... investment castingKey specification1.Material: stainless steel, carbon steel, alloy steel ,iron ,alloy, 2.Standard: ASTM\DIN\BS\JIS3.Surface finish: passivated ... machine, polishing machine.Heat treatmentannealing, termpering, quenching, normalizing, solid solution.Testing facilityspectrometer, tensile test machine, hardness test machine, mircoscope. China Marine Hardware/steel part-made in China