Yttria-stabilized zirconia (YSZ) is well-known as a material with perfect mechanical, thermal, and electrical properties. It is used for manufacturing various high-temperature components for aerospace and energy generation, as well as wear- and corrosion-resistant devices in medicine. This work investigated the effect of a Y2O3 addition to ZrO2 on the microstructure and mechanical properties of YSZ ceramics produced by one sintering schedule. ZrO2 ceramics doped with 3, 4, 5, 6, 7, and 8 mol% Y2O3 (designated 3YSZ through to 8YSZ) were prepared by using conventional sintering at 1550 °C for 2 h in argon. The effect of yttria content was analyzed with respect to grain size, morphology of the microstructural features, phase composition, parameters of fracture surface, and flexural strength. The 7YSZ ceramics sintered at 1550 °C for 2 h showed the highest level of flexural strength due to the formation of the fine-grained microstructure containing mainly the monoclinic and tetragonal zirconia phases. The fracture micromechanism in the studied YSZ ceramics is discussed.

The effect of deformation temperature on microstructure and mechanical properties was investigated for thermomechanically processed NbTi-microalloyed steel with ferrite-pearlite microstructure. With a decrease in the finish deformation temperature at 1348 K to 1098 K (1075 °C to 825 °C) temperature range, the ambient temperature yield stress did not vary significantly, work hardening rate decreased, ultimate tensile strength decreased, and elongation to failure increased. These variations in mechanical properties were correlated to the variations in microstructural parameters (such as ferrite grain size, solid solution concentrations, precipitate number density and dislocation density). Calculations based on the measured microstructural parameters suggested the grain refinement, solid solution strengthening, precipitation strengthening, and work hardening contributed up to 32 pct, up to 48 pct, up to 25 pct, and less than 3 pct to the yield stress, respectively. With a decrease in the finish deformation temperature, both the grain size strengthening and solid solution strengthening increased, the precipitation strengthening decreased, and the work hardening contribution did not vary significantly. The effect of deformation temperature on microstructure and mechanical properties was investigated for thermomechanically processed NbTi-microalloyed steel with ferrite-pearlite microstructure. With a decrease in the finish deformation temperature at 1348 K to 1098 K (1075°C to 825°C) temperature range, the ambient temperature yield stress did not vary significantly, work hardening rate decreased, ultimate tensile strength decreased, and elongation to failure increased. These variations in mechanical properties were correlated to the variations in microstructural parameters (such as ferrite grain size, solid solution concentrations, precipitate number density and dislocation density). Calculations based on the measured microstructural parameters suggested the grain refinement, solid solution strengthening, precipitation strengthening, and work hardening contributed up to 32 pct, up to 48 pct, up to 25 pct, and less than 3 pct to the yield stress, respectively. With a decrease in the finish deformation temperature, both the grain size strengthening and solid solution strengthening increased, the precipitation strengthening decreased, and the work hardening contribution did not vary significantly.

Nickel-Copper (Ni-Cu) alloys exhibit simultaneously high strength and toughness, excellent corrosion resistance, and may show good wear resistance. Therefore, they are widely used in the chemical, oil, and marine industries for manufacturing of various components of equipment, such as: drill collars, pumps, valves, impellers, fixtures, pipes, and, particularly, propeller shafts of marine vessels. Processing technology includes bar forging, plate and tube rolling, wire drawing followed by heat treatment (for certain alloy compositions). Growing demand for properties improvement at a reduced cost initiate developments of new alloy chemistries and processing technologies, which require a revision of the microstructure-properties relationship. This work is dedicate to analysis of publicly available data for the microstructure, mechanical properties and strengthening mechanisms in Ni-Cu alloys. The effects of composition (Ti, Al, Mn, Cr, Mo, Co contents) and heat treatment on grain refinement, solid solution, precipitation strengthening, and work hardening are discussed.

In steels the dependence of ambient temperature microstructure and mechanical properties on solidification rate is not well reported. In this work we investigate the microstructure and hardness evolution for a low C low Mn NbTi-microalloyed steel solidified in the cooling rate range of 1–50 Cs−1. The maximum strength was obtained at the intermediate solidification rate of 30 Cs−1. This result has been correlated to the microstructure variation with solidification rate.

Currently, ceramics are widely used in various industry branches, especially in energy, chemistry, and aerospace, as well as in medicine. Yttria-stabilized zirconia (YSZ) having unique electrical, thermal, and mechanical properties is one of the most popular ceramics for such applications. In this study, the influence of sintering temperature and yttria percentage on the microstructure and mechanical behavior of YSZ ceramics have been investigated. Corresponding mixtures of ZrO2 powder doped with 3 and 6 mol% Y2O3 powders (hereinafter: 3YSZ and 6YSZ) were prepared, and a series of ceramic specimens were sintered in argon at 1450 °C, 1500 °C, and 1550 °C for 2 h. Changes in the morphology and size of microstructural components as well as their distribution were analyzed with respect to the sintering mode, phase composition, flexural strength, and fracture surface morphology. The 3YSZ and 6YSZ ceramics sintered for 2 h at 1550 °C and 1450 °C, respectively, exhibited the highest levels of strength due to the presence of agglomerates of fine tetragonal zirconia phase particles with high bond strength, as well as larger grains of the monoclinic zirconia phase. The dominant fracture micromechanisms in both the 3YSZ and 6YSZ ceramics related to their high strength are discussed.