Improvement of Corrosion and Wear Resistance of CoCrNiSi0.3 Medium-Entropy Alloy by Sputtering CrN Film

Abstract

In this study, Co, Cr, and Ni were selected as the equal-atomic medium entropy alloy (MEA) systems, and Si was added to form CoCrNiSi0.3 MEA. In order to further improve its wear and corrosion properties, CrN film was sputtered on the surface. In addition, to enhance the adhesion between the soft CoCrNiSi0.3 substrate and the super-hard CrN film, a Cr buffer layer was pre-sputtered on the CoCrNiSi0.3 substrate. The experimental results show that the CrN film exhibits a columnar grain structure, and the film growth rate is about 2.022 μm/h. With the increase of sputtering time, the increase in CrN film thickness, and the refinement of columnar grains, the wear and corrosion resistance improves. Among all CoCrNiSi0.3 MEAs without and with CrN films prepared in this study, the CoCrNiSi0.3 MEA with 3 h-sputtered CrN film has the lowest wear rate of 2.249 × 10−5 mm3·m−1·N−1, and the best corrosion resistance of Icorr 19.37 μA·cm–2 and Rp 705.85 Ω·cm2.

Microstructure, material characteristics and mechanical properties of CoMoNiTa3 medium-entropy alloys through the vacuum hot pressing process

“…where F is the maximum fracture load, L is 30 mm, k is the chamfer correction factor (normally 1.00-1.02) and b and h are 5 mm, respectively. The specimen dimensions of the TRS test were 5 × 5 × 40 mm 3 . Moreover, each datum measured at least three samples to get the average value.…”

“…14 These results demonstrate that hot-pressed medium-entropy alloys indeed possess superior mechanical properties, aligning with the advantages highlighted in the previous literature. [1][2][3] EPMA, EBSD and TEM observations of vacuum hot-pressing CoMoNiTa 3 alloys According to the above discussion and test results, this study further investigated the microstructural characteristics of the optimal hot-pressing parameters of the CoMoNiTa 3 specimens. Figure 8 shows the EPMA-mapping analysis for the CoMoNiTa 3 medium-entropy alloys after 1100 °C HP at 50 MPa for 1 h, where the Co and Ni were almost completely dissolved in the matrix phase.…”

“…These alloys consisting of multiprincipal elements are changing the traditional definition of metallurgical alloys and exploring the unknown territories of alloy design. [1][2][3] Compared to traditional singlecomponent alloys, HEAs and MEAs with unique high entropy effects have attracted considerable attention in recent years. [1][2][3][4] Currently, most developing CoCrNi [5][6][7] and CoMoNi 8,9 MEAs possess excellent strength, good hardness and outstanding wear resistance; thus, they have attracted wide attention.…”

“…[1][2][3] Compared to traditional singlecomponent alloys, HEAs and MEAs with unique high entropy effects have attracted considerable attention in recent years. [1][2][3][4] Currently, most developing CoCrNi [5][6][7] and CoMoNi 8,9 MEAs possess excellent strength, good hardness and outstanding wear resistance; thus, they have attracted wide attention. Typically, above-MEA alloys are prepared by casting techniques that require long-term melting and homogenisation treatments.…”

“…These alloys consisting of multi-principal elements are changing the traditional definition of metallurgical alloys and exploring the unknown territories of alloy design. 1–3 Compared to traditional single-component alloys, HEAs and MEAs with unique high entropy effects have attracted considerable attention in recent years. 1–4…”