SDP/SI - Section 17 - Strength and Durability of Hardened Gears

T-157 Table 17-6 Induction Hardened Gears NOTES: 1. If a gear is not quenched completely, or not evenly, or has quenching cracks, the s_F lim will drop dramatically. 2. If the hardness after quenching is relatively low, the value of s_F lim should be that given in Table 17-5. Surface Hardness HV HB HV 167 189 231 252 210 221 231 242 252 263 242 252 263 273 284 295 305 316 327 337 160 180 220 240 200 210 220 230 240 250 230 240 250 260 270 280 290 300 310 320 21 21 21.5 22 23 23.5 24 24.5 25 25 27 28 29 30 31 32 33 34 35 36.5 More than 550 " " " More than 550 " " " " " More than 550 " " " " " " " " " Heat Treatment Before Induction Hardening Core Hardness Arrows indicate the ranges Material Structural Carbon Steel Hardened Throughout Structural Alloy Steel Hardened Throughout Hardened Except Root Area sF lim kgf/mm² G S48C H G S48C H G S43C H G S43C H G SMn443 H G SCM440 H G SNC836 | SCM435 H G SNCM439 H Normalized Quenched and Tempered Quenched and Tempered 75% of the above