Hot Work Tool Steel
Precision Marshall’s FIRECHROME is an excellent hotwork tool steel, featuring a combination of shock resistance, red hardness and abrasion resistance. It is capable of withstanding rapid cooling and resists premature heat checking. Meets ASTM A-681 and W 2344.
Typical Analysis
| Carbon | .40 | Chromium | 5.00 |
| Manganese | .40 | Vanadium | 1.00 |
| Phosphorus | .03 max | Molybdenum | 1.20 |
| Sulfur | .03 max | Silicon | 1.00 |
Applications
Typical applications of FIRECHROME includes cores, diecasting dies, die holder blocks, hot forging dies, hot extrusion dies, hot press dies and hot work punches.
Annealing
Vaccum furnaces or atmosphere-controlled furnaces should be used when available. If unavailable, tools should be wrapped in stainless foil or packed in a neutral protective compound. Heat uniformly to 1550/1650°F and hold at the annealing temperature for one hour per inch of cross section. Cool in the furnace at a rate not exceeding 50°F per hour down to a temperature of 1000°F, after which a faster rate may be allowed.
Heat Treating
Vacuum furnaces or protective atmosphere furnaces are recommended to prevent decarburization. Preheat thoroughly to 1450/1500°F and heat to 1800/1875°F, hold 30 minutes at temperature. Pressure quench in vacuum or air cool to 150°F, then temper immediately. If complicated designs or large sections are to be heat treated, an interrupted oil quench to 1000°F may be used. After preheating to 1400°F for one half to one hour, heat to 1825/1875°F and soak one half hour when material is up to temperature. Air cool to hand warm (approximately 150°F) and temper immediately.
Tempering
Double temper one hour per inch of section thickness, two hours minimum per temper. Representative hardness levels after tempering are tabulated below.
Air quenched from 1800°F • Tempered 4 to 6 Hours
(Section Size — 4” x 4”)
| Tempering Temperature (°F) | Rockwell Hardness (RC) |
| As quenched | 48/50 |
| 1000 | 50/52 |
| 1050 | 47/49 |
| 1100 | 46/48 |
| 1150 | 43/45 |
| 1200 | 32/34 |
EDM
Electro-discharge machining is used in the production of various tooling. This process produces recast, rehardened and retempered layers on the EDM surface.
It is recommended that FIRECHROME be stress relieved at 50°F below the final tool tempering temperature, after the EDM process, to temper the rehardened layer produced by EDM.
Condition
FIRECHROME H-13 is provided completely decarb free and stress relieved.
Finish
Ground oversize to typical rms 50/75, maximum 125.
Sizes
Available in standard thickness increments 3/8” thru 6”.