Abstract
Superconducting wires and tapes are key enabling materials for high-field magnets, nuclear fusion, superconducting power systems and medical imaging. In practical conductors fabricated by the powder-in-tube (PIT) method, the precursor powder is not merely a starting material; it establishes the chemical, microstructural and processing conditions that govern phase formation, texture, density, connectivity and ultimately the critical current density. The challenge is therefore to develop precursor powders that deliver high superconducting performance while remaining compatible with stable, cost-effective and scalable wire and tape manufacturing. This review examines the preparation of precursor powders for practical BSCCO, MgB2 and 122-type iron-based superconductors. We first clarify the functions and evaluation criteria of precursor powders, and then compare the principal synthesis routes and powder-modification strategies used for these conductor systems. Particular attention is given to the links between composition, impurity phases, particle characteristics, reactivity, heat-treatment windows and the resulting conductor properties. We further discuss how non-uniformity and process sensitivity of powders can hinder batch consistency and obstruct scale-up. Overall, the evidence shows that progress must go beyond particle-size refinement or reactivity enhancement alone. A more useful target is an engineering-oriented powder system with precise composition, controllable phase composition, designable particle structure, a matched heat-treatment window and robust production yield. Such powder design, coupled with conductor process optimization, provides a practical path toward higher-performance and more reliable superconducting wires and tapes.