24 July 2021 Hardware Tool Steel Bar
CrWMn Hardware Tool Steel Bar
CrWMn is the most commonly used high carbon alloy tool steel for making molds. CrWMn steel has high hardenability. Since tungsten forms carbides, this steel has more excess carbides and higher hardness and wear resistance than chromium steel and 9SiCr steel after quenching and low-temperature tempering.
In addition, tungsten also helps to preserve fine grains, so that the steel gets better toughness. Therefore, the cutting tool made of CrWMn steel has less chipping and can maintain the shape and size of the cutting edge.
However, steel is more sensitive to the formation of carbide networks. The existence of such a network causes the blade edge to be flaking off, thus shortening the service life of the tool.
Therefore, steels with carbide meshes must be based on their severity. Forging and normalizing. This type of steel is used to make tools that do not heat up sharply at the time of work and require gauges and cutting tools that do not deform when quenched, such as making knives, filament cones, long reamers, special milling cutters, dies, and other types of special tools. Tools, and cutters for cutting soft non-metallic materials.
Chemical Composition:
| C(％) | Si(％) | Mn(％) | P(％) | S(％) | Cr(％) | Ni(％) | W(%) | Cu(%) |
|---|---|---|---|---|---|---|---|---|
| 0.90～1.05 | ≤0.40 | 0.80～1.10 | ≤0.030 | ≤0.030 | 0.90～1.20 | ≤0.20 | 1.20～1.60 | ≤0.30 |
Mechanical Properties:
| Yield Rp0.2 (MPa) | Tensile Rm (MPa) | Impact KV/Ku (J) | Elongation A (%) | Reduction in cross section on fracture Z (%) | As-Heat-Treated Condition | Brinell hardness (HBW) |
|---|---|---|---|---|---|---|
| 834 (≥) | 364 (≥) | 32 | 33 | 23 | Solution and Aging, Annealing, Ausaging, Q+T,etc | 414 |
Physical Properties:
| Temperature (°C) | Modulus of elasticity (GPa) | Mean coefficient of thermal expansion 10-6/(°C) between 20(°C) and | Thermal conductivity (W/m·°C) | Specific thermal capacity (J/kg·°C) | Specific electrical resistivity (Ω mm²/m) | Density (kg/dm³) | Poisson’s coefficient, ν |
|---|---|---|---|---|---|---|---|
| 22 | - | - | 0.32 | - | |||
| 239 | 741 | - | 11.3 | 221 | - | ||
| 684 | - | 31 | 31.2 | 421 | 132 |