Face-centered cubic (FCC) high-entropy alloys (HEAs) have attracted considerable attention due to their excellent mechanical properties; however, an insufficient yield strength (YS) limits widespread engineering applications. To improve the of FCC HEAs, present work aims develop fine-grained Nb-containing CoCrNi-based HEAs with precipitates. In work, a single-phase CoCrNi1.5Nb0.2 HEA was proces...

Yttria-doped zirconia powders" with an extremely small crystallite size (8 nm) and a narrow size distribution have been prepared by gel precipitation methods. Precipitation of an alkoxide solution in water ("alkoxide" synthesis) results in weaker agglomerates when compared with a precipitation of a metal chloride solution in ammonia ("chloride" synthesis). Both types of agglomerate are fracture...

In this work, the microstructural evolutions and mechanical properties of an as-cast Mg-10Gd-4Y-1.5Zn-0.5Zr (wt %) alloy during successive multi-pass equal channel angular pressing (ECAP) were systematically investigated by X-ray diffractometer, scanning electron microscopy, transmission electron microscopy, and compression test. The obtained results show that the microstructure of as-cast allo...

Dendritic microstructures are frequently observed in as-solidified refractory high-entropy alloys (RHEAs), and their homogenization typically requires a long-term heat treatment at extremely high temperatures. High-pressure torsion (HPT) has been shown to be capable of mixing immiscible systems room temperature, therefore represents promising technique for homogenizing dendritic RHEAs. In this ...

copper–silver bimetallic strips were produced by cold roll welding process and were treated by diffusion annealing in the temperature range 250–800 ?c. the interface bonding strength was determined by bending and peeling tests, resistance, conductivity and micro hardness profiles were determined and microstructure in the interface region was observed by optical microscope. electrical resistance...

Two solution-based methods, metallo-organic decomposition and sol–gel processes, were used to study the effects of precursor solution type on the microstructure evolution and texture development of oriented PZT films. Microstructure development and perovskite content are strongly dependent on the heating rate. Fast heating rate forms a dense fine-grained microstructure with (111) orientation. I...

structural steels with very high strength levels are often referred to as ultrahigh-strength steels (uhss). the usage of uhss has been extensively studied in aerospace industries and offshore platforms. in this study, medium carbon low alloy steel (ams6305) was thermomechanicaly treated to obtain an ultra-high strength bainitic steel for aircraft engine compressor disk. a novel themomechanical ...