Applied Mechanics and Materials Vols. 727-728

Abstract: In this paper, time interval between neighbored layers during the forming process of Surfacing Deposition Forming is defined. Then, surfacing deposition forming are experimented on Cu chilling pedestal and cast iron pedestal individually, the experimental data are processed with Matlab software to research the relationship between time interval and forming layer number, and t method of inspection is exploited to verify the validity of this relationship, even chilling effects on this relationship is studied at the same time. The result shows that: Time interval between neighbored layers would rise more and longer along with the progress of the forming process, and it has a linear relationship with layer number in generally; As the chilling effect, time interval is shortened prodigious, and its relationship with layer number changed to be a cubic curve function.

Abstract: In the engineering practice dry rubber modified asphalt mixture is easy to strip due to the poor adhesion between the rubber particles and asphalt. This paper describes a case study where the rubber-modified asphalt mixture mixed with hydrated lime, cement to improve the adhesion between the asphalt and rubber particles, and improve the road performance of the mixture. Then the additive dosage was determined through laboratory experiment and the pavement performance was verified. The result showed that: the water stability and high temperature stability could be evidently improved with the asphalt mixture added with these anti-stripping agents. And asphalt mixture with 1.5% hydrated lime had the best anti-stripping performance.

Abstract: Micro-milling orthogonal experiment of micro plane was done in mesoscale. Probability statistics and multiple regression principle were used to establish the surface roughness prediction model about cutting speed, feed rate and cutting depth, and the significant test of regression equation was done. On the basis of successfully building the prediction model of surface roughness, the diagram of surface roughness and cutting parameters was intuitively built, and then the effect of the cutting speed, feed rate and cutting depth on the small structure surface roughness was obtained.

Abstract: It has been proved that the mold filling under low pressure casting can be described by the second order nonlinear differential equations characterized by damping oscillations. To obtain higher accuracy of the velocity field, the mold filling process with damping oscillations should be considered. A computational model taking the liquid level droping in the crucible into account based on two phase flow for filling process of damping oscillations is presented in this paper. Hydraulic simulation with the particle image velocimetry was adopted to verify the numerical simulation result. It is proved that the nemuerical simulation results used the presented model perfecly match with the particle image velocimetry results. Liquid level droping in crucible is the main reason for damping oscillations in mold filling. Velocity oscilations can be eliminated when the melt flow across a sudden expansion section. The detailed flow field based on the presented model can provide guidance to optimize the process parameters.

Abstract: Colored binder was prepared by mixing aromatic oil with petroleum resin and functional polymers. Then the colored binder combined with pigment, aggregates, and additives resulted in colored asphalt mixture. Futher modification by nano-montmorillonite or coupling agent, higher pavement performance was chieved. The paving technical indexes of the mixture such as physical properties, moisture susceptibility, and high temperature stability were tested. The results demonstrate that the high temperature stability and moisture susceptibility can be satisfied with the requirements of hardscape projects including asphalt driveways, asphalt walkways, asphalt streets, asphalt bike paths, and asphalt walking paths.

Abstract: Basedon the assumption of related parameters in compressible packing model, thecompressible packing model was used for the calculation of the explosivespacking efficiency. The accuracy of the calculation was verified by experimentsand the relative error was 2.49%. Besides, the influence of content offineparticles and particle size distribution in explosives on stacking efficiencywas discussed. The results show that the stacking efficiency was increasingwith the particle size distribution increasing from 0~300μm to 0~700μm. Thepacking efficiency reached it’s maximum value when we only increased thecontent of fine particles to 40%. Therefore, the packing efficiency has arelation with particle size distribution of raw materials.

Abstract: Theinjection mould was designed through process analysis of the mouse shell.According to its size and structural features, the mould adopted double-cavitymould with two-step mechanism, latent type point gate feeding, lateralcore-pulling mechanism with inclined guide pillar, internal core-pullingmechanism with diagonal handspike. The practice use proved that everymechanism of mould worked flexibly with safety and reliable operation, qualityof plastic partmeted the requirements.

Abstract: The three-dimensional flow of seven holes variable-burning rate propellant in co-extrusion dies was simulated based on finite element method. The influence of long diameter ratio to interface radius and extrusion swell were analyzed. The result shows that keep the length to diameter ratio L/D₀ between 3.5 ~ 13, can control interface radius changes in the process of the extrusion processing co-extrusion processing .And D/D₀ reflect the viscoelastic fluid from the shear strain response ability.

Abstract: Traditional mechanics calculation and finite element analysis are performed to estimate the stress and distribution for each section of the telescopic arm in the operation of lorry crane. Through theoretical analysis, the working strength of the lorry crane telescopic arm can be obtained. Meanwhile experiment study is performed to verify the rationality of the finite analysis results, The results show that the telescopic boom has higher security, thus to provide theoretical support for design of the lorry crane telescopic arm.

Abstract: For many fuzzy factors in the industrialdesign of coal mine machinery and subjectivity in the process of evaluation,introduces the method of fuzzy AHP (Analytic Hierarchy Process) comprehensiveevaluation into the coal mine machinery. In thedecomposition of the evaluation index and its evaluation model of coal minemachinery industrial design. Through an example of an underground specialvehicle design scheme evaluation calculation, it verifies that this method isfeasible and effective.