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Creep Life Prediction of Waspaloy using the Initial Strain Parameter Technique Seon-Jin Kim 1, a, Yu-Sik Kong 1, b, Won-Taek Jung 1, c, Jong-Taek Yeom 2, d and Nho-Kwang Park2, e 1 School of Mechanical Engineering, Pukyong National University, Namgu, Busan 608-739, Korea 2 Dept. of Materials Processing, KIMM, Sangnam-dong, Changwon 641-010, Korea a sjkim@pknu.ac.kr, bkongys@pknu.ac.kr, cweld27@yahoo.co.kr, dyjt96@kmail.kimm.re.kr, e pnk@kmail.kimm.re.kr Keywords: Creep life prediction; Creep rupture time; Initial strain parameter technique (ISPT); Larson-miller parameter (LMP); Waspaloy.
Introduction When a material is exposed to high temperatures coupled with various mechanical and thermal loading, the deformation and damage due to static creep and dynamic creep are expected.
Thus, it causes repair, maintenance, property degradation, and life reduction.
Consequently, it was clarified that the initial strain affects the creep properties and can be very important criterion for predicting or conjecturing quantitatively some various creep properties such as creep stress, creep rupture time, and so on. 0.1 1 10 500 600 700 800 900 1000 2000 550°C 600°C 650°C 700°C Creep stress, σ (MPa) Initial strain, ε0 (%) 0.1 1 10 1 10 100 1000 550°C 600°C 650°C 700°C Rupture time, tr (h) Initial strain, ε0 (%) Fig. 1 Creep stress vs. initial strain Fig. 2 Rupture time vs. initial strain Creep Life Prediction by ISPT.
But, it is necessary to investigate the comparison through more experimental data in future. 100 101 10 2 103 500 600 700 800 900 1000 2000 550°C/Experimental 600°C/Experimental 650°C/Experimental 700°C/Experimental LMP/Calculated ISPT/Calculated Creep stress, σ (MPa) Creep life (Rupture time), tr (h) 100 101 10 2 103 500 600 700 800 900 1000 2000 101 10 2 103 101 102 103 Range of "Factor of 2" 550°C 600°C 650°C 700°C Experimental rupture time, tr (h) Calculated rupture time, tr (h) Fig. 3 Comparison by ISPT and the LMP Fig. 4 Comparison by ISPT data Summary The creep properties such as creep stress and rupture time had quantitative relationship with the initial strain.

Generally, deformation and annealing procedure is involved in the fabrication process of Al-Mn alloy, where the sequential processing of heating and reductions to control the microstructure greatly influences the evolution microstructure and mechanical properties of the material.
Alteration in the sequence or employed procedure in the processing is used to control the microstructure which in turn affects the properties of the material.
However, the second-phase particle of Al-Mn based alloy is important factors affecting recrystallization behavior.
The microstructures of all specimens were characterized by OM, FE-SEM and TEM in order to investigate the change in the microstructure under different mechanical and heating conditions.

Mathematical Model Various factors are the source of vibration during milling.
Improving the structural damping of small diameter end mills [3], passive linear shock absorbers embedded in the machine spindle [4], adjustable vibration absorbers installed on the cantilever plate [5], [6], additional mass elements that improve the dynamic properties of the workpiece [7], also help to reduce the vibration amplitude during milling.
Dynamic milling model: m – reduced mass of the system; c - generalized stiffness coefficient; k – generalized damping factor; F (t) - cutting force.
One of the parameters that determine the value of the vibration amplitude у (t) is the depth of cut a (Fig. 1), which is included in the expression for the angle φ of contact between the cutter and the workpiece and affects the parameters m, k1, k2 ... k7 in Eq (1).
J. of Mechanical Sciences. 194 (2021) 262-271

Test factors are test time, load level and curing condition.
This illustrates that the density of concrete reduces, stress corrosion has greater impact on the damage of the internal micro-structure than the macro mechanical strength of concrete.
a Zero load b 30% load c 60% load Fig. 5 Chloride ion content in different curing conditions Conclusion (1) Load level and curing condition are important factors that affect chloride ion penetration depth and content in concrete.
Weiss et al, The influence of accelerated curing on the properties used in the prediction of chloride ingress in concrete using a Nernst-Planck approach, Construction and Building Materials, 2014 66 752-759

Modern requirements suggest an increase in all listed properties, at the same time the design should be technological in the manufacture and use – with a small weight and overall dimensions [2].
In order to increase the physical and mechanical propert of the coating, It was decided the sputtering of the target in a nitrogen atmosphere.
Further increase in the thickness of the coating does not significantly affect the attenuation of the thermal neutron flux.
The TiB2 compound allows achieving the required boron concentration and increasing the physical and mechanical characteristics of the material surface.
Freire Jr., Titanium diboride thin films produced by dc-magnetron sputtering: Structural and mechanical properties.

Self-consolidating concrete (SCC) has recently drawn attention to the construction industry in hot weather countries, due to its high fresh and mechanical properties.
As a result of the extreme environmental factors, SCC may arrive to construction site with low fresh quality.
The SCC mixtures were mixed for 2 hours under hot weather conditions and the fresh and mechanical properties were measured and evaluated.
Dubey, Influence of superplasticizer dosages on fresh properties of self-consolidating concrete, Proceedings of the fifth north American conference on fresh properties of self-consolidating concrete, Chicago, Illinois, USA, May 12-15,2015
Diawara, Influence of combined transportation time and temperature on flow properties of self-consolidating concrete," ASCE Journal of materials in Civil Engineering, 2014

Flow of Finite Element Analysis of Metal Powder in Medal Injection Mold Runner Jie Jin 1, a, Xin Bai 2,b, Fangyin Ning3,c 1，2College of Mechanical & Electrical Engineering, Zhejiang University of Technology, Hangzhou 310014, China abluejinjie@126.com,bbaixin20091985@126.com,cfangyin1001@126.com Keywords: Metal Powder Injection Molding; Mold Runner; Die Filling; Finite Element Simulation Abstract: Based on the continuum theory, combined with the characteristics of metal injection molding, constructs assumptions and control equation in the die filling process of MIM.With the FLOTRAN hydro-analysis module of ANSYS software, the melt’s velocity ,temperature and pressure fields during injection molding were simulated and compared for different sizes of circular section runners,and discussed the influences between different diameter runners and injection pressure on the flow behavior of melt.
Because the runners size is usually slightly smaller than the main runner, and the cross section shape and size of runner directly affect the velocity and filling time.
Mathematical model of MIM melt flowing in the channels Basic assumptions and the continuum model In numerical simulation, any physical model could not consider all factors, which should be removed a number of unimportant factors, to simplify model.
Therefore, on different injection conditions, different physical properties of feedstock will inevitably require different injection pressures.

Introduction Unsaturated soil is widely distributed on the earth's surface, in considering the existence of negative pore water pressure in unsaturated soil, the mechanical properties have changed greatly relative to the saturated soil.
The rainfall calculating parameter of various rain types effect factor rain type rainfall intensity (mm/h) rainfall duration (h) rain capacity (mm) rainfall rainstorm 125 2 250 200 2 400 During the calculating, the left , right and bottom side of soil slope were presumed as imperviousboundaries,like Q=0,while the surface of slope was set as free infiltration border.if the rainfall intensity was smaller than the slope soil permeability,the specificrateofflow of slope surface was equal to rainfall intensity,and the specificrateofflow is: q=i*cosa
After analyzing from Fig.4 and Fig.5,these showed that after rainfall of which the rainfall intensity was 125mm/h or 200mm/h,the soil of slope surface achieved the saturated condition.When the pore water pressure of slope surface was 0,while the negative porewater pressure which was affected by rainfall corresponding reduce ,too.Between the initial underground water level and slope surface,it appeared unsaturated zone,and the area of which constantly Changed,especially in the toe of slope.Due to the function of rainfall infiltration ,the underground water table of slope had a certain degree of improvement after rainfall,in a certain rainfall time,the amplitude of underground water rise was affected by the rainfall intensity.Campared with Fig.4 and Fig.5,it showed that the underground water table of slope toe had a certain degree of improvement after raining for 2 hours,while the amplitude of underground water rise was larger,so it indicated that the amplitude of underground water rise
Comparatively analyzed fig.6 and fig.9 we know that the change trend of pore water pressure downward along the section was inconsistent after the rainfall continuing for 2 hours on the slope, fig.6 presented first reducing and then increasing but fig.9 was the trend of always increasing, which indicated that the size of the rainfall intensity would also affect the infiltration depth, under the condition of the rainfall time was same but the rainfall intensity was different, rainfall infiltration depth was proportional to the size of rainfall intensity.

Study of Powder Removing Technique for Film Laminating Yang Zhang 1, a, Jifei Cai 1,b , Kangle Zou1,c 1School of Information and Mechanical and Electrical Engineering, Beijing Institute of Graphic Communication, Beijing 102600 azhangyang@bigc.edu.cn, bcaijifei@bigc.edu.cn,c355037569@qq.com Keywords: Powder Removing; Film Laminating; Post-Printing Processing Abstract.
Especially for the pre-coated film laminating, the powder quality may directly affect the quality of film laminating.
This involves the powder properties.
The speed of paper is another factor that affects the powder sticking effect.
But in consideration of the case when the powder removing machine is used in combination with a film laminating machine, the speed of film laminating may be affected, so the powder removing speed should not be too slow.

FMLs have several advantages over monolithic materials, which include higher strength, fatigue resistance, impact resistance, fracture toughness, fire resistance and higher mechanical energy absorption [3].
Forming limit height of specimens with different factors Effect of Core Layer.
The direction of layup of core layer is also an important factor for sheet metal forming [8].
For different thickness of the skin layer, the interface situation will affect the optimal forming height
Jin, Influence of the morphology of alumina filler on electrical and thermal properties of epoxy resin composites.