Citation: B˘ ail˘ a, D.-I.; P ˘ acurar, R.; Savu, T.; Zaharia, C.; Trus , c˘ a, R.; Nemes , , O.; Górski, F.; P˘ acurar, A.; Ples , a, A.; Sab ˘ au, E. Mechanical and Wetting Properties of Ta 2 O 5 and ZnO Coatings on Alloy Substrate of Cardiovascular Stents Manufactured by Casting and DMLS. Materials 2022, 15, 5580. https://doi.org/10.3390/ ma15165580 Academic Editor: Csaba Balázsi Received: 28 July 2022 Accepted: 12 August 2022 Published: 14 August 2022 Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affil- iations. Copyright: © 2022 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/). materials Article Mechanical and Wetting Properties of Ta 2 O 5 and ZnO Coatings on Alloy Substrate of Cardiovascular Stents Manufactured by Casting and DMLS Diana-Irinel Băilă 1, * ,Răzvan Păcurar 2, * , Tom Savu 1 ,Cătălin Zaharia 3 , Roxana Trus , că 4 , Ovidiu Nemes , 5 , Filip Górski 6 , Ancut , aPăcurar 2 , Alin Ples , a 7 and Emilia Sabău 2 1 Department of Manufacturing Engineering, Faculty of Industrial Engineering and Robotics, University Politehnica of Bucharest, Blv. Splaiul Independent , ei, No. 313, Sector 6, 060042 Bucharest, Romania 2 Department of Manufacturing Engineering, Faculty of Industrial Engineering, Robotics and Production Management, Technical University of Cluj-Napoca, Blv. Muncii, No. 103-105, 400641 Cluj-Napoca, Romania 3 Advanced Polymer Materials Group, Department of Bioresources and Polymer Science, University Politehnica of Bucharest, 1-7 Gh. Polizu Street, 011061 Bucharest, Romania 4 Department of Science and Engineering of Oxide Materials and Nanomaterials, Faculty of Applied Chemistry and Materials Science, University Politehnica of Bucharest, Blv. Splaiul Independent , ei, No. 313, Sector 6, 060042 Bucharest, Romania 5 Department of Environmental Engineering and Sustainable Development Entrepreneurship, Faculty of Materials and Environmental Engineering, Technical University of Cluj-Napoca, Blv. Muncii, No. 103-105, 400641 Cluj-Napoca, Romania 6 Faculty of Mechanical Engineering, Poznan University of Technology, 60-965 Poznan, Poland 7 Department of Mechatronics and Machine Dynamics, Faculty of Automotive, Mechatronics and Mechanical Engineering, Technical University of Cluj-Napoca, Blv. Muncii, No. 103-105, 400641 Cluj-Napoca, Romania * Correspondence: baila_d@yahoo.com (D.-I.B.); razvan.pacurar@tcm.utcluj.ro (R.P.) Abstract: In the last years, additive manufacturing technologies have been developed, especially direct metal laser sintering, and used in the dental and medical implant domains. Cardiovascular stents have evolved from bioinert, bare metal cages to biomimetic devices that promote tissue re- generation or healing. In this paper, comparisons concerning mechanical properties between Co–Cr alloy and cast 304L stainless steel were realized using FEM analysis, necessary for manufacturing cardiovascular stents by DMLS technology using Co–Cr alloy. The purpose of this paper consists of the evaluation of the contact angle at the interface of the Co–Cr alloy manufactured by DMLS, respec- tively, cast stainless steel 304L, and thin film deposition realized by the e-gun method (Ta 2 O 5 and ZnO). Scanning electronic microscopy SEM and EDX techniques were employed for morphological investigation of the sintered samples manufactured by the DMLS process. They were also used for semi-quantitative and qualitative chemical and metallographic analyses. The e-gun coating was used to obtain thin films with the nanometer order of Ta 2 O 5 and ZnO with a protective role to improve the corrosion resistance, roughness, and antiseptic role. Keywords: thin films; DMLS process; contact angles; mechanical simulations; cardiovascular stents 1. Introduction Additive manufacturing technology has realized a real medical revolution due to the manufacturing possibilities and the various materials that can be used, from plastic, ceramic to metallic alloys. These technologies permit the manufacture, in a very short time, of various special prostheses with complex shapes, personalized implants or customized devices for each patient depending on the disease. This technology is used frequently in the dental, orthopedic and in surgery domains [1–3]. Cardiovascular stents are used in angioplasty surgery and are used to open blocked coronary arteries caused by coronary artery disease. Angioplasty is recommended in an emergency setting such as a heart attack. Pan. C. considered that, in angioplasty, a catheter, Materials 2022, 15, 5580. https://doi.org/10.3390/ma15165580 https://www.mdpi.com/journal/materials