Erosion-oxidation interaction in Ni and Ni-20Cr alloy

Abstract

The solid-particle erosion of metals and alloys at elevated temperatures is characterized by different mechanisms of material removal, depending on the temperature of exposure, impact velocity, impact angle, and flux rate of the eroding particles. The objective of this article is to delineate the prevalent erosion mechanisms in nickel and a nickel-20 chromium alloy over a large range of temperatures, impact velocities, impact angles, and particle feed rates. For this purpose, a specialized elevatedtemperature erosion rig has been utilized. Nickel and a Ni-20Cr alloy have been chosen as the test materials, in view of their substantially different oxidation behaviors. Results from the present study indicate that while the erosion rate generally increases with increasing temperature, an increased particle feed rate causes a reduction in the erosion rate, especially at higher temperatures beyond 650 K. On the basis of a detailed examination of the morphology of the eroded surfaces and the subsurface features beneath the eroded surfaces, four different material removal mechanisms have been identified in the nickel, while only three material removal mechanisms were operative in the Ni-20Cr alloy. Utilizing the aforementioned information, erosion-oxidation (E-O) interaction mechanism maps (herein, termed E-O maps) delineating the regions of dominance of the various erosion mechanisms in an impact velocity-test temperature space have been constructed for Ni and a Ni-20Cr alloy. Finally, the differences in erosion behavior between the Ni and Ni-20Cr alloy have been identified and rationalized.

Effect of mating surface on the high temperature wear of 253 MA alloy

“…9). This leads to the formation of a thick hard composite layer, which is similar to the layer reported by Roy et al [21] for solid particle erosion of metallic materials or the glased layer observed by Stott and Jordan [11] and Jiang et al [8]. This layer is not very adherent to the specimen.…”

Axial Plasma Spraying of Mixed Suspensions: A Case Study on Processing, Characteristics, and Tribological Behavior of Al2O3-YSZ Coatings

“…The ratio of erosion rates at impact angles of 90 • and 30 • , E90/E30, is an indicator of the nature of erosion, with values less than 0.5 being suggestive of ductile behavior and values greater than 1 implying brittle behavior [46,47]. Compared to pure Al 2 O 3 coatings which are known to exhibit E90/E30 ratio greater than 2 [22], the E90/E30 values for the SPS Al 2 O 3 -YSZ coatings were found to be in the range of 1.2-1.4.…”

Hochtemperatur-Verschleißverhalten von Ein- und Mehrphasenwerkstoffen

“…Typische Anwendungs beispiele hierfür sind Zerkleinerungseinrichtungen für Sinterkuchen in der Stahlindustrie oder Förder-schnecken. Auch ist durch die erhöhte Anwendungstemperatur der Einfluss von Oxidation auf die Verschleißteile zu berücksichtigen [1][2][3] …”