F) |
| 10,5 at 20-300 °C (68-572 °F) |
| 10,5 at 20-400 °C (68-752 °F) |
The difference between martensitic stainless steel and austenitic
stainless steel:
The main alloying element in martensitic stainless steel is
chromium.
Usually used in weakly corrosive media, such as sea water, fresh
water and steam, the use of temperature less than or equal to 580 °
C, usually as a large force parts and tools of the production of
materials, due to the poor welding performance of this steel, it is
generally not used as welding parts.
The main alloying elements in austenitic stainless steel are
chromium and nickel. This kind of steel has high toughness, low
brittle transition temperature, good corrosion resistance and high
temperature strength, good oxidation resistance and good pressure
processing and welding properties.
Martensitic stainless steel: Through heat treatment can adjust its
mechanical properties of stainless steel, in popular terms, is a
class of hardened stainless steel. The typical grade is Cr13 type,
such as 2Cr13,3Cr13,4Cr13, etc. High hardness after quenching,
different tempering temperature has different strength and
toughness combination, mainly used in steam turbine blades,
tableware, surgical instruments. According to the difference in
chemical composition, martensitic stainless steel can be divided
into martensitic chromium steel and martensitic chromium-nickel
steel two categories.
Austenitic stainless steel: It refers to stainless steel with
austenitic structure at room temperature. When Cr is about 18%, Ni
8%-10% and C is about 0.1%, the steel has a stable austenitic
structure. Austenitic chromium-nickel stainless steel includes the
famous 18Cr-8Ni steel and the high Cr-Ni series steel developed on
this basis by increasing the content of Cr and Ni and adding Mo,
Cu, Si, Nb, Ti and other elements. Austenitic stainless steel is
non-magnetic and has high toughness and plasticity, but the
strength is low, it is impossible to strengthen it through phase
change, and it can only be strengthened by cold working, such as
adding S, Ca, Se, Te and other elements, it has good machinability.
Product Testing
Coating Thk Test
Geometry inspection
Ultrasonic Inspection
Nondestructive Testing
Hydrostatic Testing
Package Process
1.with plastic cap to protect both ends
2.weaving bag wrapped outside the pipe
3.then pack into wooden case.
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