Vermicular graphite cast iron grades

Vermicular graphite cast iron grades The interstate standard GOST 28394-89 regulates this. According to these regulations, the amount of spheroidal graphite must not exceed 40%, which imparts specific mechanical properties to the material. This standard specifies the following grades of ChVG: ChVG30, ChVG35, ChVG40, and ChVG45. ChVG, respectively, designates cast iron with vermicular graphite. The subsequent numbers indicate the tensile strength; for example, ChVG35 has a minimum tensile strength of 350 MPa.

ChVG 30, 35, and 40 grades are used for general engineering components subject to increased variable mechanical loads—components for internal combustion engines; automotive, tractor, shipbuilding, diesel engine, and metallurgical equipment. ChVG 45 grade is used for components operating under increased mechanical loads, where there is high friction, and therefore wear, and under increased thermal cycling loads.

Listed grades of cast iron with vermicular graphite It is also successfully used for the production of brake discs for high-speed trains, covers, cylinder heads for powerful marine and diesel locomotive engines, molds, chill mold equipment, and also for the production of screw gear housings and high-pressure hydraulic equipment.

Various grades of cast iron with vermicular graphite They differ primarily in chemical composition. Here are several grades and their compositions (data are given in % alloy mass fraction):

ChVG 30: Carbon 3.5-3.8%, Silicon 2.2-3.0%, Manganese 0.2-0.6%, Phosphorus Up to 0.08%, Sulfur Up to 0.025%, Chromium Up to 0.15%, Copper — , Magnesium 0.015 0.028* 0.10-0.20;

ChVG 35: Carbon 3.5-3.8%, Silicon 2.2-2.8%, Manganese 0.2-0.6%, Phosphorus Up to 0.08%, Sulfur Up to 0.025%, Chromium Up to 0.15%, Copper — , Magnesium 0.02-0.028 0.10-0.20;

ChVG 40: Carbon 3.1-3.5%, Silicon 2.0-2.5%, Manganese 0.4-1.0%, Phosphorus Up to 0.08%, Sulfur Up to 0.025%, Chromium Up to 0.20%, Copper 0.4-0.6%, Magnesium 0.02-0.028 0.10-0.20;

ChVG 45**: Carbon 3.1-3.5%, Silicon 2.0-2.5%, Manganese 0.8-1.2%, Phosphorus Up to 0.05%, Sulfur Up to 0.025%, Chromium Up to 0.30%, Copper 0.8-1.0%, Magnesium 0.02-0.028 0.10-0.20.