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It take some problems for CNC drill machine and machine center on automatic production line which high quality expected, especially more and more hard-to-cut materials such as titanium alloy, heat-resisting alloy and composite product have been used extensively as the industrials of astronavigation manufacture, atomic energy, etc grow.
The common twist drills which may have a good character when drilling common materials could have a worsening performance when it is used to drill the new materials.
The main progress directions of the subject are optimizing drill's structure, improving drill's material and coating [2].
Acknowledgements This investigation supported by the Natural Science Fund of Jiangsu province China.
Kang: Journal of Daliang University of Technology, Vol.38 (1998) No.4, pp.88

Numerical Simulation Analysis of Spinning Forming Process of Tubeless Steel Wheel on Technical Parameters Dasen Bi1,3,a, Guang Yang1,b, Liang Chu1,2,c, Jian Zhang1,2,d 1.School of Materials Science and Engineering Tianjin University of Technology Tianjin 300384, China 2.Key Laboratory of Display Materials & Photoelectric Devices（Tianjin University of Technology）, Ministry of Education,Tianjin 300384, China 3.Tianjin Key Lab for Photoelectric Materials & Devices,Tianjin 300384,China atjbds@sina.com, bsun5sun5sun@163.com,cchuliangszhm@163.com, dzhang_jian_99999@126.com Keywords: Tubeless Steel Wheel; Spinning Roller's Rotational Speed; Coefficient Of Friction Between The Spinning Roller And The Blank Abstract.
If the rotation rate of mandrel is too low, the forming of blank is unsteady; if the rate is too high, the rib of the steel wheel would be made too thin.So the reasonable rotation rate should be designed according to the material and thickness of blank and diameter of mandrel.Generally, we choose 400~600r/min[4] for steel.When the diameter of madrel is bigger and its thickness is smaller, we choose the smaller rate,otherwise we choose the bigger one.
Table 1 constants of simulation parameters Material of blank AISI-1010,COLD[70F(20C)] Coefficient of friction between blank and mandrel 0.12 Temperature 20° Rotation rate of mandrel 400r/min Feed speed of spinning roller 1mm/s Step number 200 Table 2 variables of simulation parameters Rotation rate of spinning roller 1 rad/sec; 2rad/sec; 3rad/sec; 4rad/sec; 5rad/sec; 6rad/sec Coefficient of friction between blank and spinning roller 0.3; 0.5; 0.7 The spinning process is a much complex plastic forming process with multi-factors coupling interactive effects, companying with the characteristics of large-scale deformation, local deformation zone and high nonlinearity.Spinning is designed to forming a groove around the blank using a roller which feeds radially first and then rotates around the mandrel, as shown in Fig.6.
Table 4 Quality of the forming steel wheel under different technical parameters quality f r 0.3 0.5 0.7 1rad/sec well well well 2rad/sec no wrinkle basically no wrinkle basically no wrinkle basically 3rad/sec a little wrinkle a little wrinkle a little wrinkle 4rad/sec obvious wrinkle obvious wrinkle obvious wrinkle 5rad/sec obvious wrinkle obvious wrinkle obvious wrinkle 6rad/sec obvious wrinkle obvious wrinkle obvious wrinkle Acknowledgements This work was supported by Ministry of Industry and Information Technology of the People’s Republic of China support project under Grant No. 2010ZX04004-121, and Tianjin Key Subject for Materials Physics and Chemistry.
Dean, J.Lin: International Journal of Machine Tools & Manufacture, 2003,(43): 1419-1435 [3] Japan Plastic Processing Institute: Spinning forming technology [M].

Introduction Among the large family of EAP (electro-active polymers) materials, IPMC with the advantages, e.g. low voltage, flexible, large bending, is considered as the conceivable actuator materials for biomimetic applications [1-5].
Barbar et al [13] developed a transducer consisting of multiple lays of ionic polymer materials.
National Science Foundation (50905037) and the Central College Fund of Harbin Engineering University(HEUCF140713).
Aw, A compliant surgical robotic instrument with integrated IPMC sensing and actuation, International Journal of Smart and Nano Materials 3 (3) (2012) 188-203
Kim, Muscle-like linear actuator using an ionic polymer-metal composite and its actuation characteristics, Smart Structures and Materials & International Society for Optics and Photonics (2006) 616820-616820-8.

Dam construction material is mainly Andesite Rock, and the dam site is located in a wider river valley with a width-to-depth ratio of 9.5.
Material parameters for dynamic computation are shown in Tables 1 and Tables 2.
Table 1 Parameters of computation Dam material Km m1 Primary rockfill material 2374 0.587 secondary rockfill material 2128 0.583 Transition rockfill material 2604 0.572 Table 2 Parameters of Dynamic shear modulus and Damping ratio Dam material Parameters 5×10-6 1×10-5 5×10-5 1×10-4 5×10-4 1×10-3 5×10-3 1×10-2 Primary rockfill material Gd/Gdmax 0.992 0.983 0.921 0.854 0.539 0.369 0.105 0.055 λd 0.004 0.007 0.031 0.054 0.129 0.157 0.189 0.194 secondary rockfill material Gd/Gdmax 0.993 0.986 0.933 0.875 0.583 0.412 0.123 0.065 λd 0.003 0.006 0.026 0.046 0.123 0.156 0.198 0.204 Transition rockfill material Gd/Gdmax 0.992 0.984 0.927 0.864 0.559 0.388 0.113 0.060 λd 0.003 0.006 0.027 0.047 0.120 0.148 0.183 0.188 Seismic wave input.
The research work is partly supported by grant No. 2008BAB29B02 from the National science and technology support plan of China.
High earth-rock dam seismic research progress[J], Journal of Anhui Construction Industry Institute college Vol.17 (2009), p. 1 [3] ZHAO.

And the simulations of the interaction process between shot and material have been performed.For aluminum alloy material Al2024-T3, the surface roughness induced by shot peening is studied.
Al 2024-T3 was chosen as the target material.
As material properties:the elastic modulus E=70GPa,Poisson’s ratio and density 2700 kg/m3,respectively.
The initial material surface is assumed to be an ideal plane.
Journal of Materials Processing Technology, 2008,(203):401-409 [6] H.W.

Materials and Methods The white cast iron was smelted with pig iron, scrap steel, ferrochromium and ferromanganese.
Table 1 Chemical composition for the experimentalwhite iron [wt.%] C Cr Si Mn 2.6 1.0 1.1 0.8 Table 2 Technology for heating processing for different treatment Treatment Austenitizing temperature [˚C] Heating time [min] Quenching medium Tempering /isothermal temperature[˚C] Tempering /isothermal time[min] Martensitic quenching 920 120 32 engine oil 220 120 Austempering 940 120 50%KNO3+50%NaNO2 300 150 Annealing 950 240 - - - Results and Analysis Effect of modification on microstructure and mechanical properties of materials.Fig.1 shows the optical microstructure of the non-modified as-cast white cast iron.From Fig.1, it can be seen that the carbides distribute in the form of thick and dense continuous network.
Fig.1 Optical microstructure of Fig.2 Optical microstructure of non-modified as-cast white cast iron modified as-cast white cast iron Table 3 The harness and the impact toughness of modified and non-modified as-cast white cast iron Materials Hardness[HRC] Impact toughness[J/cm2] Non-modified white cast iron 50.1 2.2 Modified white cast iron 55.2 5.1 Effect of heat treatment on microstructure and mechanical properties of materials.Fig.3 shows that the optical microstructure of annealing modified white cast iron.From Fig.3 it can be seen that the amount of carbide decrease,the form of carbide is block or strip and the layer spacing of pearlite matrix become larger.
SARE:JOURNAL OF MATERIALS SCIENCE.35(2000),p.2069 [5] Bing Liu:Hot Working Technology.

As a hot-diamond tip is used, the new instrument can measure both electrically conductive and non-conductive materials, overcoming the limitation of conventional SThMs.
References [1] Hazel Assender and Kyriakos Porfyrakis: How Surface Topography Relates to Materials' Properties.
Science. 297 (2002), pp. 973-976
Journal of the European Ceramic Society. 28 (2008), pp. 15-20
Materials Characterization. 48 (2002), pp. 11-36

Low Dielectric Loss Polymer-Ceramic Composites for Wireless Temperature Sensation Li Zhanga, Zhenxing Yueb and Longtu Lic State Key Laboratory of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University, Beijing100084, China.
An ideal temperature-dependent material used in sensing antennas should have a large temperature coefficient, high relative permittivity, and low dielectric loss.
For the 30% volume fraction HDPE/BNT composite, aL is 63ppm/˚C andter is -370ppm/ ˚C, hence the tf is -122ppm/˚C , which is much larger than conventional microwave ceramic materials, such as -40 ppm/ ˚C of alumina.
Ratheesh, Preparation and microwave characterization of BaNd2-xSmxTi4O12 (0≤x≤2) ceramics and their effect on the temperature coefficient of dielectric constant in polytetrafluoroethylene composites , Materials Research Bulletin 44 (2009) 2022–2026 [9] C.C.
Huang, Fabrication of circular polarization antenna on PEI/BSTZ composite substrate for the application of UHF-RFID reader, Journal of The Electrochemical Society, 156(12) (2009) 197-200.

Choice for the structure and materials of thread.
[p] is the allowable stress of material (MPa), [p]=22MPa in this design.
Calculating the allowable tensile stress of screw material [σ] (6) Where, σs is the yield limit of screw material (Mpa), σs= 355MPa, in this design, s is safety coefficient, s=4 in this design.
The cast aluminum bronze nut was used in the design, material allowable shear stress [τ]=35MPa,τ<[τ].
[8] Xie Haidong, Yu Yan, Dynamice Study on Horizontal Screw Jack, Journal of Netshape Forming Engineering,2012(3), vol 4: 78-81

Microstructures and Toughening Mechanisms of Y2O3 Doped Al2O3/ZrO2 Eutectic Composite Ceramics Prepared by SHS Melt-growth Process Long Zhang 1,a, Zhongmin Zhao 1,b, Yigang Song 2,c and Weiguo Wang 2,d 1 Institute of Advanced Materials, Mechanical Engineering College, Shijiazhuang, 050003, China 2 Science Research Department, Mechanical Engineering College, Shijiazhuang, 050003, China E-mail: zhao_zhongmin@163.net Keywords: Al2O3/ZrO2 composite ceramics, rod-shaped sapphires, nano-micron fibers, melt-growth, toughening Abstract.
In recent years, with the rapid advances in aerospace materials, the novel unidirectional solidified oxide/oxide eutectic composites of superior flexural strength, thermal stability and creep resistance at high temperature have been reported [3-6], and the systems of materials involve Al2O3/YAG, Al2O3/GAP, Al2O3/ZrO2 (Y2O3), Al2O3/YAG/ZrO2 and so on.
Raw materials were prepared from high purity (>99.9%) CrO3, Al, ZrO2, Y2O3 and SiO2 powders with size 0.074~0.147mm, and the combustion systems were prepared according to mass ratio of (CrO3 +Al)=68%, mass ratio of ZrO2 (4Y)=28%, and mass ratio of SiO2=4%, in which the (CrO3+Al) subsystems were prepared according to chemical ratio as shown in Eq.1.
Waku: Journal of Crystal Growth Vol. 231 (2001), p.179 [7] Z.
Zheng: Key Engineering Materials Vol. 280-283 (2005), p. 1053 [8] Z.