Research Progress of High-Temperature Thin-Film Strain Gauges: A Review

High-temperature thin-film strain gauges (HTFSGs) hold significant potential for monitoring extreme environments in fields such as aerospace, nuclear energy, and automotive engineering. With advances in materials science, HTFSGs based on ceramics, metals, and composite materials have progressively achieved high-precision strain measurements in high-temperature environments. In recent years, substantial progress has been made in areas such as material selection, sensor structural optimization, high-temperature oxidation resistance, and testing methodologies, which have enhanced the stability, sensitivity, and durability of HTFSGs under extreme conditions. This article reviews the developmental trajectory of HTFSGs research, focusing on the strain mechanisms of sensitive materials and recent advancements in ceramic-metal thin films, ceramic-semiconductor thin films, and metal-based thin films for HTFSGs in terms of structural design, thin-film deposition processes, and material properties. Additionally, current challenges and future research directions are discussed to provide valuable insights for future studies.