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Strain Measurement in the Steel Shell Surface Impacted by a Falling Ball Wei Liu1,a, Jie Song1,a, Hua Guan1,a, Xiao Han1,a, Jianzhong Wu2,b, Wenge Yang2,b , Xiaopan Li2,b 1College of Mechanical Engineering, Hohai University, Changzhou213022, Jiangsu China 2Xi'an aero-engine Co.LTD, Xi'an710021, Shanxi, China alwlnx101@163.com, bsongjiesophia1018@163.com Keywords: Shell; Strain Measurement; Impact Test; Falling Ball; LS-DYNA; Transient Simulation Abstract.
Liu [1] proposed a strain gauge in the impact test and found the biggest factor that affecting test strain change.
The paper built shell model with ANSYS/LS-DYNA software and simulated the impact test, and compared test data with simulation data, the conclusions are as follows: 1) In simulation, the friction and the damping factor were not considered.
The maximum simulation error compared with the impact test is 9.5% at the maximum strain amplitude. 2) There is an error between simulation data and test data in frequency distribution, the reason is that the constraint form of test equipment and material properties are quite different than that of the calculation models, it is needed to conduct further study. 3) Many high frequency harmonic waves were superimposed in the experimental data.
Marangoni: Mechanical Measurement.

Study on interface structure and in situ formation Mechanism in laser surface ceramic process Wei Li School of Mechanical Engineering, Shandong Jiao’tong University, Ji’nan 250023, P.
So it’s important to improve the surface properties of titanium alloy by surface treatment to extend their applications.
In material design, the service property of the layer should be considered as well as the property matching between the matrix and ceramic phases, the size and composition of ceramic phases, interface bonding between the coating and matrix, etc. to develop the best property combination of composite components and produce excellent compound layer[1].
The growth pattern of TiC was affected by the autologous growth mechanisam and outer conditions such as laser technical parameters and cooling speed, thus there were larger difference in the morphological character and dimension of dentrites.
Besides, property advantages of different ceramic phases were developed and the harmful factors of single ceramic phase strengthening was restricted, which apparently improved the property of laser alloyed coatings.

MATERIALS AND EXPERIMENTAL PROCEDURE 2.1 Materials and tensile properties In the present study, DP600 steel with a thickness of 0.9, 1.3, 1.6 and 1.8 mm and a width of 25, 50, 75 and 100 mm was used.
The chemical composition and initial mechanical properties of the DP600 steel are shown in Table 1 and Table 2 respectively.
Therefore in this study, the initial mechanical properties of the material were determined by performing the tensile tests on Shimadzu Autograph 100kN testing machine with the data acquisition maintained by a digital interface board utilizing a specialized computer program. 5, 25, 125, and 500 mm/min deformation speeds were performed.
Table 1: Chemical composition of DP600 steel (wt. %) Material C Mn P S Si Al DP600 0,092 1,912 0,014 0,003 0,147 0,031 Table 2: Mechanical properties of DP600 at various deformation speeds Mechanical properties Deformation speed(mm/min) 5 25 125 500 Yield strength(YS) (MPa) 377.09 397.098 401.90 417 Ultimate tensile strength (UTS) (MPa) 777.22 777.74 780.96 784.48 Uniform elongation (UE) (%) (mm/mm) 20.66 19.56 20.26 18.37 Total elongation (TE) (%) (mm/mm) 22.4 21.6 22 19 Strain hardening coefficient (n) 0,206 0,203 0,201 0,174 Strength coefficient (K) (MPa) 1102 1109 1101 1072 As shown in the figure the flow stresses and total elongations of the material were not changed significantly with increasing deformation speed except for 500mm/min deformation speed.
However the deformation speed did not affect the bending forces significantly.

According to Yang and Liu [2] even though titanium alloy is difficult to machine due to its low thermal conductivity and high chemical reactivity properties, manufacturers still opt for it for its superior properties.
Workpiece Material Constitutive Equations Hooke’s Law describe the elastic properties of materials.
Mechanical and thermal properties are required for both workpiece and cutting tool.
The reason titanium alloys are harder to machine is due to its inherent properties.
High temperature is the main factor of causing tool wear rapidly.

Next to granules’ performance both of these properties can be directly influenced by 3D printing process parameters.
Some properties such as surface area, particle size distribution or primary particle size directly affect the flowability and processability of the powders.
The porosity, the surface area, and homogeneity of the granules are important factors to be characterized, since they determine the amount of binder required during the printing process.
Results of the flow properties of the granules as well as the green properties of the printed scaffolds are presented in table 2.
Various properties of the scaffolds before and after heat treatment at 800°C for 1h.

As we all know, the microstructure is affected by many factors, such as deformation temperature, strain rate and et al.
Zhao, Microstructure and mechanical properties of AZ91D magnesium alloy prepared by compound extrusion, Mater.
Meng, Microstructure evolution and mechanical properties of Mg-11Gd-4.5Y-1Nd-1.5Zn-0.5Zr alloy prepared via pre-ageing and hot extrusion, Mater.
Umakoshi, Effect of long-period stacking ordered phase on mechanical properties of Mg97Zn1Y2 extruded alloy, Acta Mater. 58, 6282-6293 (2010)
Zhang, Microstructure, texture evolution and mechanical properties of multi-directional forged Mg-13Gd-4Y-2Zn-0.5Zr alloy under decreasing temperature, J.

The simulated results show that NC Cu can accommodate large plastic strains without cracking or creating damage in the grain interior or grain boundaries, revealing their intrinsic ductile properties compared with NC Ni.
While the plastic properties of NC metals have received considerable attention, there is not yet a complete understanding of the mechanisms of plastic behavior.
Therefore, the details of structure of GBs may have great influences on their mechanical properties.
These observations lead us to conclude that even for the FCC structures other factors should be taken into consideration in terms of their mechanical response under extreme cases.
The bonding nature of "defect" atoms at GB region from more fundamental level, such as ab initio calculation of GB structure and properties should play an important role in achieving this purpose.

High-heeled shoes also have shown to affect gait, particularly at the ankle joint, which is excessively plantar flexed.
Statistical techniques describe the fractal and time evolutionary properties of the COP, and infer additional information about the nature of the postural control system [5, 6] Localized muscle fatigue can be quantified by following the shift in the EMG spectral density towards lower frequencies, using MF of the power spectrum as a guiding parameter [2].
And we also investigated how the high-heeled posture affects on muscle fatigue.
These subjects had no history or evidence of uncorrected neurological or musculoskeletal problems that would adversely affect postural control.
EMG signals were pre-amplified by factors in the range of 1000-4000 (depending on the subject) and captured by a 12-bit A/D board (PLC 818, Scientific Solution Lab, USA) at a sampling rate of 1 kHz.

Introduction The properties of materials are generally dependent on the material type and composition.
With taking the advantages of great high-temperature drying efficiency of microwave and uniformed temperature distribution of oven, a microwave-oven intelligent control system was designed for hybrid heat treatment, which contains the following factors: (1)putting the wet materials into work warehouse; (2)starting microwave heat treatment program for drying raw materials; (3)changing the program to remove water vapor while the humidity in the warehouse above a certain value or switching to constant temperature air blast (oven mode) heat treatment while the humidity in the warehouse below the set value; (4)detecting the produced gas concentration and completing the heat treatment process when the gas concentration reaches the set value.
The IRTP-300L temperature sensor has the detecting temperature range of -20 ~ 300 oC, response time of 150 ms, and distance coefficient of 8:1 and it is also not affected by environment such as contamination, moisture, and electromagnetic interference [4].
Humidity detection and program switching As one of important parameters for intelligent control of heat treatment, humidity of the environment can directly affect the proper program switching during the heat treatment process and accordingly can affect the quality of product and production efficiency.
Gas concentration detection and program automatic stop As the key parameters for the determination of the heat treatment degree, gas concentration directly affects the success or failure of the product.

Tensile Properties of the Laser Welded Dissimilar Joints.
The HT on 316L is essentially for the purpose of residual stress relief and does not have a considerable effect on the mechanical properties.
Mi­ crostructure and mechanical properties of laser welded 316l SLM parts.
Laser weld­ ing of selective laser melted ti6al4v: Microstructure and mechanical properties.
Effect of standard heat treatment on the microstructure and mechanical properties of selective laser melting manufactured inconel 718 superalloy.