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In this paper, the machinability of surface is introduced, and it is obtained from the analysis that the main macroscopic factors of tool premature failure are forging defects.
The dynamic change of tool is leaded by the forging defects in the cutting process, so the tool is affected by forging defects (as shown in Fig. 3).
So the tool is always affected by dynamic mechanical impacts in the cutting process.
It is convenient to determine the fatigue limit with periodic number NQ, but the prediction accuracy is not high, because the tool is affected by dynamic mechanical impact and thermal load which have a great influence on the fatigue fracture of tool material in the cutting process (simulation analysis as shown in Fig.5)[13].
Therefore, the foregoing model can be used for determining the tool life of various materials, and at the same time, both the creep resistance and strength property should be taken into account when selecting the tool materials.

Silicon Carbide Ceramic Turning Process Design and Parameter Analysis Zhenbo Wang1,a,Liang Zhang1,bandShuzhi Li1,c Mechanical Power and Engineering College Harbin University of Science and Technology Harbin,China awzb3328@163.com,bzlhkcx09@126.com,czjlsz123@126.com Keywords: Silicon carbide ceramic,Turning,Process design,Parameter analysis Abstract.This article mainly aims at the problem of silicon carbide ceramic mechanical turning difficult processing,by adopting the method of the numerical control turning processing.Design a special fixtures and a NC machining process to accomplish the manufacture of silicon carbide plate.And through the single factor analysis method to process parameters were analyzed.
Workpiece material properties and processing problems Functional ceramics,senior refractories,abrasives,metallurgical raw materials is the main application field of silicon carbide materials[2].Compared with the metal material,silicon carbide ceramic materials have very strong hard brittle, processing difficulties,using the method of common metal cutting is infeasible and the ceramics is not conductive,cannot adopt electric processing methods, such as electrical discharge machining,this greatly limits the use of silicon carbide materials, popularization and application of ceramic materials has been a corresponding block [3].
Fig.1 The location model of ceramic disc frock b.Tool design Silicon carbide ceramic is one of the most hard ceramic material hardness in all engineering ceramics,the difficulty of its processing is more than other materials,so reasonable design of tool is directly affects the precision grinding machining quality and efficiency.Figure 2 and figure 3 is used in the numerical control turning of the electroplated diamond grinding head and the real figure.
Experiment and analysis of parameters This test on grinding head size and spindle speed, feed speed three process parameters as a single factor level,surface machining of the ceramic plate,and measuring record its side damage.Diamond grinding wheel granularity were selected as the number 80,number: 150,number 300;Spindle speed were selected:26000r/min, 28000r/min,30000r/min;Feed speed respectively choice:0.1 mm/r, 0.15 mm/r,0.25 mm/r.
a.Effect of grinding head size on the side damage（unit:um）as shown in figure 4 (spindle speed of 28000 r/min,the feed rate is 0.1 mm/r): Fig. 4 The relationship of grinding head size and side damage quantity b.Effect of spindle speed on the side damage（unit:um）as shown in figure 5 (grinding head size is 150 mesh,the feed rate is 0.1 mm/r): Fig. 5 The relationship of spindle speed and side damage quantity c.Effect of feed rate on the side damage（unit:um）as shown in figure 6 (grinding head size is 150 mesh,spindle speed of 28000 r/min): Fig. 6 The relationship of feed speed and side damage quantity From the experiments we know grinding head size and side damage quantity is the related relationship, feed rate and side damage quantity is positively related to relationship, spindle speed and the amount of side damage is also present positive correlation, but relative to the other two factors, spindle speed affects the quantity of edge collapse is smaller.

Introduction Rolled magnesium alloy sheets are promising light-weight structural materials due to their excellent properties and large strength-to-weight ratio which are potentially suitable for applications in many industrial areas [1].
It has been documented that the microstructures, mechanical properties and texture evolution of Mg alloys are highly dependent on their primary deformation process, such as cross-rolling [4], different-speeds rolling [5], ECAP and ECAR [6].
It affects the mill set-up schedule, the thickness of the rolled metal, and the final product profile.
Rolling force is affected by many factors such as friction, metal properties and rolling deformation which show serious nonlinear relationship.
Chinese Journal of Mechanical Engineering.

Pollution can change the physical properties of soil, further affect the unconfined compression strength of cemented soil and induce instability or disruption of buildings.
Therefore, studying the effect of pollution on the engineering and mechanical properties of cemented soil has become more and more important, which made it a new topic in the area of environmental geotechnical engineering.
Dong et al. (2007) studied the electrical property of cemented soil eroded by sulphuric acid solution.
Experimental Study on Mechanical Property of Cemented Soil under Environmental Contaminations[J].
Study on electrical resistivity property of soil-cement polluted by NaOH[J].

Efforts have been done to improve the mechanical properties of scaffolds.
The effects of the microwave sintering conditions on the phase composition, microstructure and mechanical properties of the fabricated scaffold were investigated.
It shows that grain size is another important factor affects the strength of scaffold besides densification.
Generally, the strength of scaffolds is mainly determined by two factors, the properties of materials used and the structure style including macro-pores and defects, micro-structures and its distribution.
The mechanism of microwave sintering to improve mechanical properties of sintered bodies is complicated.

In order to estimate the thermal-shock influence on the mechanical properties, tensile tests of the conditioned samples were carried out at 1 mm/min loading rate.
To accomplish better mechanical properties of the GFRP composites, proper scattering of nano-particles in polymer region was becomes vital.
Ray, Water absorption behavior, mechanical and thermal properties of nano TiO2 enhanced glass fiber reinforced polymer composites, Compos.
Ray, Evaluation of mechanical properties of Al2O3 and TiO2 nano filled enhanced glass fiber reinforced polymer composites, J.
Eisenberg, Dynamic Mechanical Study of the Factors Affecting the Two Glass Transition Behavior of Filled Polymers.

This paper studied the effects of adding compatibilizer and alkaline treatment on the forming accuracy and mechanical property of WPC.
The factors affecting the interface adhesion strength are mainly: A whether the chemical bonds form in the interface.
Test tensile properties according to GB / T 1042-1922; test Charpy impact strength according to GB/T 1643-1993.
But their properties determine that the chemical bonds can't form between the interfaces.
Conclusions PP-g-MAH is good for the compatibilization of PP and wood flour, it can make the chemical bonds form to improve the mechanical properties.

Introduction Composite materials are sensitive to changes in the environment and their mechanical properties may vary considerably with environmental conditions.
Table 1 shows the properties of jute fiber and PLA sheet.
To investigate the effects of thermal and freezing cyclic environment on the mechanical properties of green composites, the specimens were heated at 60 in the oven, and frozen at -20 in a freezer.
It is reported that amorphous cellulose in natural fiber form hydrogen bonding at 60 [6], and differences in the thermal expansion of cellulose, hemicellulose, and lignin can cause nonreversible damage and voids that can affect the physical properties of natural fiber [7].
Fig.3 SEM photograph of green composites after thermal cycle (9 cycles) Fig.4 Surface morphology of composites from the freezing after water absorption Conclusions One of the most important factors in the using of materials is the durability about extreme environment.

The crystallization properties, thermal stability, flame retardant properties, mechanical properties and mechanism of flame retardant PET and fibers were studied.
The degree of orientation and crystalline are the important factors on the strength of the fiber.
The orientation factors increase slightly with the addition of the flame retardant increase.
This work describes a straightforward and systematic approach to prepare flame retardant PET fibers with superior mechanical properties.
Structure and properties of phosphorus flame retardant copolymer.

The sandwich piezoelectric ultrasonic transducer is used in machining, aerospace, national defense, biomedicine, electronic equipment, etc. area with its excellent acoustic properties and physical characteristics of ultrasonic.
The chips belong to high-power emission, with good piezoelectric properties, stronger field of low dielectric loss and high mechanical strength and have good stability of the electrical parameters.
There are many factors affecting the bandwidth, one of those is the radiation diameter of the front end of the transducer, the size of the front end of radiation is larger, the more bandwidth.
Accordingly, the whole mechanical quality factor of the acoustic system in ultrasonic machining can achieve more than 1500.
But not the mechanical quality factor of transducer as high as possible, many factors must take into account at the same time.