Materials Development for Indian Nuclear Power Programme: an Industry Perspective

Materials play very crucial role for a safe, reliable and economic operation of nuclear power plants. Materials used in nuclear reactors encounter hostile environment and aggressive media during service, and are expected to retain their structural and metallurgical integrity over a long period of use. The major challenges are the effect of radiation on embrittlement, creep, erosion, corrosion, radiation induced growth, swelling, stress corrosion cracking, hydrogen embrittlement and radioactivity build up. In order to realize a high degree of reliabilit y and at the same time meet the imposing challenges, material specification and acceptance criteria are extremely stringent and the products have to undergo a detailed testing and characterization prior to their use. To ensure the conformance to the specification, processes need to be developed which involves melting the alloy with stringent chemistry control, optimizing thermo-mechanical treatment and modifying heat treatment schedule suitably to achieve mechanical properties.A typical nuclear power plant makes use of nuclear fuel materials such as uranium, structural materials such as zirconium alloys, stainless steels, nickel base alloys as well as low alloy and carbon steels. The paper outlines processing methodologies and gives an overview of some of the structural materials.