... are welcomed 4.Investment casting with heat treatment casting steel auto parts Quality System CertificateISO 9001Dimension ToleranceCT7Surface RoughnessRa6.4~12.5Casting Weight0 ... Composition Analysis, Tensile Test, Dimension Inspection, Hardness TestingSurface TreatmentHeat Treatment, Machine, Polishing, Chrome, Zinc, Nickel PlatingPackingCartons, Wooden Case, Steel Cases, PalletsAdvantage1 ...