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The curved surfaces conformality has become the coming barrier to the implementation of the metasurface carpet cloaks. A curved conformal strategy that can balance the electromagnetic performances and the manufacturing challenges of metasurface simultaneously is highly in demand, but yet underexplored. Herein, a novel thermal programming 3D‐printing method for curved conformal metasurface is proposed. Owing to the glass‐rubber transition characteristics of thermoplastic polymers, the advantages of rigid substrate and flexible substrate are fully utilized to achieve the conformality of metasurface, which ingeniously reduces the manufacturing complexity and ensures the electromagnetic performances. As a proof, an arched metasurface carpet cloak composed of the easy‐bending unit cells is designed and fabricated by the composite fused deposition molding of polylactic acid and Sn‐Bi materials with the thermal programming process. Experiments prove that the maximum reduced total radar cross section of the conformal cloak reaches about −9.4 dB while the 3 dB reduction bandwidth is ≈26.6%. The excellent cloaking performance of the metasurface sample demonstrates the effectiveness of this curved conformal method. This work provides a viable implementation strategy for complex curved metasurface and will substantially promote the applications of the conformal invisibility cloaks. [ABSTRACT FROM AUTHOR]

[Display omitted] • A complex gradient composite metastructure was fabricated by 3D printing technology. • This metastructure has the broadband and strong microwave absorption. • Maintaining broadband absorption under wide-angle for different polarization. • Low loss materials addition could satisfy the high-performance microwave absorption. Gradient composite metastructures have been demonstrated in effectively improving the microwave absorbing performance. However, the preparation of the complex structures still remains challenging. Herein, a complex gradient composite microwave absorbing metastructure is designed and fabricated by the low cost, high-efficiency fused deposition modeling of 3D printing technologies. The metastructure is composed of flaky carbonyl iron particles and Polyether-ether-ketone composite which demands only 50% loss material mass addition. Structural parameters are investigated and optimized for absorbing bandwidth and reflectivity intensity. Simulations and experiments demonstrate that the designed complex gradient metastructure with the thickness of 10 mm can achieve the −10 dB absorbing bandwidth in the frequency range from 5.1 to 40 GHz, and the absorbing bandwidth corresponding to −15 dB in 7.7–14.7 GHz and 22.6–36.3 GHz. Meanwhile, this metastructure also can maintain the broadband and strong microwave absorption with incident angle from 0° to 55° for transverse electric polarization and 0° to 70° for transverse magnetic polarization. Moreover, the proposed metastructure is also demonstrated with good compression strength which shows preferable mechanical stability. This work provides a simple and promising route of broadband and wide-angle microwave strong absorption for practical application. [ABSTRACT FROM AUTHOR]