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This grade containing more than 5000 ppm of nitrogen was produced commercially through EAF-AOD-LRF-CC-Steckel mill route and its microstructure and mechanical properties were studied.
Microstructure and mechanical properties of hot rolled plates: Fig 3 shows the microstructure of as hot rolled plates of 50mm and 7mmt thicknesses and Fig.4 exhibits EBSD micrographs of 20mm and 7mm plates.
Mechanical properties and impact strength of as hot rolled plates are given in table-2 and table 3.
Table-2 Mechanical properties of hot rolled plates Thickness (mm) condition YS (MPa) UTS (MPa) EL (%) Impact energy at -40°C (J) Hardness (HV) 50 HR 550 830 52 271 320 20 HR 630 933 50 265 320 15 HR 790 960 45 273 325 7 HR 1032 1098 32 - 441 6 HR 1066 1157 26 - 441 Microstructure of the reheated sample: One sample was quenched after soaking at 11500C for 5 minutes and microstructure of the sample is given in Fig.5 Grain size of the sample is around 45µm.
Conclusion: 1) 18Cr18Mn0.5N high nitrogen stainless steel is successfully produced in industrial scale through EAF-AOD-LRF-CC route and excellent combination of mechanical properties is achieved in hot rolled plates. 2) Dynamic recrystallization has been observed in this high nitrogen steel in the temperature range 8000C to 11000C at strain rate of 5/S as well as 25/S when initial grain sizes is small.

After the initiation, propagation directions of short cracks are very irregular, and they are affected by the grain boundaries acting as barriers.
The propagation behavior of these so-called fine-structural short fatigue cracks is strongly affected by microstructure properties, such as the grain sizes, the grain orientations and the disorientation of grain boundaries [2], and cannot be described using linear-elastic fracture mechanics.
The specimens, prior to SEM examination in a Zeiss DSM 960 microscope, were prepared by a standard metallographic technique of mechanical grinding and polishing.
Obviously, the above difference will considerably affect the cyclic fatigue of the steel [4].
and packets for which a Schmid factor is maximal.

Study on Mechanical Property of Reinforced Concrete (RC) Beams under Sea Water Xikang Yan 1,2,a, Xiangshang Chen1,2,b and Pei Chen 1,2 1 School of Engineering,Hebei University of Technology,China 2 Civil Engineering Technology Research Center of Hebei,China a tjsyxk@126.com, bcxs0928@sina.com Keywords: reinforced concrete, beam, sea water corrosion, bearing capacity Abstract.
In this experimental result, the law for the change of mechanical performance of RC beams with different mix proportions under different dry-wet cycle conditions was investigated through artificially imitated sea water corrosion on the in-site casting RC beams especially on the concrete structure in the wave splash area.
According to relevant research result, it is possible to simulate the real eroding situation affected by natural environment with the aid of seawater spraying test.
Corroded Expansion Force of Reinforced Concrete Members and Its Influence Factors.

Introduction Science and technology development causes the need for ceramic materials with thermal and chemical resistance, high thermal conductivity, good dielectric and mechanical properties [1,2].
Fig. 3 Particle image with different magnificient (scanning electron microscope) а – experiment 5, b – experiment 9 Small yield of aluminum nitride nanopowder in experiments 1-8 (table. 1) due to two factors.
Further experiments with a higher concentration of melamine in the initial mixture were not carried out due to the fact that soot was deposited on the surface of nitride particles, which significantly reduces the electrical insulating properties of the material.
It is determined that the flow rate of the сentral and the composition of the sheath gases, as well as the point of powder injection into the plasma do not affect the AlN output.
Thermal Plasma Spheroidization of High-Nitrogen Stainless Steel Powder Alloys Synthesized by Mechanical Alloying // Metals and Materials International. 2018.

Introduction The phenomenon of crystallization following after pouring molten metal into the mould, determines the shape of the primary casting (ingot) structure, which significantly affects on its usable properties.
Due to the small width of chilled crystals zone, the usable properties of casting (ingot) depend mainly on the width and length of the columnar crystals, the size of equiaxed crystals and content of theirs zone on section of ingot.
According to presented data in papers [3, 4], this type of structure gives low mechanical properties of castings and mainly is unfavourable for the plastic forming of continuous and semi-continuous ingots, because causing forces extrusion rate reduction and during the ingot rolling delamination of external layers can occur.
This structure can be eliminated by controlling the heat removal rate from the casting (ingot), realizing inoculation [3÷10], which consists in the introduction of additives to liquid metal and/or influence of external factors for example infra- and ultrasonic vibrations or electromagnetic field [4, 10÷14].
In case of this inoculation with use of external factor in form of electromagnetic stirring, which creates forced movement of liquid metal in mould in time of its solidification, the refinement of primary structure mainly results from thermal and mechanical erosion of crystallization front.

Numerical Analysis for Galloping of Iced Quad Bundle Conductors Junyan Cai1,2,a, Xijun Liu1,2,b and Suxia Zhang1,2,c 1School of Mechanical Engineering, Tianjin University, Tianjin 300072, China; 2Tianjin Key Laboratory of Nonlinear Dynamics and Chaos Control, Tianjin 300072, China acaijunyan1987@126.com, blxijun@tju.edu.cn, czhangsux@tju.edu.cn Keywords: Bundle conductors, Galloping, Spacers, Anti-galloping Abstract.
Simultaneously, the relation curve between elastic property of spacers and conductor galloping is obtained.
In companion papers, the influence of various factors such as non-linear aerodynamic loads and non-uniform ice geometry on conductor galloping was taken into account by Q.
The galloping of iced quad bundle conductors often causes line break and the damage of conductor components, which seriously affecting the normal operation of transmission lines.

The quality requirements of thread type of mechanical parts mainly include dimension consistency, internal and external defects and mechanical properties, which have corresponding mature inspection methods.
Among dimension measurements, the key geometry element, screw thread, will affect the whole performance and long term availability of product.
Otherwise, it will lead to extra shading error. 3) The related position between axis of screw thread and optical axis becomes the main factor when applying backlight vision measurement and traditional image measurement.
Therefore, it is important to guarantee this position precision through mechanical fixture or other methods.
Shading effect, however, doesn’t affect the measurement of last three ones.

It is generally believed that the mechanical properties, electrical insulation properties, heat resistance properties, chemical resistance properties, and resistance to acids, alkalis, and many chemicals of composite materials are the most important components of composite materials.
Epoxy resin has excellent mechanical properties and heat resistance It is one of the bases for manufacturing high-performance composite materials and chemical resistance [2].
These excellent properties of epoxy resin, such as mechanical properties, heat resistance and chemical resistance, are one of the important substrates for manufacturing high performance composite materials [3].
Epoxy resin has the following major properties: (1) Low viscosity and good processability.
When the reaction temperature reaches 110 °C, the change in temperature no longer affects the epoxy value.

This paper discusses how the orifice layouts and the orifice diameter affect the self-excited vibration of the aerostatic guideway, or two-dimension x-y stage as a whole.
Because of its high accuracy and low friction properties, it has broad applications in the field of large-scale integration (LSI) manufacturing, micro mechanical processing, anatomy of fine structure of organism, two-dimensional precision measuring and so on.
Fig. 1 Structure of aerostatic x-y stage Fig. 2 Factors of causing the self-excited vibration Many factors can cause the self-excited vibration of aerostatic stage, such as supply pressure, diameter of orifice, diameter and depth of air pocket, thickness of gas film[7], etc, among which diameter of orifice and the structure of orifice (with or without air-pocket) are the main factors, as shown in Figure 2.
Studies on the aerostatic guiding system—influence of several design factors on occurrence of self-excited vibration.

Takahara et al. [13] investigated the allowance of deviation and gap for butt welding of 3mm plates of AA5083-O alloy and found that a gap up to 2mm did not affect the tensile properties of their welds.
The chemical composition and mechanical properties of the parent plate are given in Table 1.
Table 1: Chemical composition (in wt. %) and mechanical properties of AA5182-H111 (T500).
Fatigue properties of friction stir welds in Al 5083 alloy.
The influence of zigzag-curve defect on the fatigue properties of friction stir welds in 7075-T6 Al alloy.