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Nickel-based superalloys are used widely in the critical areas of applications such as aerospace, marine, power and many process industries. In this study, solid particle erosion behavior of cast nickel-based CY5SnBiM was analyzed at room temperature. The velocity and angle of the study were set to 59 m/s, 92 m/s and 124.137 m/s, and 30°, 45°, 60° and 90°, respectively; this resembles the exact industrial valve applications. Macrographs were taken to identify the wear scar of material at different angles and different velocities. X-ray diffraction (XRD) was carried out on the material to observe the nature of precipitates. Scanning electron microscopy (SEM) was carried out to identify the plowing action on the material by the erodent in the case of lower angle due to ductile nature of the material. In the case of higher angle, it develops deep pits and craters due to rebounding of erodent particles.

Aluminium composite with VAL12 as matrix and La2O3 as dispersoids fabricated through liquid metallurgy route involving liquid forging operation through squeeze casting process in the present investigation. The frictional characteristics of as-cast aluminium composites are studied under dry sliding wear tests by varying the service factors. The samples prepared were examined for its uniform distribution of the reinforcement, phases formed using advanced characterization facilities. Taguchi orthogonal array method is employed in designing the experiments, and the responses are recorded in terms of wear rate and frictional coefficient. The mechanistic studies are carried out by analyzing the wear surface morphology using SEM. Predominantly AMMC shows delamination and abrasion at higher loads due to thermal softening and adhesive mechanisms at lower loads. Load and sliding distance majorly characterize the wear behavior of the AMMCs under un-lubricated sliding conditions.

Duplex stainless steel (DSS) is having an equal fraction of ferrite and austenite. Chromium, Nickel, Molybdenum, and few minor alloying elements constitute a DSS system, which makes metallurgy of the system complex. Proper heat treatment is need of the hour when it comes to expecting desired properties from the material, subjected to a specific working environment. DSS is one of the favourite choices for oil and gas industries. This study focuses on optimizing the heat treatment parameters and heat treating the as-cast 5A DSS and investigating microstructural evolution of the material subjected to various quenchants such as brine, water, and polyethylene glycol. Heat treatment temperatures, quenching media, and the quenching time have been selected in accordance with ASTM standards. Thermocalc TCFE8 database is being used for understanding the material response to various heat treating temperatures.

Niobium addition to base alloy significantly reduces the formation of deleterious phases, in particular, sigma phase when the material is sensitized at 900 °C. In this paper, hyper-duplex stainless steel with 0.47% of Niobium (Nb + CD3MWN - 7A) was casted using induction melting furnace and then heat-treated under two different heat treatment temperatures of 1160 °C and 900 °C to explore the properties such as microstructure and hardness for further study. The erosion test was carried out in air-jet erosion tester at room temperature with different erodent velocities. The study was done with a constant impact angle of 45°. Microstructure analysis was carried on two different heat-treated samples as well as on eroded samples using scanning electron microscope coupled with energy-dispersive analysis spectroscopy to confirm the presence Niobium carbide precipitation in sensitized sample at grain boundaries. Erosion test results showed that erosion rate is lower in sensitized sample when compared to solutionized sample because of their higher hardness in sensitized sample.