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To meet those requirements, the thermal error can be a major concern affecting machining precision of machine tools [1].
Substantial efforts have been devoted to better understand the thermo-mechanical behavior of a high-speed ball screw feed drive system.
Given the assumption of a linear elastic response, the stress-strain relationship is given by, where D has the form (9) , (10) (11) D is the elasticity matrix consisting of the material properties, whereas the properties of E, ν and α are the Young’s modulus, the Poisson’s ratio and the coefficient of thermal expansion (CTE).
The average cell length was around 0.0011m with the least spacing of 0.00045m to resolve the rapid variations of thermal properties.
Shin, “Integrated dynamic thermo-mechanical modeling of high speed spindles, part I : model development,” transaction of the ASME, J.

With the advantage of high specific strength, excellent design-ability, anti-fatigue performance, good corrosion resistance, special electromagnetic properties, CFRP laminate is widely used in the field of aerospace and aviation [1].
The influence factors of CFRP laminate drilling-induced defects at the hole exit are studied.
On the contrary, the broken-edge factor Ld for grit size 40/45 is much less to the broken-edge factor Ld for grit size 25/30 and no tear occurs at the hole exit for grit size 40/45.
Table 2 shows the effect of feed speed on expanding factor Da.
It is the improving of cutting ability of core drill that ensures the decrease of cutting heat, so the heat affected zones of CFRP laminate become small and the thermal deformation decreases [6], which make the diameter at the hole exit get close to the diameter of brazed diamond core drill.

Contaminants, either in the original titanium powder, from the binder, or from the sinter furnace atmosphere, are usually a big concern for the component designers because these impurities significantly affect the mechanical properties of the final products [5].
Secondly, since most engineering plastics have a wide range of decomposition temperatures up to 500 °C [17], the polymer must be carefully chosen by the factors such as polymer structures, molecular weights, crystallinity and impurities.
As an example, Tijet, a German company, is using a wax-based binder system, which contains 32vol% mixture of PE, PW and SA [23] to produce engineering components such as bone screws for medical implants from Ti-6Al-4V and Ti-6Al-7Nb with mechanical properties equivalent to those of wrought alloys.
In spite of the success of PEG binder, one report discouraged the use of PEG because PEG results in increased oxygen content in the sintered parts due to the incomplete removal and hence adversely affects mechanical properties [26].
Takaki, Effects of pores and oxygen content on mechanical properties of a sintered Ti-4 mass% Cr alloy, Journal of the Japan Society of Powder & Powder Metallurgy 42 (1995) 911-917

In the manufacturing procedure, there are many factors impact the products quality, such as raw materials, methods, man, measure and environment.
Detection for remanufacturing core mainly are geometric accuracy testing, surface quality inspection, physical and chemical properties testing, potential defects (internal cracks, etc.) detection, surface materials and the substrate bond strength and so on.
The difficulty for remanufacturing quality control is how to use the limited quality information before to guide the future production. quality characteristics Indexes obey a normal distributionN(μ, σ2) [[]Jing Sun: Close to Zero Rejects Process Quality Control Tsinghua University Press (2001) (In Chinese) —[]Chunyu Liang: Mach (1998) 168~172 []Sihua Qi, Yetai Fei and Jian Sun: China Mechanical Engineering 12 (2001) 223~225 []Keli Ma: China Mechanical Engineering 10 (1999) 621~622 ] and parameter μ and parameter σ2 are forming a prior distribution.
The control lines are as follows: (12) Certification for remanufacturing products Products quality is not only concern to the process, but also have a link with other factors and it is not only depend on statistical quality management that can be solved commendably.
conclusion There may be a lot of factors that affect the remanufacturing products quality, but detecting the cores is particular important.

Accordingly, although dynamic recovery occurred in the ODS steel, it had not affected the creep deformation rate.
Oxide dispersion strengthened (ODS) steels are promising candidate for high temperature materials of a nuclear fusion reactor because of excellent mechanical properties.
Although ferritic ODS steels are excellent in creep properties compared with martensitic ODS steels, the anisotropy of the mechanical properties in correlation with rolling or extrusion is large.
However, since the decrease in dislocation density is the main factor of dynamic recovery in usual martensitic heat resistant steel, detailed analysis of the dislocation density during creep deformation is required.
Consequently, dynamic recovery did not affect the creep deformation rate, though it did occur during creep test.

There are many factors affect the RC cracking, including member geometry, loading, variability in concrete properties, volumetric changes in the concrete, amount and distribution of the reinforcement, and bonding between the concrete and reinforcement [1].
All these factors make it complicated to predict the crack location and direction and they are also of primary importance for the accurate description of the physical behaviors of RC structures.
The detailed descriptions about the Weilbull distribution of material properties and constitutive law of MFPA 2D have been given in [13].
The reinforcement and concrete are partitioned into a set of elements with same size and different mechanical characteristics in order to reflect the heterogeneous mechanical properties in the material.
The material properties for the concrete and steel reinforcement are adopted from experimental data [8, 11], and the bond interfacial properties described in the previous section.

In these parameters, Marangoni force is the most important in affecting the molten metal flow and the contour of the melt pool.
Introduction A Laser cladding technology has revealed as a multi-purpose tool with numerous applications in surface engineering, such as repairing damaged molds used in enhancing service life in marine engine valves and turbine blades [1], improving wear behavior [2] or mechanical and electrochemical properties of mild steel [3], and so on.
The thermo-physical properties of ZM5 were allowed to vary with temperature and phase state of the material during the simulation.
Effect of Marangoni force On the surface of the melt pool, there exists gradient of surface tension due to large temperature gradient. as one factor of driving fluid flow, this gradient of surface tension may affect the flow pattern of molten metal in melt pool.

Applied test load has been found to be the most significant factor affecting the wear rate [22].
Previous studies focused mainly on increasing the tensile and wear properties of the FGM outer zone.
Evaluation of Wear Properties.
Interaction of Parameters Affecting Wear.
Varol, “Microstructural characterization and mechanical properties of functionally graded Al2024/SiC composites prepared by powder metallurgy techniques,” Trans.

The utilization of fly ashes produced by circulated fluidized bed combustion (CFBC) has been limited in construction application due to their inherent high sulfate and carbon contents although CFBC fly ash exhibits very good binding properties without requiring any supplementary activator.
For example, Diaz-Loya et al. reported that the mechanical behavior of FFA-based GPC is similar to that of ordinary Portland cement concrete [4].
Because of these abnormal chemical and physical characteristics, the use of CFBC fly ash in construction applications as concrete material has been limited although CFBC fly ash exhibits very good binding properties without requiring any supplementary activator.
Shon et al. [7] reported that the determination of activation energy for ASR is capable of providing direct accountability for a variety of important material-related factors that affect ASR behavior of mortar/concrete such as temperature, alkalinity, aggregate reactivity, humidity, and age.
Vaidya: Mechanical properties of fly-ash based geopolymer concrete.

Conductive Polymer Composites from Polylactic Acid / Natural Rubber Filled with Carbon Black Yose Fachmi Buys1,a, Nor Afiza Syafina Lokman1,b 1Department of Manufacturing and Materials, International Islamic University Malaysia, Jalan Gombak 53100, Kuala Lumpur, Malaysia ayose@iium.edu.my, bafizasyafina@gmail.com Keywords: Conductive Polymer Composites, Polylactic Acid, Natural Rubber, Carbon Black, Electrical properties Abstract: In order to develop environmentally friendly conductive polymer composites, polylactic acid (PLA) was melt blended with natural rubber (NR), with addition of carbon black (CB) as the conductive filler.
This research aims to fabricate CPC from biodegradable PLA matrix based with improved toughness property.
Dynamic Mechanical Analysis (DMA) Measurement.
Information on morphology of matrix consist of polymer blend is a matter of importance in determining the dispersion states of CB, which in turn will affect the electrical properties of CPC.
The continuity of CB network as well as continuity of the phase with rich filler content are important factors that lead to high electrical conductivity [7].