The invention consists of a gray cast iron comprising carbon, silicon, vanadium, manganese, nickel, chromium, molybdenum, copper, sulfur, phosphorous, tin and titanium, wherein: the percentage by weight of carbon is from 3.70 to 3.90%; the percentage by weight of silicon is from 1.30 to 2.10%; the percentage by weight of vanadium is from 0.10 to 0.15%; the percentage by weight of manganese is from 0.60 to 0.90%; the percentage by weight of nickel is from 0.05 to 0.50%; the percentage by weight of chromium is from 0.20 to 0.35%; the percentage by weight of molybdenum is no more than 0.10%; the percentage by weight of copper is no more than 0.35%; the percentage by weight of sulfur is less than 0.10%; the percentage by weight of phosphorous is less than 0.10%; the percentage by weight of tin is less than 0.10%; the percentage by weight of titanium is no more than 0.01%; the remainder by weight being iron.

The invention consists of a gray cast iron comprising carbon, silicon, vanadium, manganese, nickel, chromium, molybdenum, copper, sulfur, phosphorous, tin and titanium, wherein: the percentage by weight of carbon is from 3.70 to 3.90%; the percentage by weight of silicon is from 1.30 to 2.10%; the percentage by weight of vanadium is from 0.10 to 0.15%; the percentage by weight of manganese is from 0.60 to 0.90%; the percentage by weight of nickel is from 0.05 to 0.50%; the percentage by weight of chromium is from 0.20 to 0.35%; the percentage by weight of molybdenum is no more than 0.10%; the percentage by weight of copper is no more than 0.35%; the percentage by weight of sulfur is less than 0.10%; the percentage by weight of phosphorous is less than 0.10%; the percentage by weight of tin is less than 0.10%; the percentage by weight of titanium is no more than 0.01%; the remainder by weight being iron.

A diesel engine piston is cast in one piece and consists of almost fully pearlitic cast iron with spheroidal graphite as the piston material. Such a piston is used for “light vehicle” diesel engines, “heavy duty” diesel engines and “large bore” diesel engines.

A centrifugally cast composite roll for rolling comprising an outer layer and an inner layer, which are integrally fused to each other, the outer layer being made of an Fe-based alloy comprising by mass 1.70-2.70% of C, 0.3-3% of Si, 0.1-3% of Mn, 1.1-3.0% of Ni, 4.0-10% of Cr, 2.0-7.5% of Mo, 3-6.0% of V, 0.1-2% of W, 0.2-2% of Nb, 0.01-0.2% of B, and 0.01-0.1% of N, the balance being Fe and inevitable impurities, and the inner layer being made of ductile cast iron.

An iron-based alloy has excellent corrosion resistance and high strength and a method of manufacturing the iron-based alloy. The iron-based alloy includes Cr: 10 to 22 mass %, W: 1 to 12 mass %, and C: 0.1 to 2.3 mass %, with the remainder being unavoidable impurities and Fe, and is composed of a cast material having a structure composed mainly of austenite or a quenched material having a structure composed mainly of martensite and in which carbides are precipitated. The iron-based alloy may further include Cu: 0.5 to 6 mass % and/or Ni: 0.5 to 2.5 mass %, and may further include at least one of Al, Mo, and Si in an amount of 1 to 3 mass %.

An iron-based alloy has excellent corrosion resistance and high strength and a method of manufacturing the iron-based alloy. The iron-based alloy includes Cr: 10 to 22 mass %, W: 1 to 12 mass %, and C: 0.1 to 2.3 mass %, with the remainder being unavoidable impurities and Fe, and is composed of a cast material having a structure composed mainly of austenite or a quenched material having a structure composed mainly of martensite and in which carbides are precipitated. The iron-based alloy may further include Cu: 0.5 to 6 mass % and/or Ni: 0.5 to 2.5 mass %, and may further include at least one of Al, Mo, and Si in an amount of 1 to 3 mass %.

Bearing bushings which are exposed to highly elevated temperatures during operation, corresponding high-temperature-resistant bearing bushings and exhaust-gas turbochargers having at least one such bearing bushing, include an iron material having a material composition which, apart from iron, has at least carbon, silicon, manganese, nickel, chromium, molybdenum and tungsten alloy constituents in certain amounts. This material composition ensures sufficient temperature resistance and self-lubricating properties with simultaneously good machining properties and a moderate price.

Bearing bushings which are exposed to highly elevated temperatures during operation, corresponding high-temperature-resistant bearing bushings and exhaust-gas turbochargers having at least one such bearing bushing, include an iron material having a material composition which, apart from iron, has at least carbon, silicon, manganese, nickel, chromium, molybdenum and tungsten alloy constituents in certain amounts. This material composition ensures sufficient temperature resistance and self-lubricating properties with simultaneously good machining properties and a moderate price.

A self-lubricating rolling bearing is provided. The chemical compositions in the inner rings and the outer rings of bearing are 3.4-3.7% C, 2.7-2.9% Si, 0.3-0.5% Mn, 0.3-0.5% Cr, ≤0.05% S, ≤0.05% P, 0.03-0.045% Residual Mg, and the remainder Fe. The total percent of the chemical compositions is 100%. The material for the inner and outer rings of the rolling bearing introduced in the invention is austempered ductile iron (ADI). In the microstructure of ADI, the diameter of the graphite nodules is less than 0.02 mm, the number of graphite spheres per square millimeter is more than 400, and the microstructure of the metal matrix in the ADI can be showed clearly only when it is observed on the microscope with a magnification more than 500. Eventually, the self-lubricating rolling bearings are made from the ADI.

A self-lubricating rolling bearing is provided. The chemical compositions in the inner rings and the outer rings of bearing are 3.4-3.7% C, 2.7-2.9% Si, 0.3-0.5% Mn, 0.3-0.5% Cr, ≤0.05% S, ≤0.05% P, 0.03-0.045% Residual Mg, and the remainder Fe. The total percent of the chemical compositions is 100%. The material for the inner and outer rings of the rolling bearing introduced in the invention is austempered ductile iron (ADI). In the microstructure of ADI, the diameter of the graphite nodules is less than 0.02 mm, the number of graphite spheres per square millimeter is more than 400, and the microstructure of the metal matrix in the ADI can be showed clearly only when it is observed on the microscope with a magnification more than 500. Eventually, the self-lubricating rolling bearings are made from the ADI.