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Study on 4Cr9Si2 Martensitic heat-resistant steel in CWR Jianghua Huang 1, a, Jinping Liu 1, Baoyu Wang 1, Zhenghuan Hu1 1School of Mechanical Engineering, University of Science and Technology Beijing, Beijing 10083, China ahjh79303416@126.com Keyword: 4Cr9Si2 Martensitic heat-resistant steel, CWR, FEM, thermal-mechanical coupling Abstract. 4Cr9Si2 Martensitic heat-resistant steel is inlet valve and the exhaust tappet materials.
Has high temperature resistance, corrosion resistance, wear-resistant properties. its high chromium content, Silicon content are reached 2%~3%, so its rate of work hardening is larger, alloy content over 10%, so it is a more difficult forming high alloy steels. 4Cr9Si2 after quenching and tempering, with strong strength and toughness, high harden ability of it, 4Cr9Si2 are generally used for manufacturing automobile engine intake valve and exhaust valve Rod [1].
(a) (b) (c) Fig.2 Forming process of the rolled piece: (a) knifing zone; (b) sketching zone; (c) sizing zone Analysis of the central porosity Cross-Wedge Rolling is a plastic forming technology of high efficiency, low consumption, but, because of its central porosity, surface spiral and necking had affected the scope of its usage.
Fig.3 Work piece with a central porosity Fig.4 Location of point tracking in the billet This article uses widely Cockcroft and Latham’s damage factor to study central defects in Deform-3D, the expressions as below [7]: (4) —— maximum stress； —— equivalent stress； —— equivalent strain； C —— material parameter.
[4] Fengshan Du, Xuetong Li, WANG Minting, 3D coupled thermo-mechanical nonlinear FEM simulation of cross wedge rolling [J], Chinese Journal of Mechanical Engineering, 2002 [5] Jin Zhou, Zhejiang Han, Baicheng Liu, et al.

Especially, pore size and distribution on scaffolds has been observed to significantly affect cell adhesion, migration, and proliferation in vitro and influence the rate and depth of cellular in-growth in vitro and in vivo [2].
Due to its outstanding properties in terms of biocompatibility, biodegradability, non-antigenicity and chelating ability, AL has been widely used in a variety of tissue engineering [4].
Also, Hollister presented that the design of pore structures were critical factor in the scaffolds and the pore structures determined the cellular behaviors in vitro and in vivo conditions [2].
Kim, Inter-connecting pores of chitosan scaffold with basic fibroblast growth factor modulate biological activity on human mesenchymal stem cells, Carbohyd.
Structure, gelation rate and mechanical properties, Biomaterials. 22 (2001) 511-521

The sampling area and extraction method also have an effect on the physical and mechanical properties of plant fibers [7].
They were also used to produce polyester resin-based composites with good physical and mechanical properties.
Physical and mechanical properties of raw and processed NaOH (2% ,5%) fibers and comparison with other natural fibers.
Many factors can explain this difference, such as weather conditions, plant age, storage conditions, and location of the fiber in the plant [21]. 3.2.4 Mechanical properties The Table 1 and figure 5 presents the mechanical properties (tensile strength, and Young’s modulus) of GB fibers obtained by extraction of NaOH 2% ,5% and biological retting. it is found that the extraction process that produces overall fibers of best mechanical characteristics is the extraction by NaOH2%.
This behavior would be due to the fact that the 2% NaOH extraction positively affected the properties of the fibers compared to other methods.

These changes depend upon physical and chemical properties of powder material.
Mechanochemical processing of powders is a very energy-consuming procedure with low efficiency factor.
In the mechanically processed material, the rate of energy entry affected only the mass fraction of particles larger in size than 90 μm.
Ghaffari, The effect of milling speed on the structural properties of mechanically alloyed Fe–45%Ni powders, J.
Delaey, Structure and properties of Cu, Ni and Fe powders milled in a planetary ball mill, Scr.

FRP is light in weight, high modulus, specific strength [1], high damping, low thermal expansion and good dimensional stability [2;3] which make it is suitable to be used in various applications of mechanical engineering such as automobile, biomechanics and aerospace [4].
Therefore, the manufacturing cost of CFRPs’ parts need to be minimized, the factors that influenced the end product’s surface quality such as cost of severe tool wear, which shortens the tool life, fibre pull-out and delamination of CFRP need to be eliminated.
FRP’s composites contain two phases of materials with drastically distinguished mechanical and thermal properties.
Table 1 Physical Properties of CFRP Tool material Solid uncoated carbide Work material Carbon fibre reinforced plastic Cutting speed (m/min) 160, 165 and 194 Feed rate (mm/tooth) 0.14 and 0.225 Depth of Cut (mm) 0.55 and 0.91 Result and Discussion Tool Wear Mechanism In machining of CFRP, tool wear is one of important aspect.
(a) V= 165, F= 0.14, D0.55 (b) V= 165, F= 0.225, D0.91 (c) V= 194, F= 0.14, D0.91 Fig. 4 Distance travelled at different cutting parameter Conclusion Severe tool zone affects the tool performance as it reduces the tool life at higher cutting parameter.

Hybrid Non Conventional Machining of Glass - A Review Nagaraj Y.1,a*, Jagannatha N.2,b and Sathisha N.3,c 1Research Scholar, Department of Mechanical Engineering, SJMIT, Chitradurga, Karnataka, India 2Professor, Department of Mechanical Engineering, SJMIT, Chitradurga, Karnataka, India 3Professor, Department of Mechanical Engineering, YIT, Moodabidri, Mangalore Karnataka, India anyk6426@gmail.com, bjagan_nath05@rediffmail.com csathishan20@rediffmail.com Keywords: non conventional machining, material removal rate, heat affected zone, surface finish, tool wear Abstract.
Advance machining techniques are developed to fabricate hard to machine materials with excellent material properties.Traditional machining of such materials creates high cutting forces that, in some cases may not be maintained by the workpiece.
Jagannatha et al. [15] performed the machining on glass by combining abrasives with hot air jet to study the material removal rate and surface roughness using one factor at a time approach.
Decrease in the mechanical strength and increase in the machinability was observed.
The mechanical properties at the interface was approximately same as that of base materials.

Introduction As final drive is an important part of automotive transmission, its quality will directly affect the overall performance of the car[1].
And then mechanical surface vibration is the language of mechanical faults[2].
This method is more and more widely used in faults diagnosis field and it has real-time property, high accuracy and high reliability.
The various factors can lead to gear faults including the errors of gear manufacturing and assembly, poor lubrication, the stiffness variation of gear meshing, deformation of gear and gear damage.
(4) The vibrational components below the meshing order are greatly affected by the vibration of test bench, especially in the 1st order and 2nd order.

Instruction Reinforced concrete consists of two materials with different physical and mechanical property.
However, given the many factors that could affect the bond, to establish a reasonable theoretical model is still some way off.
As we all know, concrete is a material with disparate mechanical property to stretch or compression.
The disparate property will definitely affect the bond-slip characteristic of the structure bearing alternating load.
Xu: Test study of properties of reinforced-concrete bonded anchor [PhD] 1990, (Tsinghua University), in Chinese

To solve these problems, several authors have studied the influences of some experimental factors such as temperature and of mineral and organic additives on the workability and the setting properties of cements.
As a result, citric acid improves the setting times and mechanical properties of α-TCP bone cements.
Thereafter, we investigated the effect of citric acid concentration on mechanical properties and injectability, and developed a calcium phosphate cement with improved mechanical properties and injectability as a bone substitute.
Particle size is important for bone cement because it affects the properties of the dough stage, i.e., its viscosity and flow.
Results indicated that the concentration of citric acid in the liquid component influences both the mechanical properties and injectabilities of cements.

In the present study, MSP was used to investigate the effects of the peening conditions on the surface properties and fatigue properties of austenitic stainless steels.
The stress concentration factor is 1.04.
The effects of surface properties on fatigue strength are discussed.
Summary MSP was used to investigate the effects of the peening conditions on the surface properties and fatigue properties of austenitic stainless steels.
In addition, the fatigue properties were improved by the use of ordinary media.