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Wang D.,Key Laboratory of High Efficiency and Clean Mechanical Manufacture | Wang D.,Shandong University | Song Q.,Key Laboratory of High Efficiency and Clean Mechanical Manufacture | Song Q.,Shandong University | And 4 more authors.
International Journal of Advanced Manufacturing Technology | Year: 2017

In some special surgeries, e.g., burnt necrotic tissue removing process and skin grafting process, the cutting edge of scalpel moves along the tangential direction of tissue surface to achieve the cutting of biological tissue. This cutting pattern, which is similar with the turning process of metal material, is essential different from the vertical cutting presented in literatures. As a first endeavor, the cutting characteristics along tangential direction of porcine tenderloin surface are investigated experimentally, where the bottom surface of tissue is fixed and the top surface is free. A set of advanced devices especially for ex vivo porcine tenderloin cutting, which can easily adjust the variable under different operating conditions, are designed and manufactured. The real-time device records quantitatively the cutting forces and tissue deformations, which is for evaluating the cutting energies and the fracture toughness, and analyzing the whole cutting process in detail. Additionally, a compression test device is designed for performing a standard component compression experiment, which is used to evaluate the tensile yield stress and the pain degree. A novel quantitative metric is proposed for predicting the pain degree (PDI) with a typical compression test. The relationship between the stress and the pain feeling is presented by the compression test of the particular sample. © 2017 Springer-Verlag London


Liu H.,Shandong University | Wang Z.,Shandong University | Wang Z.,Key Laboratory of High Efficiency and Clean Mechanical Manufacture | Fang S.,Shandong University | Li C.,Shandong University
Mathematical Problems in Engineering | Year: 2017

A constrained low-cost SINS/OD filter aided with magnetometer is proposed in this paper. The filter is designed to provide a land vehicle navigation solution by fusing the measurements of the microelectromechanical systems based inertial measurement unit (MEMS IMU), the magnetometer (MAG), and the velocity measurement from odometer (OD). First, accelerometer and magnetometer integrated algorithm is studied to stabilize the attitude angle. Next, a SINS/OD/MAG integrated navigation system is designed and simulated, using an adaptive Kalman filter (AKF). It is shown that the accuracy of the integrated navigation system will be implemented to some extent. The field-test shows that the azimuth misalignment angle will diminish to less than 1°. Finally, an outliers detection algorithm is studied to estimate the velocity measurement bias of the odometer. The experimental results show the enhancement in restraining observation outliers that improves the precision of the integrated navigation system. © 2017 Huisheng Liu et al.


Jin D.,Shandong Polytechnic University | Liu Z.,Shandong University | Liu Z.,Key Laboratory of High Efficiency and Clean Mechanical Manufacture
International Journal of Advanced Manufacturing Technology | Year: 2013

FGH95 is one kind of powder metallurgy (PM) superalloy which has excellent mechanical properties at high temperature. It has been developed for turbine disc applications to improve aeroengine efficiency under higher operating temperatures. However, this kind of superalloy is very difficult to machine because of its poor thermal diffusivity and work-hardening properties during the machining process. The machining process can lead to damage of the machined surface and subsurface. Thus, the purpose of this paper was to investigate damage of the machined surface and subsurface in hard machining of FGH95 PM superalloy. Orthogonal milling experiments using coated carbide inserts were carried out on a CNC machining center. The machined surface was observed and recorded using an optical microscope, white light interferometer, and scanning electron microscope. Machined surface defects were recorded and analyzed. The effects of cutting speed on machined surface roughness, white layer thickness, plastic deformation, and microhardness were investigated. The research results show that better surface roughness can be generated at higher cutting speeds, while several defects appeared on the FGH95 machined surface. White layer thickness and machined surface microhardness increase with the cutting speed. Also, plastic shear strain in the machined surface layer increases with cutting speed. The depth of plastic deformation decreases with the increase of cutting speed. These investigation results are essential for the evaluation of PM superalloy surface integrity and are significant for the prediction of PM superalloy service life. © 2013 Springer-Verlag London.


Wang B.,Key Laboratory of High Efficiency and Clean Mechanical Manufacture | Liu Z.,Key Laboratory of High Efficiency and Clean Mechanical Manufacture
Proceedings of the Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture | Year: 2014

Serrated chip is the frequent chip morphology during high-speed machining of ductile materials, while the mechanism of serrated chip formation still remains some ambiguous aspects. This article presents the investigation of chip morphology from the viewpoint of chip free surface and cross section. Experiments of orthogonal cutting hardened AISI 1045 steel and 7050-T7451 aluminum alloy were carried out. The cutting speed of AISI 1045 steel was varied from 100 to 1000 m/ min, while 7050-T7451 aluminum alloy was machined at the cutting speed of 100-2500 m/min. The feed rate per tooth was varied from 0.025 to 0.20 mm/z corresponding to each experimental cutting speed. The research shows that the microstructure of chip free surface evolves from lamellae to folds and then to dimples. According to the experimental results, a new model of serrated chip formation based on mixed mode of ductile fracture and adiabatic shear is proposed. For the "ductile fracture-adiabatic shear" serrated chips, two distinct zones of ductile fracture and dimples were observed on the slide surface of serrated segments. Through studying chip morphology evolution under different combinations of cutting speed and feed rate, it is found that the degree of chip segmentation has positive correlation with the two parameters. The concept of "critical cutting load" is then proposed to illustrate the conditions under which serrated chips may occur. And the critical cutting load of AISI 1045 steel and 7050-T7451 aluminum alloy is determined by experiments as 0.024 and 0.10 m2/(min z), respectively. © IMechE 2013.


Mi Y.Z.,Shandong University | Zhou Y.Q.,Shandong University | Wang L.,Key Laboratory of High efficiency and Clean Mechanical Manufacture
Advanced Materials Research | Year: 2014

Acceleration signals at the mounts of an excavator cab are collected and analyzed, on the basis of which causes of peak values in the sound pressure level(SPL) at the driver's right ear(DRE) are discussed. A damping material layer made up of chlorobutyl rubber is arranged to the cab's panels by simulations according to results of panel acoustical contribution analysis, which indicates a great decline of the SPL peak values. © (2014) Trans Tech Publications, Switzerland.


Yin J.,Key Laboratory of High Efficiency and Clean Mechanical Manufacture | Zhang J.,Key Laboratory of High Efficiency and Clean Mechanical Manufacture | Wang W.,Key Laboratory of High Efficiency and Clean Mechanical Manufacture | Ren X.,Key Laboratory of High Efficiency and Clean Mechanical Manufacture
Polymer Composites | Year: 2015

With excellent vibration alleviating properties, resin mineral composite (RMC) has attracted special attention in the field of mechanical engineering. However, applications of RMC are restricted because of its limited mechanical strength. In this research, the glass fiber (GF) was added into RMC to increase its mechanical strength, and the effect of the length and mass fraction of GF on the mechanical strength of GF/RMC were investigated. Results showed that the compressive strength and flexural strength of RMC first increased and then decreased as the length and mass fraction of GF increased. In order to improve the interfacial bonding between GF and RMC, the GF was subsequently treated by ultrasonication, oxidation, and silanization. And three types of treated GF, i.e., ultrasonic treated GF (U-GF), ultrasonic and oxidation treated GF (O-GF), and ultrasonic, oxidation and silanization treated GF (S-GF) were obtained. Among these three types of treated GF, the S-GF exhibited superior reinforcement in RMC. In addition, the effect of oxidation parameters on the mechanical strength of S-GF/RMC was investigated. In the case of sodium hydroxide oxidation, the optimum mechanical strength of S-GF/RMC was achieved when the S-GF was treated in 1.5 mol/L sodium hydroxide for 3 h at 40°C, in which the compressive strength and flexural strength of S-GF/RMC increase by 17.5% and 20.8% compared to neat RMC, respectively. In the case of hydrogen nitrate oxidation, the best mechanical strength of S-GF/RMC was achieved when the S-GF was treated in 1.5 mol/L hydrogen nitrate for 5 h at 80°C, in which the compressive strength and flexural strength of S-GF/RMC increased by 11.2% and 18.1% compared to neat RMC, respectively. © 2015 Society of Plastics Engineers.


Liu R.L.,Shandong University | Liu R.L.,Key Laboratory of High Efficiency and Clean Mechanical Manufacture | Zhu H.G.,Shandong University
Advanced Materials Research | Year: 2014

With STEP-NC (ISO 14649) being gradually accepted as new standard for programming computerized numerical control (CNC) machine tools, new technologies and computer systems in the design and manufacturing process chain are emerging, and conventional systems are reshaping, to support interoperable and intelligent manufacturing. This paper addresses issues and solutions for the adaptation. In the first place, a strategy for adapting legacy CNC turning machine tools to the emerging standard is presented. In the second place, the new data model is analyzed and a practical way to retrieve and extract manufacturing information from the STEP-NC part program for turning process is presented. In the third place a workable approach to calculating the cutting force and chip load in turning operations is presented based on the mechanistic modeling method. Finally the proposed approach is implemented in a prototype system and tested with an example STEP-NC program for turning, which shows not only the feasibility of the proposed approach for information extraction and process evaluation, but also the possibility of using simple transitional systems to bridge the gap between the sophisticated STEP-NC part program and conventional CNC machines. © (2014) Trans Tech Publications, Switzerland.


Yin J.,Key Laboratory of High Efficiency and Clean Mechanical Manufacture | Zhang J.,Key Laboratory of High Efficiency and Clean Mechanical Manufacture | Zhang Y.,Key Laboratory of High Efficiency and Clean Mechanical Manufacture | Wang W.,Key Laboratory of High Efficiency and Clean Mechanical Manufacture
Journal of Applied Polymer Science | Year: 2016

Particulate-filled polymer composites (PFPC) have received a great deal of attention in the field of precision machine tools because of their excellent vibration-alleviating property. However, applications of PFPC in the field of precision machine tools are restricted by its limited mechanical strength. The pores in PFPC are one of the key influences on its mechanical properties, such that the porosity determines the overall mechanical properties of the PFPC directly. In this paper, the relationship between porosity and mechanical properties (compressive strength, flexural strength, elasticity modulus) and damping ratio of PFPC was studied systematically. A strong correlation between the porosity and the mechanical properties and damping ratio of PFPC was found. The results show that the mechanical properties (damping ratio) of PFPC deteriorated (increased) dramatically with increasing porosity. An empirical formula was proposed for the relation between the porosity and the mechanical properties (and damping ratio) of PFPC. © 2016 Wiley Periodicals, Inc.


Zhang P.R.,Shandong University | Zhang P.R.,Key Laboratory of High Efficiency and Clean Mechanical Manufacture | Liu Z.Q.,Shandong University | Liu Z.Q.,Key Laboratory of High Efficiency and Clean Mechanical Manufacture
Materials Science Forum | Year: 2014

The paper investigates the effects of cutting edge preparation on cutting force, cutting temperature and tool wear for hard turning. An optimized characterization approach is proposed and five kinds of cemented tools with different edge preparation are adopted in the simulations by DEFROM-2D™. The results show that both the forces and cutting temperature on the rake face climb up and then declines with the increasing of factor K (Sγ/Sα). While the temperature on flank face decrease with the increasing of the factor K. When the cutting conditions are identical, flank wear reduces while crater wear exacerbates before easing with the increasing of the factor K. The simulation results will provide valuable suggestions for optimization of cutting edge preparation for hard turning in order to obtain excellent machining quality and longer tool life. © (2014) Trans Tech Publications, Switzerland.


Lv K.,Shandong University | Huo M.,Shandong University | Li F.,Key Laboratory of High Efficiency and Clean Mechanical Manufacture
Applied Mechanics and Materials | Year: 2013

In order to achieve the precise control of the compressed air foam proportioning on the fire engines, in this paper, the PIC microcontroller and the fuzzy control algorithm are used to design the microcontroller-based foam proportioning hybrid fuzzy control system. Taking into account the system cost and ease, we use the software to implement the fuzzy control of DC motor. The controller learns from the experience of skilled operators, and forms fuzzy control rules, finally we identify a number of important control parameters in this paper. The experimental results show that the fuzzy control system can achieve precise control of the mixing ratio. © (2013) Trans Tech Publications, Switzerland.

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