High-temperature oxidation-resistant wear-resistant grey cast iron and preparation method thereof

Abstract

The invention provides high-temperature oxidation-resistant wear-resistant grey cast iron and a preparation method thereof. The high-temperature oxidation-resistant wear-resistant grey cast iron is prepared from the following components in percentages by mass: 3.35-3.6% of carbon, 1.6-1.8% of silicon, 1.15-1.25% of manganese, 0.3-0.4% of molybdenum, 0.5-0.8% of molybdenum, 0.5-1.3% of boron, 0.005-0.012% of nitrogen, 0.4-1.2% of aluminum, 0.05-0.2% of niobium, 0.05-0.2% of titanium and the balance of iron and inevitable impurities. The high-temperature oxidation-resistant wear-resistant grey cast iron provided by the invention is prepared by the steps of smelting, pouring, quenching, tempering and the like, has excellent mechanical properties and wear resistance and is high in heat fatigue resistance and high-temperature oxidation resistance, and the problem that in the prior art, the grey cast iron is low in hardness, low in tensile strength and weak in high-temperature oxidation resistance is solved.

Description

technical field [0001] The invention relates to the technical field of cast iron, in particular to a high-temperature oxidation-resistant and wear-resistant gray cast iron and a preparation method thereof. Background technique [0002] Gray cast iron refers to cast iron with flake graphite. When it breaks, the fracture is dark gray. The main components are iron, carbon, silicon, manganese, sulfur and phosphorus. It is the most widely used cast iron, and its output accounts for more than 80% of the total output of cast iron. The mechanical properties of gray cast iron are related to the structure of the matrix and the morphology of graphite. The flake graphite in gray cast iron severely splits the matrix, and it is easy to cause stress concentration at the sharp corners of graphite, so that the tensile strength, plasticity and toughness of gray cast iron are far lower than steel, but the compressive strength is equivalent to steel, and it is also commonly used in cast iron. ...

AI Technical Summary

Problems solved by technology

The flake graphite in gray cast iron severely splits the matrix, and it is easy to cause stress concentration at the sharp corners of graphite, so that the tensile strength, plasticity and toughness of gray cast iron are far lower than steel, but the compressive strength is equivalent to steel, and it is also commonly used in cast iron. Cast iron with the worst mechanical properties in parts

At the same time, the matrix structure also has a certain influence on the mechanical properties of gray cast iron. The graphite flakes of gray cast iron with ferrite matrix are thick, with the lowest strength and hardness, so they are rarely used; the graphite flakes of gray cast iron with pearlite matrix are fine and have high Strength and hardness, mainly used to make more important castings; graphite flakes of ferrite-pearlite matrix gray cast iron are slightly thicker than pearlitic gray cast iron, and the performance is not as good as pearlitic gray cast iron

At present, the existing gray cast iron has poor mechanical properties and low hardness. It is easily oxidized under high temperature conditions for a long time and has a short service life.

Images