... , alloy steel . Tooth hearttreatment :Carburization or Ion nitrification Gear class :AGMA12 Spiral Bevel Gear for gear box 1) Material: 42CrMo, 35CrMo, 17CrNiMo , 20CrMnMo, 20Cr2Ni4, , 20CrMnTi ... deep 0.7-1mm Other hearttreatment according client request . 3) Gear class : Grade V or AGMA12 ( tooth surface grinding )Machiness ... 's drawing and samples are welcome crown wheel and pinion for gear box