Applied Mechanics and Materials Vol. 415

Abstract: By analyzing the enginegenerator units (EGU) work characteristics of electric drive armored vehicles, engine is controlled running along the optimum fuel curve. Voltage regulation of DC side and generator working condition are optimized through designing voltage space vector PWM (SVPWM) rectifier control system. Adopting rule-based method to solve the nonlinear problem during multi-power source coordination output, developed the multi-power source coordination output control strategy, satisfied the load power needs and the working state of the EGU is optimized.

Abstract: Aiming at the steering special requirement of in-wheel motor drive wheeled vehicle, the dual-steering control is adopted. The target of control system is the vehicle yaw rate, and active disturbance rejection controller is designed. Yaw moment torque is produced by adjusting the both sides of motor torque output to achieve the target of reference yaw rate. The vehicle kinetics model is built in the Adams, and the co-simulation model is designed base on the Adams and Matlab. The results of simulation demonstrate that the dual-steering control increased the vehicle outboard power output and decreased the steering radius, and improve the steering agility of the vehicle.

Abstract: According to the indicator diagram of damper, the indicator diagram plumpness was proposed as a quantitative index, and its mathematical relationships with the sprung mass acceleration, suspension dynamic travel and tire dynamic load were built. Moreover, the influence of the total area on suspension characteristics was analyzed in time domain and frequency domain. The results show that, the increase of the indicator diagram plumpness can effectively restrain the variation of suspension dynamic travel and tire dynamic load, meanwhile, the body acceleration will be enlarged. Excessive indicator diagram plumpness also affects the dynamic tire load distribution in frequency domain, and it will decrease the driving security. Therefore, it should be reasonably selected from the performance indicators, which is based on the requirement of vehicle demand in the design process.

Abstract: In the process of military vehicle design and modification, because of the dynamotor, oil pump and other load demands, installation of power take off (PTO) is an common project which will meet different needs of users. The paper designs and summarizes the military field used in conjunction self-propelled dynamotor system of kitchen vehicle's design project, process, performance testing and test data and etc.

Abstract: Morphing surface mesh employing a parametric model for the aerodynamic shape optimization of a sedan is presented. This study solved the problem of non-linear deformation in modeling surface morphing by volume mesh, and solved the divergence problem due to bad mesh quality, using automatic grid generation method based on CAD model, in calculation. The optimization process consists of three stages: Design of Experiments (DOE), Approximate Model, and optimization algorithm execution. The optimization process was realized by an automatic optimization system consisting of multiple software platforms. The optimal model's aerodynamic drag coefficient is 10.56% decreased though optimization, and the hood is identified as the major factor in this research.

Abstract: The objective of this research is to investigate the effect of parameters on the microstructure and mechanical properties of friction stir welded butt joints of dissimilar aluminum alloy sheets between Semi-Solid Metal (SSM) 356 and 6061. The base metal of SSM 356 and 6061 was located on the advancing side and on the retreating side, respectively. The cylindrical pin was used as the welding tool geometry. Friction stir welded using different tool rotation speed (710, 1,000 and 1,400 rpm) and welding speed (80,112 and 160 mm/min). From investigated, the maximum average tensile strength of 175.40 MPa was achieved for the joint produced at tool rotation speed 1,400 rpm, welding speed 112 mm/min. Metallurgy and welding structures occurred of aluminum composite material will consist of two types of definition than the base metal.

Abstract: Aim for calculating stress intensity factor (short for SIF) of different width plates with edge crack, and the change tendency between different widths and SIF, the crack model is built by finite element software, and the SIF change tendency line with different width plates is got. It is seen from the von Mises stress cloud chart of ANSYS that the deformation of plate is effected by crack; as the decreasing of width, SIF is increasing. When the width of plate is down to 3/8, SIF is increasing fiercely, that means, the plate at this time has already reached the edge of fracture. If continue loading the stretch, the crack will be apparent on the plate. And the curvature equation is got by index decay adapting.

Abstract: Specification cutting tools durability made of cutting ceramic in machining process of steel 80MoCrV4016 is very important for economics of small and medium-sized enterprises, because cutting tool durability is factor that significantly affects the budget of these enterprises. This problematic is determined for small and medium-sized manufacturers of bearings, because steel 80MoCrV4016 is most commonly used for production of bearings. Durability of cutting tool defines lifetime of this cutting tool and it determines its suitability for select technological operation. Especially for cutting ceramic is necessary to define durability dependence on available set of cutting speeds and to determine lifetime of tools made of cutting ceramic. Technical science defines a lot of different factors, that they may be cause of shorter cutting tool lifetime. For increase cutting tool durability is necessary maximally possible elimination of these factors. Determination of cutting tool durability is very important, because provides comprehensive information how to determine appropriate technological conditions for selected cutting tool. In engineering is for determination of cutting tools durability used T-v_c dependence. The article describes process how to create durability dependence for cutting tools made of cutting ceramic by means of T-v_c dependence in machining process of steel 80MoCrV4016.

Abstract: Technical science defines a lot of different factors, that they may be cause of shorter cutting tool lifetime. For increase of cutting tool durability is necessary maximally possible elimination of these factors. Determination of cutting tool durability is very important, because provides comprehensive information how to determine appropriate technological conditions for selected cutting tool. The analytical expression of dependence represents very important part of experiments, because all tested processes can be described and defined by formula. These instructions, how to proceed in experiments are obtained in standard ISO 3685. Very important and often used standard ISO in engineering practice is standard ISO 3685. The main part of this standard is T-v_c dependence for cutting materials. In standard ISO 3685 are included cutting materials made of high speed steel, sintered carbide and cutting ceramic. The article describes process how to define and to analytically express T-v_c dependence for cutting tools made of ceramic in machining process of steel 80MoCrV4016.

Abstract: Steel material is one of the indispensable raw materials for human, and its mechanical property is one of the most popular measurements used for weighing the mass. In this paper, we study the microstructure of steel how to affect the mechanical property. Some conclusions are drawn about the structure of pearlite, bainite and martensite have different mechanical properties while the constitution of steel is regular, and we can vary the mechanical properties of steel through the way of metal heat treatment.