Abstract A novel spectrally selective multilayer coating: Cr-(CrN/TiAlN)m-AlSiN-AlSiO on SS316 substrate/tube was deposited via Cathodic Arc Physical Vapor Deposition (CAPVD) technique. The coating exhibited state-of-the-art absorptivity (α = 0.95–0.96) and emissivity (e = 0.09–0.11). In view of open-air solar thermal application requirements, the coating has been systematically analysed for its thermal, environmental (corrosion) and mechanical stability. The thermal cycling studies carried out at 500 °C in open-air conditions have shown no change in optical properties for about 150 cycles. Further, accelerated thermal aging tests have shown an extrapolated service life of 25 years at 411 °C. In the case of corrosion studies, up to 520 h of exposure to 5% NaCl medium, no considerable change in optical properties was observed. Further, the coatings were well adherent to the substrates/tubes (6 N of critical load) with a considerable hydrophobicity (104° contact angle). The observed results indicate that, Cr-(CrN/TiAlN)2–AlSiN–AlSiO coating may be a good choice for developing receiver tubes used in Concentrated Solar Power (CSP) systems with best solar selective properties and the capability to withstand harsh environments like solar flux variations, thermal shocks in the presence of open-air pollutants, dust and humidity.

中文翻译：

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用于集中太阳能热发电应用的 Cr-(CrN/TiAlN)m-AlSiN-AlSiO 露天稳定太阳能选择性涂层

摘要 通过阴极电弧物理气相沉积 (CAPVD) 技术在 SS316 基板/管上沉积了一种新型光谱选择性多层涂层：Cr-(CrN/TiAlN)m-AlSiN-AlSiO。该涂层表现出最先进的吸收率（α = 0.95-0.96）和发射率（e = 0.09-0.11）。鉴于露天太阳能热应用的要求，已对涂层的热稳定性、环境（腐蚀）和机械稳定性进行了系统分析。在露天条件下在 500 °C 下进行的热循环研究表明，约 150 次循环后光学特性没有变化。此外，加速热老化测试表明，在 411 °C 下的使用寿命为 25 年。在腐蚀研究的情况下，暴露于 5% NaCl 介质长达 520 小时，没有观察到光学特性的显着变化。更多，涂层与基材/管（6 N 的临界载荷）良好粘附，具有相当大的疏水性（104° 接触角）。观察结果表明，Cr-(CrN/TiAlN)2–AlSiN–AlSiO 涂层可能是开发用于聚光太阳能 (CSP) 系统的接收管的不错选择，具有最佳太阳能选择性和耐受恶劣环境的能力，例如太阳通量变化、露天污染物存在时的热冲击、灰尘和湿度。