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The Mn2O3@ZnMn2O4/C hollow microspheres were synthesized by room-temperature stirring and then annealing under air atmosphere. Benefiting from the unique structure, its application in AZIBs as cathode exhibits excellent electrochemical performance.

CrFeNiTix (x = 0.2, 0.3, 0.4, 0.5, and 0.6 molar ratio) compositionally complex alloys were fabricated by vacuum arc melting to investigate the microstructure, hardness, and compressive properties. The results revealed that CrFeNiTix alloys consisted of the principal face-centered cubic (FCC) phase and body-centered cubic (BCC) solid solution, with an amount of (Ni, Ti)-rich hexagonal close-packed phase. CrFeNiTix alloys exhibited the typical dendrite. Ti0.2 and Ti0.3 alloys were composed of FCC and BCC solid solutions in the dendrite, as well as e (Ni3Ti) and R (Ni2.67Ti1.33) phases in the inter-dendrite, simultaneously. For Ti0.4, Ti0.5, and Ti0.6 alloys, (Fe, Cr)-rich solid solution separated out and e phase transformed into R phase gradually. Meanwhile, TEM analysis indicated that Ti0.4 alloy matrix consisted of the principal FCC phase containing (Ni, Ti)-rich intragranular nanoprecipitates. The hardness values of CrFeNiTix alloys were increased with the addition of Ti content and the high compressive strength of CrFeNiTix alloys was maintained, which was attributed to the solid solution strengthening and precipitation hardening.

Based on the interfacial reaction model between Ti and ZrO2 in gravity field, taking account of the effect of electromagnetic field, a comprehensive numerical model for simulation of heat and mass transfer is established to study the interfacial reaction between liquid Ti and ZrO2 in electromagnetic field. With the proposed model, numerical simulations are preformed to investigate the influences of pouring temperature, holding time on the oxygen concentration and reactive layer thickness in metal. The results show that both the oxygen concentration and the thickness of reactive layer in metal increase with increasing the holding time and the pouring temperature. The thickness of reactive layer in electromagnetic field is greater than that in gravity field.

AlN and TiN thin films are widely used in electronic devices and acoustic material and other fields because of its unique merit, the preparation of nitride thin films by using the arc ion plating has not been a systematic and deep study. The article presents our research procedure which the AlN and TiN thin films are deposited on stainless steel substrate by arc ion plating (AIP). The characteristics of thin films, for example microstructure, morphology, composition analysis and hardness, are examined and analyzed. The results showed that: Droplet-like particles appear in the microstructure of nitride thin films, and the grain size of droplet-like particles in AlN thin films is greater than in TiN thin films. The micro-hardness of nitride films preparation in experiment has improved significantly, and establish firmly basic for extending the application field of nitride film.

Al-Cu alloy castings are obtained in the vertical centrifugal field. The effects of solution treatment on the microstructures and mechanical properties of Al-Cu alloy casting were studied by OM, micro hardness tester and room temperature tension and compression test. The results show that, the strength, micro hardness and elongation percentage of Al-Cu alloy casting increase firstly and then decrease as the solution temperature increases, and the mechanical properties reach the maximum values as the solution temperature increases to 530°C. As solution time increasing, the mechanical properties of Al-Cu alloy casting increase firstly and then decrease. When the solution time is up to 6 hours, the mechanical properties reach maximum value.

Titanium alloy castings are made by means of induction melting technology. The relationships thickness of lamellar α+β phase and tensile strength, yield strength, elongation percentage, and Vickers-hardness, as well as the effect of tensile property on the Vickers-hardness are investigated for Ti-6Al-4V alloy castings. The results show that the relationships between thickness of lamellar α+β phase, and tensile strength, yield strength, specific elongation, and Vickers-hardness meet the Hall-Petch equation. And the tensile property increases linearly with Vickers-hardness.

The wettability between pure liquid titanium and calcia-stabilized zirconia was studied in argon atmosphere. The micrographic observations made on cross section perpendicular to the interface using SEM showed that interfacial reaction occurred. However, the contact angles were larger than 90°within experimental duration.

Ti-6Al-4V alloy castings are made by means of induction melting technology. The relationships between grain size and tensile strength, yield strength, elongation percentage, investigated for Ti-6Al-4V alloy castings. The results show that the relationships between grain size, and tensile strength, yield strength, specific elongation, meet the Hall-Petch equation.

In this dissertation, the electric arc spraying coatings on steel structure were sealed over with the organic coatings addition with nano-sized TiO2, SiO2. Some means as light microscope, SEM, energy spectrum and binding force tests were adopted for research the permeability of the sealer. The mechanism for permeable closeness of the sealer was mainly discussed. The results indicated that homogeneous nanofillers can improvement the runnability and permeability of the epikote, stiffen the adhesion between the coatings and the metal substrate. The coating can seal the metal substrate effectively; enhance the protective property of the tectonic systems with electric arc spraying coatings and organic coatings.

Using the method of numerical simulation and the AnyCasting software, the simulation for SDAS of Al-Mg alloy wheels for low pressure casting is studied. The simulation model is established and the effects of preheating temperature, melt pouring temperature and cooling water pipes on SDAS in the low pressure casting process was founded. The results show that, SDAS presents linear variation with the increase of preheating temperature and pouring temperature; opened cooling pipes make SDAS smaller. The practice of simulating casting is verified by experiments, and test results and simulation results were consistent.

Analysis the electricmotorcar aluminum wheels’ hole defect on macroscopic and microscopic, observed that the main defects、concentrated site and the main alloy phase. Combined with the local casting technological parameters, the filling and solidification process of aluminium alloy hub was simulated by using Anycasting software. The results showed that: castings filling smoothly, at the junction of the spoke and the rim and the hub central are easy to produce casting defects. Using the optimized process parameters that is lower pouring temperature, higher pouring height and set the vent to experiment, after comparing the results with the original process known, Shrinkage and porosity defects decreased, but there are still some degree of defects, indicating optimized process parameters have some effect.

Due to developing the strengthening effect of liquid jet peening on the surface modification for metallic materials, in this study, an emulsion jet peening is produced by injecting a high-speed emulsion jet into an emulsion filled tank. The test system and fixed emulsion of cavitation jet was developed. High speed photography technique was used to observe and analysis the structure of emulsion cavitation jet at various upstream pressures . The results indicate that the structure of emulsion cavitation jet in terms of jet impact pressure, intensive degree and uniformity is better than that water jet. The jet structure depends on the jet pressure. The cavitation jet length increases rapidly at the initial stage and then it stabilizes after few milliseconds. The stabilized length of jet increases and the diverges angle decreases with increasing pressures. Specimens made of plan carbon steel (Q235A, China standard) were exposed to emulsion jet peening at the stand-off distances of 20 mm with a constant upstream pressure, 20 MPa for 60 s. The fatigue test shows that the crack initiation life by treatment of emulsion jet peening increases about 12.5% and 20.2% compared to water jet and unpeened specimen respectively.

In this work, the effects of centrifugal radius and mould rotation speed on the tensile strength, yield strength, specific elongation, and microhardness on Al-Cu alloy castings are investigated. The results show that, with increasing the centrifugal radius or mould rotation speed, the mechanical properties increase gradually. With increasing the centrifugal radius, the variation amplitude of mechanical properties of Al-Cu alloys at mould rotation speed 600rpm is greater than that at 300rpm. This is due to the finer microstructure and the strengthened grain boundary and then resulting in the increase of the resistance to dislocation slipping.

By means of induction melting technology, Ti-6Al-4V alloy staging casting was made with the same rotation velocity and centrifugal radius. The effects of casting modulus on the grain size, the thickness of lamellar α+β phase, and the Vickers hardness, as well as the relationships between Vickers hardness, grain size and thickness of lamellar α + β phase were investigated. The results show that the greater the modulus, the larger the grain size and the thickness of lamellar α + β phase, and the less the Vickers hardness. The relationship between Vickers hardness and grain size meets the Hall-Petch equation: Hv=353.45+74.17 d G −1/2 . The relationship between the Vickers hardness and the thickness of lamellar α + β phase is expressed as Hv=2.45 d α + β 2 - 35.96 d α + β + 476.84.