Specifica tions Furnished in 18" and 36" lengths, ground straight and parallel. Hardening 497 and 499 Air Hardening Ground Flat Stock have a wide hardening range of 1700ºF to 1775ºF, with 1750ºF recommended for most work. For heavier sections use the high side of the range. Heat uniformly throughout but do not soak longer than necessary. Cool in still air. No pre-heat is required if pack or atmosphere controlled furnace methods are used, but with the open furnace method a pre-heat of 1450ºF is recommended. Tempering A tempering time of two hours at temperature is recommended. Use chart for selecting the desired Rockwell C hardness and corresponding tempering temperature. For maximum toughness, double temper for two hours at each temperature recommended. The following may also be used as a guide, depending on the type of work. Light Blanking Punches and Dies • 400º-425º F Hea vy Blanking Punches and Dies • 700º F Annealing 1525º-1575ºF.Furnacecoolatnomorethan50ºperhourto800ºformaximumsoftness. 497 Air Hardening Precision Ground Fla t Stock STANDARD 499 Air Hardening Precision Ground Fla t Stock OVERSIZE Dimensionally st able • The 5% chromium content makes this steel especially desirable for punches and dies to be used in long production runs since it gives the tools far longer life. Up to 50% more pieces per sharpening can be produced than with oil hardening steel. • High wear resistance is also ideal for punches and dies to stamp silicon, stainless steels, monel metal and other types of abrasive material • Maintains close dimensional accuracy throughout the heat treating process. The wide 75º hardening range make this virtually foolproof. • Full-lengthidentificationeliminatesconfusionwithothersteels • Starrett uses its own ground flat stock for many of its precision tool parts 60 50 40 30 200 400 600 800 1000 1200 499, 1-1/4" and over is Blanchard ground with saw cut edges Nominal Analysis (AISI A2) Carbon .............................................................. 1.00 Chromium ......................................................... 5.25 Manganese ........................................................ .60 Molybdenum ...................................................... 1.00 Vanadium .......................................................... .25 Precision Ground Fla t Stock Size Temperature Cool Rockwell C All Sizes 1700º-1775º F Still Air 63.5-65 1775°F HARDENING TEMPERATURE 1700°F HARDENING TEMPERATURE AS HARDENED ROCKWELL C 63.5-65.0 TEMPERING TEMPERATURE °F ROCKWELL C HARDNESS TWO HOURS TEMPERING RECOMMENDED 556 F la t S tock and D rill R od