TY - JOUR
T1 - Evaluation of cold-sprayed CuCr coatings as contact materials for vacuum interrupters
AU - Koneru, Animesh
AU - Karmarkar, Neeraj
AU - Wang, Yaping
AU - Mohanty, Pravansu S.
AU - Li, Ben Q.
N1 - Publisher Copyright:
© 2023 Elsevier Ltd
PY - 2023/10
Y1 - 2023/10
N2 - In the present study, cold-sprayed copper-chromium (CuCr) coatings are investigated as an alternative to traditional CuCr composites which are used in medium voltage vacuum interrupters (VIs). Test samples for this study are produced by depositing coatings on copper substrates using pre-mixed Cu and Cr powders with N2 as main gas, at two different pressures. As-sprayed CuCr coatings exhibited high porosity and poor Cu/Cr interfacial bonding when deposited at 2.25 MPa, and lower Cr retention within the coatings when deposited at 3.45 MPa. Electrical resistivity and hardness of CuCr coatings are measured, and compared with bulk CuCr composites which are produced by the conventional press-sinter-infiltration (PSI) method. Cold-sprayed coatings having higher porosity exhibited inferior electrical properties when compared to PSI samples with comparable Cr content. Furthermore, the coatings are subjected to electrical arcs in a vacuum chamber to establish vacuum breakdown characteristics. As sprayed CuCr coatings have lower breakdown strength but similar arc-life, when compared to PSI samples. Finally, considerable differences are observed in arc mode on the surface of CuCr coatings compared to PSI samples. Vacuum arc erosion morphology on the samples studied using SEM, show scattered arc-erosion zones and higher depth erosion craters for CuCr coatings. Through the annealing studies conducted on CuCr coatings at 200°C and 425°C, improvements were observed in the electrical resistivity and vacuum breakdown strength of the coatings. These improvements brought the properties of the annealed CuCr coatings to a level comparable to the PSI samples.
AB - In the present study, cold-sprayed copper-chromium (CuCr) coatings are investigated as an alternative to traditional CuCr composites which are used in medium voltage vacuum interrupters (VIs). Test samples for this study are produced by depositing coatings on copper substrates using pre-mixed Cu and Cr powders with N2 as main gas, at two different pressures. As-sprayed CuCr coatings exhibited high porosity and poor Cu/Cr interfacial bonding when deposited at 2.25 MPa, and lower Cr retention within the coatings when deposited at 3.45 MPa. Electrical resistivity and hardness of CuCr coatings are measured, and compared with bulk CuCr composites which are produced by the conventional press-sinter-infiltration (PSI) method. Cold-sprayed coatings having higher porosity exhibited inferior electrical properties when compared to PSI samples with comparable Cr content. Furthermore, the coatings are subjected to electrical arcs in a vacuum chamber to establish vacuum breakdown characteristics. As sprayed CuCr coatings have lower breakdown strength but similar arc-life, when compared to PSI samples. Finally, considerable differences are observed in arc mode on the surface of CuCr coatings compared to PSI samples. Vacuum arc erosion morphology on the samples studied using SEM, show scattered arc-erosion zones and higher depth erosion craters for CuCr coatings. Through the annealing studies conducted on CuCr coatings at 200°C and 425°C, improvements were observed in the electrical resistivity and vacuum breakdown strength of the coatings. These improvements brought the properties of the annealed CuCr coatings to a level comparable to the PSI samples.
KW - Arc-erosion resistant materials
KW - Cold spray coatings
KW - Copper–chromium composites
KW - CuCr coatings
KW - CuCr contacts
KW - Vacuum interrupter contacts
UR - https://www.scopus.com/pages/publications/85165353557
U2 - 10.1016/j.vacuum.2023.112384
DO - 10.1016/j.vacuum.2023.112384
M3 - 文献综述
AN - SCOPUS:85165353557
SN - 0042-207X
VL - 216
JO - Vacuum
JF - Vacuum
M1 - 112384
ER -