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The turning accuracy of Machine Tool Spindle and grinding process system were analyzed to guarantee the grinding accuracy and cutting accuracy of the whole machine material.
Table 1 Geometric accuracy requirements Testing Item Error Source Radial flop of spindle journal (permitted amount: 1.5μm) Flop of spindle blade shoulder (permitted amount: 1.5μm) Radial flop of spindle cone location hole (permitted amount: 1.5μm) Cylinder detected surface 1.roundness error 0 0 2.offset error between the axis of detected surface and rotating axis 0 0 3. deviation of the rotating axis 0 0 Plane detected surface 4.flatness error of the detected surface 0 5. verticality error between detected surface and rotating axis 0 6.periodic axial displacement of rotating axis 0 0 Table 2 Error modified of two technique methods Error of the detected surface Technique method 1.Space directional fitting method 2. self-grinding method Cylinder detected surface 1.roundness error Can not be modified partly modified 2.offset error between the axis of detected surface and rotating axis Obviously modified Obviously modified 3. deviation
The accuracy of spindle part was higher than domestic common machine according drawing(The roundness of spindle bearing journal is 0.8μm, the coaxiality between the frontier bearing and the behind bearing is 1μm, the radial run-out is 0.8μm, the verticality between shaft shoulder and bearing surface axis is 1μm, the radial run-out between 30oC inner cone positioning core and bearing surface is 1.2μm ).The last three geometric accuracy of CG6120 lathe spindle assembled by space directional fitting method shown as Table 1 was difficulty to reach 1.5μm..
Reference [1] Zhao Rufu: Metal Mechanical Processing Technique Manual, Shanghai, Shanghai Science Technology Press (2004)

Based on the kinematics and material mechanics, the gripper motion is analyzed.
Acknowledgements This work was supported by the Priority Research Centers Programs through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology (2012-0005856) Corresponding Author Prof.
Roch: Journal of Micromechanics and Microengineering Vol. 13 (2003), p. 330 [4] Y.Zhou and B.
Popovic: Journal of Micromechanics and Microengineering Vol. 12 (2003), p. 430 [6] Specification of Miniature OEM motors: SQ-100-N (New Scale Tech.)

Material data.
Jonas, Prediction of steel flow stresses at high temperatures and strain rates, Metallurgical and Materials Transactions A 22 (1991) 1545–1558
Ortner, Recrystallization in Hot Working and Creep, Metal Science Journal 8 (1974) 161–167
Bambach, Conditions for Consistent Implementation of Flow Stress Models Incorporating Dynamic Recrystallization into Finite Element Simulation Codes, Materials Science Forum 762 (2013) 325–330
Part 1: The recovery technique, International Journal for Numerical Methods in Engineering 33 (1992) 1331–1364

Green concrete is a good solution for managing waste materials and using them in practical applications.
Material As per the guidelines code of ACI 318-11 [26], the various properties of the used materials in the concrete mixes were determined.
Tabchouche, Assessment of the PVC Waste Addition Effect on the Concrete Mechanical Performance, Journal of Composite & Advanced Materials/Revue des Composites et des Matériaux Avancés 33(2) (2023)
Yazdi, Waste steel wires modified structural lightweight concrete, Materials Research 17 (2014) 958-966
Lok, Mechanical properties of aramid/carbon hybrid fiber-reinforced concrete, Materials 14(19) (2021) 5881

Under the assumption of small displacement theory and linear elastic isotropic and homogeneous material behavior, the equation of motion of the body is (1) The displacement and velocity satisfy the initial conditions （2） The singular integral equation can be obtained by travelling characters of elastic wave and dynamic extension of Betti’s reciprocal theorem[1] (3) Where tj(q,t) and uj(q,t) are the stress and displacement, respectively, q∈S. t is time variable.
REFERENCES [1] P.K.Banerjee and R.Buttertield：Boundary Element Methods in Engineering science, McGraw –Hill.
[4]Xuejun.Zhao, Dynamiccrack starting Research Progress,, [J] Building Science, china, 2009, 7, p85-88 [5]Youlin.Liu, ,Dynamic response of the beam structure With a Crack, [J] Journal of sunyatsen university, china, 2012,10,p52-55

Introduction Significant advances in the field of building materials leads to increasingly frequent enforcement these high performance materials in real constructions.
The increasing the cost of input materials will significantly reduce the total volume and weight of structures.
We can also use some secondary raw materials like ground brick dust to complete the composition of composite.
In the context of global efforts to substitute the energy-intensive building materials by secondary raw materials is discussed the possibility of using ground bricks dust.
Kodur, High-Temperature Properties of Concrete for Fire Resistance Modeling of Structures, ACI Materials Journal/September-October, (2008)

Chinese Journal of Rock Mechanics and Engineering Vol. 15 (1996),p. 275-281, in Chinese
China Railway Science Vol. 30(2009),p. 51-56, in Chinese
Journal of Xi'AN University of Science & Technology Vol. 22(2002),p. 18-20, in Chinese
Chinese Journal of Rock Mechanics and Engineering Vol. 25(2006),p. 1502-1511, in Chinese
Journal of Tongji University (natural science) Vol. 36(2008),p. 460-465, in Chinese

Raw materials humidity is about 10%~15% before stirred.
[12] Xiaohua Yang et al. : NWE BUILDING MATERIALS.
[14] Qisheng Wu et al. : NWE BUILDING MATERIALS.
[15] Gengxin Chen, Jibo Liu: Housing Materials & Application.
[16] Huiqiang Xiang et al. : Journal of Liaoning Technical University.

Theoretical Analysis Micro-voids and micro-cracks are formed at the interfaces between different materials during fabrication of plastic packaging ICs, and the MC based on polymer materials is hydrophilic and porous, so it’s easy to absorb moisture when exposed to humid ambient condition [8,9].
Fick’s second law can be applied to describe the moisture diffusion process in polymer materials [10].
Due to the different CTE (a) of different materials, the thermal stress will occur in the heat transfer process.
The package is mainly composed of silicon die, conductive adhesive, lead frame and encapsulation materials, but some materials such as gold wires are ignored.
Tay, Modeling of interfacial delamination in plastic IC packages under hygrothermal loading, Journal of Electronic Packaging, vol. 127, (2005) 268-275

The model parameters of 1Cr-0.5Mo-0.25V stainless steel bolting material at 500°C have been determined, and the creep and stress relaxation behaviors have been calculated.
The relationship between the residual stress and time during stress relaxation of various different materials has been derived from the creep equations.
(3) where E is Young’s modulus, A, σ0, n, α, β are material parameters, H is the strain hardening function.
References [1] Jinquan Guo: Research on the Analysis and Prediction Methodology of High Temperature Stress Relaxation(Dissertation, East China University of Science and Technology, China, 2010) [2] M.
Price: Journal for Global Optimization Vol. 11(1997), p.341 [9] NRIM Creep Data Sheet No. 44, National Research Institute for Metals, Tokyo (1997).