WC-Co coatings were produced on SS 410 plates and subjected to heat treatment at different temperatures (from 300 to 900 °C). The microstructural studies and structural analysis of the coatings before and after heat treatment were carried out by electron microscopy and X-ray diffraction analysis. From the Vickers indentation method, hardness values were measured, and higher microhardness was observed for the coatings after heat treatment. The sample that was heat-treated at 750 °C exhibited the highest hardness. From the sliding wear test results, the wear resistance of the coatings was observed as increased after the heat treatment. However, it was found that the heat-treated coatings at 600 °C exhibited higher wear resistance. Cracking and fracture were the dominant wear mechanisms observed for the heat-treated coatings, along with coating delamination and oxidation.
The WC-12Co coatings were deposited on SS 410 substrates using a high-velocity oxygen fuel (HVOF) process and the coatings were heat-treated at 750°C for 1 h in argon environment. Further, the coatings were subjected to cryogenic treatment for 1, 2, 8 and 24 h, and its influence on the reciprocating sliding wear and corrosion characteristics was studied. The structural changes in the coatings after post-treatment were assessed by X-ray diffraction analysis and Raman spectroscopy. Microhardness was improved for cryogenically treated coatings due to the α-Co transformation into ε-Co. Cryogenic treatment duration was not having a significant effect on the microhardness values. However, the specific wear rate was influenced by the cryogenic treatment duration. Also, corrosion resistance was increased with the increased cryogenic treatment duration. The protective layers consisting of WO 3 and Co 3 O 4 phases formed during the cryogenic treatment are attributed to the improved corrosion resistance of the coatings.
In the present study, hybrid composites of AZ91E reinforced with granite powder and fly ash powder were fabricated by stir casting route. The reinforcing material was added in different weight fractions (2.5 and 5 % each). The densities of the composites were measured between 1.74−1.8 g/cm3. The role of different weight percentages of reinforcements on the machining behavior was investigated. Increased microhardness was measured for the composites due to the presence of the reinforcing material. Higher cutting forces were measured for the composites containing higher fraction of reinforcements. With the increased cutting speed (420 to 715 rpm) the cutting forces were observed as decreased and with the increased depth of cut (0.2 and 0.4 mm), higher cutting forces were recorded. At higher fraction of reinforcements, discontinuous chips were observed for the composites. The results demonstrate the significant role of granite powder and the fly ash powder on enhancing the mechanical properties (up to 66% compared with the base alloy) but also on increasing the difficulty level in machining.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.