Advanced Materials Research Vol. 820

Abstract: A Lead sulfide (PbS) film synthesized by ultrasonic wave assisted chemical bath deposition (CBD) method. The as-deposited films were characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM) measurements. The photoelectrochemical (PEC) cell, with PbS/ITO/glass as a photo cathode and Na₂SO₄ (0.10 M) solution as an electrolyte, was constructed and investigated for PEC properties. The film shows a p-type conduction mechanism.

Abstract: A PbS/CdS based photovoltaic cell was designed and characterized. The as-designed photovoltaic cell has a structure of Al/PbS/CdS/ITO/Glass. The CdS films were prepared by magnetron sputtering. The PbS films were synthesized by chemical bath deposition (CBD) method. The CdS and PbS films were characterized by X-ray diffraction (XRD) and photoelectrochemical (PEC) properties.

Abstract: Hierarchical eight-arm, star-shaped lead sulfide (PbS) crystals have been successfully synthesized by a simple hydrothermal method. When pyridine was used as solvent, candy-like PbS crystal was obtained. The samples were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM) and Fourier transform-infrared (FT-IR) measurements.

Abstract: This paper describes the influence of heat treatment process on the microstructure and properties of a new martensitic stainless steel, which contains 0.7% carbon, 17% chromium and 1% molybdenum and can be used as kitchen knives and scissors. The microstructure and properties of the tested alloys after quenching at 980 - 1100 °C and low tempering were investigated by means of optical microscope (OM), scanning electron microscope (SEM), Rockwell hardness tester and impact tester. The results show that the microstructure consists of acicular martensite, carbides and a litter retained austenite after quenching and tempering. The carbides are mainly (Fe,Cr)₂₃C₆. The content of retained austenite increases with the increase of the quenching temperature. The solubility of carbon in martensite changes similarly. The martensite gets coarser as the quenching temperature increasing. The maximum value of hardness is 59 HRC, when the quenching temperature is 1060 °C. The impact toughness increases when the quenching temperature increases from 980 °C to 1080 °C and then decreases. The suitable heat treatment process for this alloy is quenching at 1060 °C~1080 °C for 30 min and then tempering at 200°C.

Abstract: The microstructural evolution was investigated during partial remelting of 6061 aluminum bulk alloy prepared by cold-pressing of atomized alloy powders. Meanwhile, the effect of heating temperature on semisolid microstructure was also studied. It was found that after partial remelted, a semisolid microstructure with small and nearly spherical particles can be obtained. The microstructural evolution can be divided into three stages: the rapid coarsening of grains and powders, the structure separation and spheroidization of powders, and the final coarsening behavior of primary particles. For most of the primary particles (larger than 10 μm) in the semisolid state, one particle originates from one original powder in the cold-pressed bulk alloy. Furthermore, proper elevated the heating temperature is beneficial to obtain ideal semisolid microstructure.

Abstract: PTFE/Al reactive material was prepared via a hot pressed sintering process and comparative experiments were conveyed considering heating rate, sintering temperature and heat preservation time. The internal microstructure of the material was investigated using metallurgical microscope and stereomicroscope. From the investigation the influence of process parameters of hot pressed sintering on the properties of the material were deduced, and the analysis was verified by testing the impact initiation property with drop hammer method. The density of the material was measured according to the Archimedean principle. and the results showed that the best operating conditions of these three factors are 80°C/h, 365°C, and 0.5h, This new method has a higher effectively (short process time) and need lower operation conditions (low sintering temperature and pressure) comparing with the traditional cold sintering process.

Abstract: By numerical and experimental methods, heat alternating magnetic treatment of diamond agglomerations were researched, the microstructure and mechanical properties before and after treatment were also analysed comparatively. The numerical analysis shows: the alternating magnetic field stress is bound to make solid-state microstructure change, this intensified magnetic shock can broke dendrites and tangles organization within the organization and enables organization uniform, dense. The experiments indicate: After heat alternating magnetic treatment, the HRB hardness of test pieces matrix is improved 4.34, impact toughness enhanced more than 25%, matrix organization became uniformity and density. Results revealed that alternating magnetic treatment can be an effective method for improving the performance of the diamond agglomeration.

Abstract: In order to improve the high temperature oxidation resistance, 75 Si-Fe and the silver paint were selected as cast-penetrated agent using the cast-infiltration method to form an aluminum silicon composite layer on the heat resistant steel grate surface. The microstructure and hardness properties of cast-infiltration layer were studied by optical microscope (OM), scanning electron microscope (SEM) with electron dispersive spectrum (EDS), and micro hardness test. The results show that the cast-infiltration layer is composed of ferrite and irregular shape of carbide particles. Most of the carbides are (Fe,Cr)₃C and a small amount (Fe,Cr)₇C₃ also observed in composite layer. The highest micro hardness of fine carbide particles reaches 1253 HV. The optimized silicon content is 50wt%, and the thickness of infiltration layer reaches 0.6mm.

Abstract: Application of anti-counterfeiting technology in the label has been widespread. This paper has studied the security label based on reflected light interference color, tells the story of its structure and preparation method, and application of glass beads in the label are detailed.