,

W1 Tool steel


Water-hardening tool steels are also known as group W steels. This group consists of three types, namely, W1, W2, and W3. The main alloying element found in group W steels is carbon. To increase the wear resistance and hardenability of the W steels, a small amount of chromium can be added. By adding vanadium, the grain size is maintained, which enhances the toughness of the steels. The group W steels have low resistance to softening at high temperatures and are inexpensive.

The W1 steel is one of the most commonly available water hardening tool steel grades and can be easily hardened by heating and quenching in water. However, this alloy does undergo some amount of distortion during quenching. The following datasheet will provide details of W1 water-hardening tool steels.

Chemical Composition

The following table shows the chemical composition of W1 tools steels.

Element Content (%)
C 0.70-1.50
Mn 0.10-0.40
Si 0.10-0.40
Cr 0.15
Ni 0.2
Mo 0.1
W 0.15
V 0.1
Cu 0.2
P 0.025
S 0.025

Physical Properties

The physical properties of W1tool steels are outlined in the following table.

Properties Metric Imperial
Density 7.83 g/cm3 0.283 lb/in3
Melting point 1435°C 2615°F

Mechanical Properties

The mechanical properties of W1 steels are tabulated below.

Properties Metric Imperial
Tensile strength, ultimate 1680 MPa 244000 psi
Tensile strength, yield 1500 MPa 218000 psi
Poisson’s ratio (25°C) 0.27-0.30 0.27-0.30
Elongation at break 3.50% 3.50%
Bulk modulus 140 GPa 20300 ksi
Shear modulus 80.0 GPa 11600 ksi
Elastic modulus 190-210 GPa 27557-30458 ksi
Charpy impact, unnotched 86.0 J 63.4 ft-lb
Hardness, Brinell (converted from Rockwell C Hardness) 498 498
Hardness, Knoop (converted from Rockwell C Hardness) 558 558
Hardness, Rockwell C 50.0-51.0 50.0-51.0
Hardness, Vickers (converted from Rockwell C Hardness) 531 531
Machinability (based on AISI 1212 steel as 100% machinability) 40 40

Thermal Properties

The table below shows the thermal properties of W1 tool steels.

Properties Conditions
T (ºC) Treatment
Thermal expansion 10.4 x 10-6/ºC 20-100
Thermal conductivity 48.3 x W/mK 100

Other Designations

Other designations that are equivalent to AISI W1 tool steels include:

  • ASTM A686
  • SAE J437 (W108), (W109), (WhO), (W112)
  • SAE J438 (W108), (W109), (W110), (W112)
  • UNS T72301

Fabrication and Heat Treatment

Machinability

The machinability of W1 steels is very good as they are plain carbon steels with 100% rating based on which other tool steels are compared.

Forming

W1 steels can be easily formed using conventional methods.

Welding

W1 steels are weldable using all the standard methods.

Heat Treatment

The treatment depends upon the intricacy of the part or section size. W1 steels with large sections or intricate shapes have to be slowly preheated to 593°C (1100°F) and then the temperature should be slowly increased to 816°C (1500°F). The steels should be maintained at the same temperature for 10 to 30 minutes and finally water or brine quenched.

Forging

Forging of the W1 steels can be performed at 1038°C (1900°F) down to 816°C (1550°F) but not below 843°C (1500°F).

Hot Working

W1 steels can be hot-worked.

Cold Working

W1 steels in the annealed condition have very good ductility and can be easily cold worked using conventional methods.

Annealing

Annealing has to be performed at 760°C (1400°F) followed by slow furnace cooling at 4°C (40°F) per hour or less.

Tempering

Tempering of the W1 steels is performed at 177-343°C (350-650°F) to realize Rockwell C hardness of 64 to 50.

Applications

The W1 steels are mainly used for cold heading, hand-operated metal cutting tools, reamers and embossing taps. It is also used for cutlery.

SHOPPING CART

close