Experimental Study of Strain Waves in Materials with a Microstructure

Transmission of a pulse with a velocity different from the velocity of longitudinal waves is observed in a material with a microstructure. It is demonstrated that, in the presence of an internal structure, the wave properties of a medium acquire some particular features that cannot be described in terms of the classical theory of elasticity.     

Overview of Microstructure and Microtexture Development in Grain-oriented Silicon Steel

This paper outlines the development of the microstructure and microtexture of grain-oriented silicon steel during the industrial production process. In particular the evolution of the Goss orientation was studied in industrial material as well as in single crystal experiments.     

Thermal Stability of the Microstructure and Mechanical Properties of the Ferritic-Martensitic Steel EK-181

Russian Physics Journal - Thermal stability of the microstructure and high-temperature mechanical properties of the low-activate 12% Cr ferritic-martensitic steel EK-181 are studied at temperatures...     

Characterization of Microstructure and Stability of Precipitation in SIMP Steel Irradiated with Energetic Fe Ions

A type of home-made reduced activation martensitic steel, high silicon(SIMP) steel, is homogeneously irradiated with energetic Fe ions to the doses of 0.1, 0.25 and 1 displacement per atom(dpa), respectively, at 300°C and1 dpa, at 400℃. Microstructural changes are investigated in detail by transmission electron microscopy with cross-section technique. Interstitial defects and defect clusters induced by Fe-ion irradiation are observed in all the specimens under different conditions. It is found that with increasing irradiation temperature, size of defect clusters increases while the density drops quickly. The results of element chemical mapping from the STEM images indicate that the Si element enrichment and Ta element depletion occur inside the precipitates in the matrix of SIMP steel irradiated to a dose of 1 dpa at 300℃. Correlations between the microstructure and irradiation conditions are briefly discussed.     

Effect of Magneto-Pulse Processing on the Microstructure and Magnetic Behavior of Amorphous Electrotechnical Steel

The effect of magneto-pulse processing on the microstructure and magnetic behavior of amorphous electrotechnical steel is studied. It is found that the directed ordering of Fe atoms helps to increase specific magnetization of saturation and the coefficient of the squareness of the hysteresis loop, and is related to ordering of the spin system.     

Microstructure and Mechanical Properties of Austenitic Steel EK-164 After Thermomechanical Treatments

Russian Physics Journal - The influence of thermomechanical treatments, including low-temperature and subsequent warm deformation, on the microstructure and mechanical properties of an austenitic...     

在聚合物表面刻写方格子的新方法及理论研究

为了提高制作偶氮苯微结构的实验技术,在偶氮苯聚合物的光致异构和光致取向特性的基础上,利用两激光束的新实验方案,运用比较简便的分步制作的方法,成功的在偶氮苯功能化聚合物薄膜表面“刻写”出二维的正方格子结构。提出了一个新的光异构取向场理论：在两束偏振方向互相垂直的偏振光照射下,偶氮苯聚合物表面光栅的形成是光异构取向场的干涉的结果,并对实验现象进行了解释。用计算机对实验结果进行了模拟,将模拟结果与实验结果进行了比较,结果表明计算机模拟将会更加有利于偶氮苯聚合物微结构的设计和制作。     

Effects of High Magnetic Fields on the Microstructure Formation in a 42CrMo Steel During Solid Phase Transformations

This paper summarizes our recent work on the application of high static magnetic fields to the austenite-to-ferrite transformation and the tempering processes in hot-rolled 42CrMo steel. The thermodynamic and kinetic effects of the high magnetic fields on austenite decomposition and the influences of the high magnetic field on carbide precipitation and the matrix recovery during high- and low-temperature tempering are briefly outlined. Insight into these aspects may provide better understanding of the effects of high magnetic fields on diffusional phase transformations and is of both theoretical significance and technical interest.     

Development and Application of WC-Based Alloys Bonded with Alternative Binder Phase

WC–Co alloys have enjoyed great practical significance owing to their excellent properties during the past decades. Despite the advantages, however, recently there have been concerns about the challenges associated with the use of Co, i.e. price instability (the major incentive for alternative binder development), toxicity and properties degeneration. Thus, the current study applies towards summarize the current knowledge of the impacts of different binders partial or total substitution of the traditional cobalt binder highlighting the influences of metal, intermetallic compound, ceramics (metal oxide) binders on the sintering behavior as well as mechanical properties of WC-based alloys, so as to provide reference for those who would like to enhance the performance of cemented carbides with better reliability advancing them to further wide applications and prepare the alloys in a way that is environment friendly, harmless to human health and low in production cost. It is concluded that the alternative for cobalt in tungsten carbide cemented carbide is economically and technically feasible. Strict control of the chemical composition of the binder coupled with taking into careful account the effects of sintering process and subsequent treatments is of great importance to improve the sintering behavior and tailor mechanical properties of tungsten carbide-based hardmetals.     

A Two-Dimensional Relaxation Study of the Evolving Microstructure in a Mixed Biopolymer Gel

It is shown that two-dimensional (2-D) T ₁–T ₂ relaxation spectra are sensitive to the changing microstructure in a model food system comprising water-in-water gelatin–agarose gelled emulsions. This 2-D relaxation–microstructure relationship suggests that T ₁–T ₂ spectra have the potential of acting as “fingerprint” molecular biomarkers of microstructure in complex water-rich biological systems and this has important future implications for in vivo magnetic resonance imaging studies of food digestion and of the changing structure of cancerous tissue.     

杨/柳絮与其他天然纤维的微观结构比较研究

以春季漫天飘飞的杨絮/柳絮为研究对象,将其与棉花/蚕丝天然纤维的微观结构进行比较研究,分别用体视显微镜、扫描电镜观测其形貌;用溴化钾压片法及全反射(ATR)测定FTIR光谱。分析研究其形貌及微观结构,实验结果表明：杨絮/柳絮与棉花/蚕丝天然纤维形貌有显著差异-棉花纤维较粗、且具有优良的拉伸性能,而杨絮、柳絮纤维则较短,拉伸性能比较差;FTIR光谱比较分析,发现棉花与杨絮、柳絮的主要化学结构都是纤维素,但是棉花纤维中氢键结合的羟基(-OH)伸缩振动吸收峰吸收强度明显大于杨絮,这也是导致棉花纤维长、纤维拉伸性能优于杨絮、柳絮的因素之一;蚕丝纤维与棉花、杨絮柳絮这些植物纤维不同,它的主要结构为酰胺结构。它们微观结构的差异决定了这些纤维不同的性能和用途。     

Microstructure and properties of a copper electrocontact material with a nanodispersed titanium dioxide additive

The influence of TiO₂ nanopowder additive on the microstructure, physicomechanical properties, and performance characteristics of a copper-based composite is studied. The properties of the composites are compared with those of pure copper compacts. The microstructure and state of the composite’s working surface after performance tests are examined. It is shown that, when the amount of TiO₂ grows, the hardness of the material rises and the arc quenching effect is enhanced.     

钢大气腐蚀锈层的红外、拉曼光谱研究

运用红外光谱、拉曼光谱分析的方法,对碳钢A₃和低合金钢10CrMoAl经青岛大气腐蚀的锈层样品,进行了比较测试,综合分析得出锈层中主要组成物相为α-Fe₂O₃,γ-FeOOH, α-FeOOH, δ-FeOOH,Fe₃O₄,以及各组成物相相对含量随腐蚀时间的变化情况。     

苯酚苯胺共聚物在304不锈钢电极表面的电化学合成及成膜微观结构分析

苯酚和苯胺在304不锈钢阳极表面实现了电化学共聚,反应在中性水溶液中进行,电解质为硫酸钠. 比较不同苯酚苯胺浓度下共聚成膜耐点蚀能力,当苯酚为0.09 mol/L和苯胺为0.01 mol/L时最佳.红外光谱分析证实苯胺结构出现在苯酚苯胺的共聚物中,且共聚物膜比聚苯酚膜含有更多支链. 利用苯酚苯胺共聚物膜在四氢呋喃中的部分溶解性,使用扫描电子显微镜分析四氢呋喃清洗前后的成膜,观察到网状聚苯胺结构. 将共聚物膜与聚苯酚膜微观结构进行推测和比较,解释在电聚合反应中适量加入苯胺能提升成膜防腐能力原因.     

硬玉熔体和玻璃的结构研究

硬玉(NaAlSi₂O₆)及其在极端条件下的行为在地质学和宝石学中有极高的研究价值。考虑到现有单一检测条件的局限,本文综合了多种实验检测手段和理论计算方法对硬玉晶体及其熔体和玻璃的结构以及铝配位数进行了研究。对硬玉晶体热熔过程进行了高温原位拉曼光谱测定,结合第一性原理理论计算方法,得到了硬玉结构和铝配位数的变化及其相应的谱学特征。结合量子化学从头计算对熔体结构进行解析。研究表明：硬玉晶体结构单一且铝全部为六配位,1 293 K时大量六配位铝转变为四配位,熔体中四配位铝占主导,其中硅(铝)氧四面体以多元环连接成架状结构。熔体冷却过程中伴随着五配位铝的生成,并呈现分相趋势。     

黄冶窑白瓷的物相和微观结构研究

以黄冶窑四个时期的白瓷样品作为研究对象,利用X射线衍射仪（XRD）和扫描电子显微镜（SEM）对样品进行分析,结果表明:黄冶窑白瓷胎的物相基本相同,主要是莫来石、α石英和方石英、未熔石英和少量的粘土相;黄冶窑白瓷釉中有气泡存在,釉中气泡为圆形,釉中存在微米级的针状或柱状钙长石晶体,釉存在分相结构,且分相结构与析晶相伴而生;黄冶窑白瓷胎中有气孔、未熔的石英颗粒、较大的Ti颗粒、莫来石晶体和石英晶体。The white porcelain samples of the four periods of Huangye kiln were studied in this paper, and the samples were analyzed by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results show that the material phase is basically the same of the white porcelain bodies from Huangye kiln, and mainly mullite, alpha quartz and cristobalite, unmelted quartz and a small amount of clay phase; There are some round bubbles in HuangYe kiln white porcelain, glazes, so are some feldspathic crystals with micro-level needles or columnar. It is evident to observe phase separation structure, which is accompanied by the birth. Apart from some pores, unfused quartz particles, larger Ti particles, mullite crystals and quartz crystals can also be found in the embryo of Huangye kiln white porcelain.     

纯ZrO_2纳米粒子结构的拉曼光谱研究

本文对粒径在５８～１０ｎｍ范围内不同粒度的纯ＺｒＯ＿２粒子进行了拉曼散射光谱研究。结果表明，粒子的点阵结构受表面效应的影响，粒径的减小，粒子表面层结构严重畸变，但仍是有序的结构。同时，表面效应将进一步引起ＺｒＯ＿２粒子点阵结构变化，在室温下，使单斜相的粒子自发地转变为四方相结构。ＺｒＯ＿２粒子由单斜相向四方相转变的临界直径为１５ｎｍ。