INGERSOLL ISO MATERIAL GROUPS (CONT.) ISO Material Condition Tensile Hardness MaterialStrength (Kpsi)HBNumber Non - Alloy Steels <0.25% C Annealed 61 125 1 Steel Castings =>0.25% C Annealed 94 190 2 Free Machining Steel <0.55% C Quenched & Tempered 123 250 3 =>0.55% C Annealed 109 220 4 =>0.55% C Quenched & Tempered 145 300 5 P Low - Alloy Steels and Steel Castings Annealed 87 200 6 (less than 5% of alloying elements) 135 275 7 Quenched & Tempered 145 300 8 174 350 9 High - Alloy Steels, Steel Annealed 99 200 10 Castings & Tool Steels Quenched & Tempered 160 325 11 Stainless Steels and Ferritic/Martensitic 99 200 12 M Stainless Steel Castings Martensitic 119 240 13 Austenitic & P.H. 87 180 14 Nodular Cast Iron (GGG) Ferritic / Pearlitic 180 15 Pearlitic 260 16 K Grey Cast Iron (GG) Ferritic 160 17 Pearlitic 250 18 Malleable Cast Iron Ferritic 130 19 Pearlitic 230 20 Aluminum wrought alloy As cast 60 21 Forged 100 22 Cast Aluminum alloyed <=12% Si As cast 75 23 Forged 90 24 N > 12% Si High Temperature 130 25 Free Cutting 110 26 Copper Alloys Brass 90 27 Electrolitic Copper 100 28 Non Metallic Duroplastics & Fiberplastics 29 Hard Rubber 30 Fe Based Annealed 200 31 Cured 280 32 S High Temp Alloys Ni or Co BasedAnnealedCured 250 3335034 Cast 320 35 Titanium and Ti Alloys 58 36 Alpha+Beta alloys cured 152 37 Hardened Steel 55 HRc 38 H Chilled Cast Iron Cast 60 HRc 3940040 Cast Iron Hardened 55 HRc 41 670