SAE/AISI 10B38（IFI-10B38）

ASTM F2282—18, original Table4/7 and Table6/9; heat/heat analysis, mass fraction wt%, not measured heat-analysis results. The IFI designation and /A and /B groups are retained separately as printed; equivalence to a same-number SAE grade is not assumed. /B is not a boron marker within a numerical designation. Residual maxima for Table9 apply only to elements without specified alloy ranges and do not override the alloy Ni/Cr/Mo range for Table7. Table6 Si follows the actual deoxidation method. Fine-grain requirements, grain-size reporting and agreements on 7.2 Al content/S2 require separate verification; a deoxidation label does not prove compliant grain size. If B and Ti are not deliberately added, B≤0.0007% and Ti≤0.01% apply. For 10B steels, follow notes B0.0008–0.003% and Ti≥0.01% of Table4; no unlisted Ti maximum is invented. Product-analysis deviations under Table5/8 and applicability conditions for 6.4 do not directly widen default heat limits. S1 permits relaxing residual Cr to 0.20 or Mo to 0.06 only when specified in the order. Lower residual limits require agreement; neither option is applied automatically in this batch. The original S2 explicitly cites the Nb/V grain-refinement rule of A29/A29M—15, requiring order specification and measured C/element results for the same heat; a newer A29 edition is not substituted. SAE/AISI in the original website title is only an existing product label. The grade in the composition source is IFI-10B38; equivalence to standard SAE/AISI is not claimed on that basis.