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Road markings regulate and direct traffic by conveying specific information. It is of great significance to develop new road marking materials and improve the visibility of marking materials for improving traffic efficiency and ensuring traffic safety. This paper summarized the development status of various reflective road markings at home and abroad. In addition, the energy storage luminescent fluorescent/phosphor marking lines in road marking was emphatically generalized to evaluate the advantages and disadvantages of different improvement methods. Overall, strontium aluminate doped with Eu2+ co-doped with Dy3+ (SrAl2O4:Eu2+, Dy3+) phosphors and self-luminous pavement for energy storage had great prospects in improving road safety and reducing energy consumption.

In this paper, aiming at the heat resistance and thermal deformation process of titanium matrix composites 0 vol.%, 2.5.vol.%, 5.vol.%. Thermal simulation experiment of titanium matrix composites with different (TiB+TiC) strengthening phase content. The measurement accuracy of material displacement is 0.01 mm. The compression is 70%, and the strain rate is 0.1 mm/s and 0.01 mm/s respectively. Compression tests at different strain rates and temperatures were carried out. The experimental results show that when the (TiB+TiC) 5vol% titanium composite is deformed at 0.01mm/s low strain rate, the peak stresses corresponding to 25°C, 250°C,350 °C and 500°C are increased to 1096MPa, 835MPa, 646MPa and 416MPa respectively. Under the condition of high strain rate of 0.1mm/s, the peak stresses corresponding to 25 °C, 250 °C, 350 °C and 500 °C are increased to 1230 MPa, 896 MPa, 723 MPa and 471 MPa respectively. The deformation law of stress rheological curve is roughly the same, and the high temperature zone has good plastic deformation ability. The titanium matrix composite has high compression rheological mechanical properties and good high-temperature plastic deformation ability. It is the preferred material component for the preparation of titanium matrix composite and powder forging.

This paper mainly studies the composition of strengthening phase, characteristic precipitation temperature and composition range of strengthening phase in Ti-Al-Mo-Zr-Si medical titanium alloy, and the influence of element changes on the content and microstructure of strengthening phase. Promote the formulation of thermodynamic process of titanium alloy powder metallurgy, as well as the formulation of alloy hot working and solid solution aging process. In this paper, Panda thermodynamic software is used to calculate the multicomponent alloy thermodynamics and multicomponent phase diagram of titanium alloy materials. The effects of Al, Mo, Zr, Si and other elements on the precipitation of strengthening phase and the phase transformation content of solidification structure were obtained. It is found that the content of Mo is more than 2 wt.% β phase transition precipitation angle. Meanwhile, in order to avoid the excess of precipitates such as Mo5Si3 and M3Si, the content of Mo should be less than 4.6 wt.%. The content of Zr can be maintained at about 1.5 wt.%. If the aging precipitation of the material is considered, it can be controlled to be less than 2 wt.%. The content of this paper is the basis and improvement of titanium powder metallurgy technology and rapid prototyping technology.

Pores and weak bonding are the inherently drawbacks for thermally sprayed coating. Laser beam is an attractive approach to remelt thermal spray coating for obtaining fully dense coating with metallurgical bonding with substrate. However, defects of holes or cracks are highly inevitable with unmatching remelting processing parameters. In this work, a thermally sprayed Cr3C2-NiCr cermet coating by high velocity oxygen fuel spraying was post-processed by laser remelting with a series of varying beam energy densities from 37.5 J/mm2 to 225 J/mm2. The defect evolution was investigated by both experimental and numerical simulation methods. Large holes and through-thickness cracks were typical defects observed in the remelt coating by optical microscopy. The experimental results show that remelting-induced defects evolve into three stages with laser energy density. The effect of energy density on remelt structure was further verified with the temperature field by numerical simulation with ABAQUS code. The stress field interpreted the crack formation at periodical formation sites. The results on the defect evolution shed light on obtaining functional coatings for industrial applications.

Investigation on the casting, hot-rolling and heat treatment process of a high boron-bearing advanced high strength steel was conducted. The scanning electron microscopy (SEM), electron-probe micro-analyzer (EPMA), electron backscattered diffraction (EBSD) and X-ray diffraction (XRD) were employed to analyze the evolution of microstructure which includes the phase constitution and boride morphology during hot processing. Through the control of as-casted, heat treated microstructure and using interrupted tensile tests, the strengthening mechanism was revealed. Results showed that, the strain-induced ferrite transformation of austenite and grain size were the decisive factors which control the strength and ductility, while the defects and internal stress etc. were the secondary factors.

The demolished concrete lumps (DCLs) have been demonstrated to replacement partial coarse aggregates when casting concrete. However, few studies had focused on the sensitivity of factors affecting mechanical behavior of slender square steel slender columns filled with DCLs and fresh concrete (FC) under axial compression. This research was carried out on the basis of Bo Wu's study. The Orthogonal design method was adopted in this experiment. The experimental studied involved 12 Concrete-Filled Steel Tube (CFST) columns. Each columns diameter was 159mm, the length of specimens was 2000, 2200 and 2400 mm. The Diameter-to-thickness (D/t) ratio was 79, 53 and 40. The replacement ratio of FC by DCLs was 0, 20, 40 and 60%. Test results indicated that the slenderness ratio was the most sensitive factor on the bearing capacity of slender columns under axial compression, followed by D/t ratio, and the DCLs replacement ratio was smallest factor. The ultimate bearing capacity decreased slightly with increasing DCL replacement ratio. The DCLs had slightly affect on the mechanical performances of slender CFST columns. the code CECS 28:2012 was used to calculate the bearing capacity of slender CFST columns filled with DCLs under axial compression.

Due to the deficiencies such as shallow hardened layer and short fatigue life of the ball screws treated by the traditional induction quenching process, a new process has been developed. The new induction quenching process has four-turn induction coil. The power of the this process is 150-160kw, feeding speed 270mm/min and the spraying cooling water distance is 35mm. It has been successfully used on the Cr-Mo steel ball screw with a diameter of 80 mm. The microstructure and hardness distribution of the induction hardened layers were investigated by a metallographic microscope and a micro-hardness apparatus. The fatigue life of the ball screw was measured through a constant stress accelerated fatigue test. The degree of fatigue wear on the raceway of the ball screw was analyzed by a field emission scanning electron microscopy (FE-SEM). The experimental results showed that the microstructure and hardness distribution of the hardened layer of the Cr-Mo steel ball screw could satisfy the design requirements of contact fatigue resistance. The fatigue life was longer than the theoretical service life and there was no obvious fatigue wear on the raceway after the fatigue testing. It shows that the safety and reliability of the Cr-Mo steel ball screw fabricated through the new induction quenching process could be guaranteed in practical application.

A new unsymmetrical diarylethene derivative 1-(1, 5-dimethyl-2-pyrrolecarbonitrile) -2-[2-methyl-5-(4-aminomethyl) phenyl-3-thienyl] perfluorocyclopentene (1o) was designed and constructed successfully. Its optoelectronic properties have been discussed systematically, such as photochromic, kinetics experiments in acetonitrile solution and PMMA.

The mechanical properties, including the compressive strength, flexural strength and adhesion strength of the rapid setting conventional and polymer-modified waterproof mortars are systematically compared in this paper. The polymer modification is demonstrated to increase the flexural strength and adhesion strength of the rapid setting waterproof mortar whereas it reduces its compressive strength.

In order to study the influence of different types of weld defects, such as slag inclusion, porosity, incomplete fusion, incomplete fusion, burn through, crack on the mechanical performance of X65 marine pipe welding joint (Φ323.9 x 16 mm), the test on the mechanical properties of static tensile, fracture toughness CTOD and fatigue life were carried out to achieve the maximal defect tolerance size allowed in this paper. Research shows that the existence of crack defects would significantly reduce the fracture strength and the fatigue life of welded joint, the application of the maximal defect tolerance size allowed based on crack defects assessment can provide referential basis for the safe and stable operation of marine pipelines.