GENERAL DESCRIPTION
The 223X overlay alloy for steel plate has been developed for applications requiring resistance to extreme abrasion, at temperatures requiring resistance to extreme abrasion, at temperatures up to 755°C (1,400°F), combined with moderate to low impact.
TYPICAL PROPERTIES OF UNDILUTED T223X ALLOY
The properties given directly below refer only to the T223X alloy, undiluted by base material (substrate). The properties differ from the properties of actual overlay deposits on a particular substrate, examples of which are given in the next section.
| Type of alloy | Iron based |
| Group of alloys | High chromium iron |
| Nominal composition (undiluted) | 5.6% C, 0.7% Mn, 27% Cr, 5% Mo, 1.25% W, 1.0% V, 5.5% Nb |
| Microstructure | Hyper-Eutectic with M7C3 primary chromium carbides in an |
| austenitic eutectic matrix, complex Mo-W-V carbides and added Nb-carbides | |
| Typical hardness range | 62-64 Rc |
| Cracking | Yes |
| Abrasion resistance | Excellent, very high |
| Impact resistance | Moderate to low |
| Typical service temperature | Up to 755°C (1,400°F) |
| Machining | Only grinding |
| Flame cutting | No |
TYPICAL PROPERTIES OF T223X OVERLAID PLATES
Standard Base plate grades
| in the USA: | ASTM A-36 |
| in the UK | BSEN 10025:1993 Fe 430A (BS 4260-43A) |
Typical chemical compositions and hardnesses of single and double layer overlays:
| Element | C | Mn | Cr | Mo | W | V | Nb | Fe | Hrc | |
| Single layer | Wt% | 4.6 | 0.8 | 21 | 4 | 1 | 0.7 | 4.5 | Remainder | 56-58 |
| Second layer | Wt% | 4.9 | 1 | 24 | 4.5 | 1.1 | 0.8 | 5 | Remainder | 58-62 |
AREAS OF INDUSTRIAL USE
T223X overlaid plates are used in many segments of industry: Steelworks, Dredging, Mining, Refineries, Cement, Glass, Timber, Power Generation Plants, Earthmoving, Sugar Mills, etc.
TYPICAL FIELDS OF APPLICATION
The 223X alloy can be used throughout the full range of temperatures from ambient up to 650°C (1200°F).
Typical applications in the higher temperature range are:
Burden ares of blast furnace bells and hoppers
Paul Wurth blast furnace charging devices
Blast furnace charge deflecting bars
Hot sinter screens
Hot gas/dust exhaust fan blades coke plant equipment
Pelletising plant equipment
Bottom ash screws, etc.
MACHINING, CUTTING, WELDING AND REPAIR OF T223X PLATES
Edge and surfaces may be ground with an abrasive disk.
The high chromium content of the alloy is incompatible with the use of oxy-fuel flame cutting processes.
Plasma-arc is the generally preferred method of cutting. The quality of plasma cutting excellent, in terms of both precision and cleanliness.