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Item A Review on Mechanical and Microstructure Properties of Reinforced Concrete Exposed to High Temperatures(Springer, 2021) Goudar, S.K.; Santhosh, S.K.; Das, B.B.This paper presents the recent research progress on the response of concrete exposed to fire or high temperatures. The main highlight of this review paper is a compilation of previously reported data regarding the variations in mechanical properties and microstructure properties of concrete when exposed to high temperatures. The concrete structures get deteriorated at the macro- and microscopic levels due to high-temperature exposure. The macro-level damages can be measured with degradation in mechanical properties such as the reduction in compressive strength, weight loss, changes in elastic properties, reduction of bond strength in reinforced concrete, etc. The macro-cracks on the surface of concrete causes spalling which can be observed after exposing the concrete samples to more than 300 ℃. The compressive strength of the concrete reduces slightly till 400 ℃, and when the temperature increased to 600 ℃, there was an exponential reduction in the compressive strength of concrete. Another important parameter is bond strength degradation, which plays a crucial role in durability issues. To understand the deterioration phenomenon and changes in mechanical properties, the changes at the level of the microstructure of concrete need to be understood. Dehydration of products causes deterioration of mechanical properties and weight loss of concrete when exposed to high temperatures. At different temperatures, the microstructure changes and the response of hydration products such as calcium hydroxide (CH), CSH gel, unhydrated cement and capillary water reported by previous researchers are compiled and discussed. © 2021, Springer Nature Singapore Pte Ltd.Item Influence of Impact Angle and Temperature on Solid Particle Erosion Behavior of Titanium-31(Springer Nature, 2024) Behera, N.; Chandramouli, T.V.; Aprameya, C.R.; Ramesh, M.R.The present work shows the effects of impact angles and temperatures on volumetric erosion loss of titanium-31 alloy. An erosion tester was used to perform the erosion tests with temperatures (200, 400, 600, and 800 °C) and impact angles (30°, 60°, and 90°). The alumina particles (Al2O3) are used as an erodent particle with an average particle size of 50 μm. The microhardness, porosity, and surface roughness of titanium-31 alloy are evalu-ated. SEM/EDS and XRD were used to analyze tita-nium-31 alloy eroded samples. The weight loss method and 3D profilometer determined the volumetric erosion loss. The microhardness of titanium-31 alloy is found to be 337 ± 15HV0.3. The Volumetric erosion loss of tita-nium-31 alloy increased with increasing temperatures from 200 to 800 °C, whereas decreased with increasing impact angle from 30° to 90° for all temperatures. The volumetric erosion loss is higher at a 30° impact angle and lower at a 90° impact angle for all temperatures. As a result, titanium-31 alloy shows the ductile erosion mode for all temperatures. The volumetric erosion loss at 30° impact angles is due to micro-cutting and plough-ing, whereas deep crater, groove, and raised lips are for 90° impact angles. The results of volumetric erosion loss obtained by the weight loss method exhibit a good cor-relation with a 3D optical profilometer. © The Author(s), under exclusive license to Springer Nature Switzerland AG 2024.