Advanced Materials Research Vols. 785-786

Abstract: The surface free energy of the asphalt was determined using the Owen-Wendt method by determining the contact angles between asphalt and different probe liquids. The effect of rock asphalt on the surface free energy of asphalt was measured. The results indicate that the rock asphalt increase the surface free energy of asphalt, which enhances the moisture damage resistance of asphalt.

Abstract: The product corrosion causes safety issues in flight vehicles and capital losses in aerospace industry. Since some geometrical surfaces and shapes such as hidden slot and pocket structure can easily contain moisture droplets and air impurity, the corrosion caused by chemical composite in aerospace products can be accelerated leading sudden flight vehicle failure and even personal fatal injury. Nanoparticle coating technology is a relatively new and efficient methodology in anti-corrosion since it can distribute very small material particles in complex geometrical structures to produce extremely durable and very strong surface coating to significantly decrease product corrosion. This paper studies the anti-corrosion mechanism in order to reduce corrosion damage by applying computer-aided simulation and prototype testing to verify nanoparticle coating performance. Both computer-aided simulation and prototype testing show close results which validate the methodology introduced in this research and demonstrate superior corrosion-resistant performance of nanoparticle coating to current regular coating methodologies.

Abstract: In order to investigate the influence of magnetron sputtering parameters on surface properties, hardness and friction tests were carried out for TiN-coated bearing steel sputtered under different deposition times varied from 5 to 30 minutes. Hardness of coated specimens was increased by magnetron sputtered and markedly affected by deposition time. Coated TiN thin films on the surface can also effectively improve the friction properties of the bearing steels. The deposition times from 5 to 10 minutes is the most suitable condition to improve the surface friction properties and hardness for bearing steel under the sputtering power with 200W.

Abstract: The SiO₂/PU composite coatings were prepared by the bionic methods. First, nanosilica (SiO₂) was prepared by sol-gel method using tetraethyl orthosilicate (TEOS) as the precursor. Then, by a simple spray process. The formation mechanism and the structure characteristics of the coating were analyzed. The coating surface was characterized using scanning electron microscopy (SEM). The effect of the content of the SiO₂ and the dosage of PU and PEAC on the coating structure and contact angle was also studied. The results show that the coating surface has the similar micro-nanostructure with a lotus leaf, and the SiO₂ content is 9%, the total content of PU and PEAC is 15%, that the contact angle of coating can reach 161°and rolling angle can reach 3°, and that the SiO₂/PU composite coating possesses good super-hydrophobic properties.

Abstract: An orientation distribution function is adopted to describe three-dimensional orientation distribution of short fibers suspensions in extensional flow. A mathematical model of evolution process on fiber orientation distribution function is established by analytical method. Numerical simulation is also used to describe two and three dimensional orientation distribution of fibers. Therefore, analytical solution of differential equation on forecast fiber orientation distribution is deduced.

Abstract: This paper shows a new type of manual SHS welding rod for normal carbon steel, called the pulse combustion rod. The structure and constitution of the pulse combustion rod was designed after the analysis of the problems and insufficiency of the normal manual SHS welding rod (normal combustion rod for short) in the vertical welding. Then the low carbon steel as the base metal was used for vertical weld experiment. Analysis of SEM, XRD and EDS shows that weld seam is composite of Fe-riched phase and Cu-riched phase, with much α-Fe but a little FeNi, ε-Cu and Cu_0.81Ni_0.19 contained in Fe-riched phase, and with much ε-Cu but a little Cu_0.81Ni_0.19, α-Fe and FeNi contained in Cu-riched phase. The interfacial adhesion between Cu-rich phase and Fe-rich phase is effectively improved for the Ni content in two phases is roughly the same. The weld seam alloy has a good bond with the base metal. The mechanical properties test of weld joint present that tensile strength is up to 367MPa and the hardness of weld alloying zone is HV143.8.

Abstract: A dynamic 3D thermal and mechanical Simulation of CO2 welding 409 stainless steel multi-Crossed parts was carried out by using the software SYSWELD. A double ellipsoid heat source model of CO2 arc welding was explored and fitted with the Heat Source Fitting tool. The transient stress and strain fields of 409 stainless steel multi-crossed weld joint under two kind of welding sequences were obtained by loading the simulated temperature field, which helps to decrease the residual stress and deformation of 409 stainless steel multi-Crossed parts welding.

Abstract: Cu-Ag alloy is using for Cu Cladding Al Contact Wire, it was formed by continuous extrusion. The flow stress behavior of Cu-Ag alloy for Cu cladding Al contact wire was studied by hot compression experiments using Gleeble-1500 hot simulation machine. The flow stress mathematical models of the Arrhenius relationship of the hyperbolic sine function are established including hot deformation activation energy, deformation temperature and strain rate. The results may be using in numerical simulation for forming.

Abstract: Multi-stage horizontal well fracturing with several perforating clusters in each stage is an important completion technique in tight gas and shale gas reservoirs. Due to the stress field interference, different perforation parameters and unevenly distributed cluster distance lead to individual fracture pressure, which determines whether the clusters can all be initiated during the fracturing process. The ABAQUS software can be used to create the 3D finite element model of horizontal multi-stage fracturing with several clusters and to analyze the fracture pressure influenced by different parameter set of helix perforation, such as phase angle, tunnel diameter, tunnel depth and perforating density. Based on the results of perforation parameter analysis, the simulation method can be validated with actual treatment data from Jilin oil field.

Abstract: The basic hypothesis of this article focuses on the study changes in mechanical properties of stainless steels ELC X01Cr18Ni10Ti under surface finish when drilling. The problem of drilling holes with diameter D=3 to 10 mm resides in the fact that 30 to 40% of these holes do not comply with prescribed requested requirements1. This article presents the results of experiments focusing on the study of the damage process in helical drills with diameter d=6.0 mm when drilling into austenitic stainless steel ELC X01Cr18Ni10Ti. This study also includes an analysis of accompanying phenomena in the cutting zone by measuring some selected parameters.