China leads new ISO standard on power conductor corrosion

China has led the development of a new international standard for corrosion testing of conductive materials used in power transmission systems, marking a significant step forward in global grid safety and reliability.

The standard, titled "Corrosion of metals and alloys – Testing methods for corrosion of conducting alloys in AC electric current condition," was officially published by the International Organization for Standardization (ISO) recently.

With the total length of power transmission and distribution lines worldwide now exceeding 80 million kilometers, conductive materials such as copper, aluminum and their alloys are extensively used in transmission cables and associated hardware. During live operation, alternating current, fluctuating electromagnetic fields and atmospheric corrosion agents interact in ways that can significantly accelerate material degradation.

In coastal and heavily industrialized regions, corrosion has become a major challenge for grid operators. More than 30% of overheating and fracture incidents in conductor materials are directly linked to corrosion, making it one of the key threats to the long-term safe operation of power infrastructure.

The standard specifies seven critical parameters, including power supply type, output power, sample dimensions, surface treatment methods, circuit configuration, testing duration and temperature conditions. It simulates the electromagnetic field distribution on transmission conductors operating at frequencies of 50 or 60 hertz, enabling more realistic corrosion kinetics and corrosion rate measurements.

The standard is expected to support more precise corrosion prediction, differentiated anti-corrosion strategies and service-life assessments for transmission equipment. It could help reduce maintenance and operational costs by more than 10%.

The release of the standard highlights growing international recognition of China's technical capabilities in corrosion testing for power conductor materials. It is also expected to support the development of strategic emerging industries, including advanced materials and smart power grids, while contributing to the safer and more stable operation of global energy infrastructure.