Meaning
Surface degradation process occurring when metals react with oxygen at elevated temperatures defines the operational lifetime of superalloy turbine blades. In high temperature oxidation, a protective oxide scale must form to shield the substrate from further environmental damage. The Ministry of Industry and Information Technology (MIIT) sets strict degradation limits for materials used in energy plants.
These regulations ensure that all generation components survive their planned operational cycles without mechanical failure.
Degradation Mechanism
Thermal exposure in oxygen-rich environments leads to rapid chemical reaction on the alloy surface. When high temperature oxidation occurs, the transport of oxygen inward and metal ions outward governs the scale growth rate. This kinetic rate must remain low to prevent premature metal thinning.
Quality Verification
Compliance audits conducted by the State Administration for Market Regulation (SAMR) check the oxidation resistance of batch metals. National GB/T standards mandate specific isothermal test cycles to measure the mass change of alloys over time. Factories that fail these standards cannot distribute their alloy stocks to aerospace state-owned enterprises.
Operational Limit
Materials showing rapid scaling or oxide spallation during testing are disqualified from import under GACC inspection rules. Foreign suppliers must provide multi-hundred-hour test logs to secure commercial clearance. These regulations protect domestic thermal power infrastructure.
