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Introduction Cemented carbides, also known as hardmetals, are metal-matrix composite materials comprised of individual tungsten carbide grains imbedded in a ductile metal binder matrix of either cobalt or nickel, which lead to excellent mechanical properties, such as high hardness, high resistance, and good toughness[1,2].
However, the physical and mechanical properties of cemented carbides lead to high machining cost and low production efficiency.
YG8 is mainly used as insert tools and wear resistance parts, and its properties are listed in Table 1.
Table 1 Workpiece properties Material Chemical compositions Hardness [HRA] Young’s modulus [KN/mm2] Density [g/cm3] YG8 WC-8%Co 89 600 14.5 – 14.9 The experiment was conducted on high-speed grinder.
However, the unbalance of spindle monitored by SBS increased when grinding parameters are above a certain value, and is considered to be one of factors to affect surface quality, the further investigation is necessary.

Main Contents of Grinding Process Simulation As a complex physical process, grinding process is subject to a number of input factors and produces a variety of physical and mechanical phenomena.
Grinding wheel topography simulation is mainly modeled for specific structure and morphology of modeling of the grinding wheel surface, and implements the grinding simulation in order to analyze the grinding properties of the grinding wheel.
Grinding forces, grinding temperature and grinding vibration produced during grinding are the main factors affecting the grinding quality.
Grinding process simulation can predict the main affecting factors in the grinding process and the process results, and optimize the grinding parameters.
In the area of the simulation of workpiece surface topography, the simulation will be considered the abrasive wear, grinding heat, vibration machine, plastic deformation of the workpiece material and other comprehensive factors, in order to more accurately predict the workpiece processing quality and optimize the process parameters.

But grinding process is a complex process, a variety of physical and chemical factors are intertwined and the dosage of grinding aids should be strictly controlled.
It is necessary to study of the minerals crystal structure, dissemination size, form of occurrence, and mosaic relationship between diaspore and silicon minerals, and to establish the relations between bauxite process mineralogy properties and bauxite selective dissociation; (2) Study on mechanical properties and factors of bauxite crushing.
Exploration of relationship between grinding aids and crushing mode, and examination on the impact of aids on the surface properties and flotation separation characteristics of bauxite grinding production, are all worth researching.
(5) Study on the influence factors of selective grinding, such as the combination form of mill and classifier, the dissociation process as well as different types of grinding and classification equipment.
Grinding is a highly complex process, so there are many factors that affect the selective grinding of minerals, the impact of these factors on bauxite grinding behavior, and the law between them, are all worthwhile for researching.

With the increase of mining depth, increasing stress, coupled with complex geological structures, faults development, and water inflow increase, particularly high-stress become key factors induced pressure bump.
The number of coal mines affected by pressure bump will be increasing [3,4].
Impact orientation theory believed that impact orientation in coal seams is the inherent properties of coal and rock media and the internal factors of pressure bump.
In addition, the main reasons of pressure bump are mining depth, the geological structure and other natural factors.
Mining technology, support method and even the frequency and intensity of coal-gun become important motivating factors.

Compared with the horizontal axis wind turbine, they have better mechanical properties, simpler structures and lower costs.
According to the aerodynamic theory, thickness and camber as airfoil geometric parameters, and blade pitch angle can affect airfoil aerodynamic characteristics, and further affect the whole wind turbine performance.
(8) Velocity inducing factor ɑ is defined as
(11) Inducting factor ɑ can be calculated and get an approximate solution.
In addition, airfoil thickness changes will affect the distribution of fluid field and the surface pressure coefficient of aerofoil ,and then influence wind energy using ratio[7].

These methods are worthy to be considered to enhance the surface properties of titanium implant manufactured by EDM and have considerable economic savings.
Thus, for this criteria, excepting HCl acid etching, the methods carried out in this study are worth consideration to enhance the surface properties of titanium implant manufactured by EDM.
Feller et al. revealed that cellular adhesion, proliferation, and differentiation are influenced by the material properties of titanium implants, including their wettability [28].
The comparison of contact angles (A - original EDM before engineered; B - rotary polishing; C - ultrasonic cleaning; D - mechanical brushing; E - HCl-etching; F - H2SO4-etching) The two factors that most influence the wettability of material are surface morphology and chemical components [29].
Fang, Influence of multiple factors on the wettability and surface free energy of leaf surface, Applied Sciences 9 (2019) 593

Through-thickness microstructure, texture and mechanical property gradients in the longitudinal section of AA 7055 rolled plate have been investigated using electron back-scattered diffraction (EBSD) technique.
These good properties are attributed to the T77 temper [1-5].
However, the microstructure and texture, which significantly affect the mechanical properties, may be inhomogeneous through the thickness of the rolled sheets or plates due to the inhomogeneity of the deformation caused during rolling [6-8], and the non uniformity of the recrystallization that occurs during the heat treatment [9].
Therefore, considering "structure application", how to control the microstructure and texture during deformation and the sequent heat treatment in order to obtain good combined properties is imperative.
Therefore, the anisotropy of the strength is mainly affected by grain shape [12].

These elements contribute to improve the technological properties of the new filler alloy: melting, flowing, wetting and solidification.
It depends on the sizes of the sheets and the parameters of the flame: flow rates of acetylene and oxygen, power, temperature, type of flame (reducing, neutral, oxidizing), length, height over the brazing zone, tilt, as well as other factors.
The work temperature of the base metal is also an influence factor of the brazing time.
The properties of the new experimental and ecological filler alloy, regarding melting, flowing, wetting and solidification, have also been verified during the experiments.
The ecological properties of the new brass are adequate, as it exhales no lead, cadmium or other hazardous substances.

Factors influencing calcium phosphate deposition on three dimensional printed hydroxyapatite (3D printed HA) by biomimetic process including soaking times (2, 4 and 6 hrs), solution temperatures (23, 37 and 50 °C) and solution refreshment (refreshed and non-refreshed) were studied.
In this study, the factors influencing biomimetic deposition of calcium phosphate crystals on 3D printed HA including soaking times (2, 4 and 6 hrs), solution temperatures (23, 37 and 50 °C) and solution refreshment (refreshed and non-refreshed) on phase composition, deposition content and microstructure were investigated.
The differences in properties amongst samples were analyzed using an analysis of variance (ANOVA) and Tukey post hoc testing.
The refreshment of ACS solution was needed to maintain high rate of deposition especially at high temperature where the dissolution of 3D printed HA was pronounced without affecting the phase and microstructure compared to using non-refreshed solution.
Layrolle, Proteins incorporated into biomimetically prepared calcium phosphate coating module their mechanical strength and dissolution rate, Biomaterials, 24 (2003) 65-70

To make the simulation results more reliable, these important elements are also taken into account, such as temperature-dependent properties of material, the phenomenon of plasma channel radius expanding, the percentage of discharge energy transferred to the workpiece and Gaussian distribution of heat flux.
In this process, high temperature gradients are produced, which bring about thermal stresses in a small heat affected zone.
Fig. 1 Finite element geometric model Fig. 2 Flow chart for the computing procedure Table 1 Relevant material properties of steel Temperature(oC) 25 100 400 1000 1500 Thermal conductivity(J/s m K) 47.68 43.53 36.02 27.53 24.02 Specific heat(J/Kg K) 460 465 475 650 665 Elastic modulus(Pa) 2.05E11 1.95E11 1.80E11 0.70E11 0.40E11 Yield strength(Pa) 1.20E9 2.40E9 0.93E9 0.44E9 0.07E9 Thermal analysis.
The size of heat flux on the workpiece surface is an essential factor in the model of the micro-EDM process.
Some researchers considered the spark radius is time-dependent, while some considered the current pulse affects the spark radius.