Advanced Materials Research Vols. 189-193

Abstract: This paper presents a proposed system based on LabVIEW for data acquisition and monitoring of manufacturing process in machine tools with CNC. It was applied to evaluate work piece dimension and failure analysis in real time. The proposed system was developed and tested initially in a CNC milling machine with open architecture. Furthermore, it can be extended to other machines and processes, lines or cells of mass production as well. And it was applied in some factories and workshops now.

Abstract: In this paper, effect of FBG coating in curing monitoring of composites was studied. In the experiment, three kinds of sensors were embedded in the composites. Excursion of the wavelength and temperature was tested in the whole curing process. 3-point bending test of composites which FBG was embedded in was done. Results showed that FBG could be exactly reflecting the relationship of stress and strain in bending state of composites. After cured, composites were heat up to 180°C for 1 hour. Sectional appearance of different optic fibers in room temperature and high temperature was got by optical microscope.

Abstract: The C102B reciprocating piston compressor is an important equipment widely used in methanol production. Because of the complexity of exact dynamics analysis, the traditional and common way to find the reason of fracture is only based on metallographic structure analysis of crosshead material. In this paper, after metallographic structure analysis of crosshead material of the C102B compressor, the maximum loads on it are also calculated and two dangerous crosshead positions with maximum load are determined. Finally, stress analysis of the crosshead in two dangerous positions is implemented by FEM technology. Based on the above study, the reasons of crosshead fracture of the C102B compressor are found. The results has an inportant significance for judging the resaon of crosshead failure.

Abstract: Mg-Al-Zn alloys of 2% Nd and without Nd, which produced by spray deposited method, were heat treated at different solid-solution and the same aging treatment. The microstructure and hardness were analyzed by SEM , XRD and HV tester. The experimental results showed that Nd can make the spray deposited magnesium matrix grains tiny evenly, formed the second phase particle Al3Nd, and increased the hardness value. With the rise of solution temperature, the hardness of without Nd magnesium alloy show that rise firstly and then fall rapidly, but the 2%Nd magnesium alloy hardness increase all the time with the rising of solution temperature, and the hardness value increase sharply to the highest 181Hv after 448°C/3h+205°C/24h.

Abstract: Steel structures are seriously affected by sandstorm in the central and western regions of Inner Mongolia, this influence is mainly reflected erosion damage to the steel structure coating by sandstorm. As the coating has critical protection role to the durability of steel structure, the damage of coating will directly lead to reduce durability and safety of steel structure system. This paper researches on the anti-erosion mechanical properties of steel structure coating materials, and measures hardness, modulus , thickness and density of the coating by use of micron-indenter and traditional methods, the result shows that hardness is 2.1516MPa, modulus is 15.62MPa, thickness distribution is in the 800um ~ 1000um and density is 1.71g/cm³. This research result will provide the basis for preparation of anti-erosion coating and evaluation safety and durability of steel structures.

Abstract: High current pulsed electron beam (HCPEB), a novel high-power energetic beam technology, has been developed as a useful tool for surface modification of materials. In the present work, the effect of HCPEB treatment on microstructure and wear resistance of Al-15Si and ZK60-1Y Mg alloys was investigated. The results show that a supersaturated solid solution of (Al) and (Mg) is formed on top surface of melted layer induced by rapid heating and cooling during HCPEB process. In addition, the melted layer of approximately 5~11μm thickness is obtained on the ZK60-1Y Mg alloy surface. Wear resistance of Al-15Si and ZK60-1Y Mg alloys are significantly improved after HCPEB treatment. It is demonstrated that HCPEB technology has a good application future in enhancing surface properties of Al-Si and Mg alloys.

Abstract: In this paper, flame retardant Polyamide 6 (PA6) composites were prepared by nano-magnesium hydroxide (NMH) or its composites with melamine cyanurate(MCA) and ammonium polyphosphate(APP). Scanning electron microscopy (SEM) and X-ray diffraction (XRD) were used to analyze the structure of nano-magnesium hydroxide. The properties including tensile properties, molten index (MFI), rockwell hardness and density of flame retardant PA6 were analyzed. Orthogonal experiments were used to study flame retardancy of PA6 with NMH, MCA and APP. The results showed NMH had hexagonal orthorhombic crystal structure with size of 300×200×100nm. Density of polyamide 6 showed an upward trend when the content of NMH was increasing, the mechanical properties and hardness changed little while processing performance serious declined. The flame retardance of nitrogen-phosphorus -inorganic flame retardants was not desirable.

Abstract: In this study, welding of 2205 duplex stainless steel was carried out by first using plasma arc welding as root welding and then using tungsten inert-gas (TIG) welding and metal inert-gas (MIG) welding respectively as cover welding, Weldability of 2205 duplex stainless steel using two different the welding processes is investigated. Microstructure characteristics, mechanical properties, pitting corrosion resistance are made comparison between the weldment that is solution treated and that is not .Influence of heat input and the solid solution treatment on complex properties of welded joints is evaluated, and the solid solution treatment was conducted for both of the welded joints fabricated by the welding processes mentioned preciously.

Abstract: Power Demand-side Management (DSM) originated in the USA and was introduced into China later. As China's rapid economic development, social electric power energy demand is increasing, therefore, strengthen DSM, using reasonable price regulation and guide consumers the rational allocation of electricity methods and structure, so that we can achieve efficient use of power resources. From the perspective of electricity consumers and suppliers, this paper analyzed the relationship between them by constructing mathematical model, expected to provide some theoretical basis and practical guidance for the practice of government and power companies.

Abstract: Polypropylene (PP) nanocomposites with 0.1, 0.2, 0.5, 0.8, 1.0 and 2.0 wt% multi-walled carbon nanotubes (MW-CNTs) were prepared via meltcompounding in a twin-screw extruder followed by injection molding. The effects of MW-CNTs additions on the structure, mechanical and photo-oxidation behavior of PP were studied using X-ray diffraction (XRD), differential scanning calorimetry (DSC), tensile tests and FT-IR apparatus. XRD results showed that only α-PP crystals form in the PP/MW-CNTs composites. DSC results confirmed that the corporation of MW-CNTs enhanced the nucleation process on PP crystallization. Results of the tensile tests showed that before photo-oxidation, the tensile strengths of the samples increased with the increase of MW-CNTs contents when the MW-CNTs contents were less than 1% wt, whilst the tensile strength decreased at higher MW-CNTs contents (>1% wt). When subjected to photo-oxidation, the tensile strengths of the samples decreased with the increasing photo-oxidation time. The resistance to accelerated photo-oxidation of PP/MW-CNTs composites was also compared with the photo-oxidation behaviour of the original polypropylene sample. At short photo-oxidation time, such as under 250 h, the rates of carbonyl formation for the PP/MW-CNTs composites are similar to that observed for the original polypropylene but at longer photo-oxidation times the carbonyl formation increases for lower MW-CNTs contents (0.1, 0.2, 0.5 and 0.8% wt), and decreases for higher MW-CNTs contents (1 and 2% wt). It was found that the MW-CNTs showed both anti-degradation and pro-degradation effects at different concentrations.