scholarly journals A Proposed Method to Assess the Mechanical Properties of Treadmill Surfaces

Sensors ◽  
2020 ◽  
Vol 20 (9) ◽  
pp. 2724
Author(s):  
Enrique Colino ◽  
Jorge Garcia-Unanue ◽  
Bas Van Hooren ◽  
Leonor Gallardo ◽  
Kenneth Meijer ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Reliable Method ◽  
Longitudinal Axis ◽  
Test Method ◽  
Vertical Deformation ◽  
Sensitive Test ◽  
Absolute Minimum ◽  
Measuring Device ◽  
Support Area ◽  
The One

The aim of this study was to define a reliable and sensitive test method for assessing Shock Absorption (SA), Vertical Deformation (VD), and Energy Restitution (ER) in treadmill surfaces. A total of 42 treadmills belonging to four different models were included in the study: (a) Technogym Jog700 Excite (n = 10), (b) Technogym Artis Run (n = 12), (c) LifeFitness Integrity Series 97T (n = 11), and (d) LifeFitness Integrity Series DX (n = 9). An advanced artificial athlete (AAA) device was used to assess SA, VD, and ER at three different locations along the longitudinal axis of each treadmill and in the support area of the athletes’ feet. For each location, our results show that the error assumed when performing one impact with the AAA instead of three (SA ≤ |0.1|%, VD ≤ |0.0| mm, and ER ≤ |0.2|%) is lower than the smallest changes that can be detected by the measuring device (SA = 0.4%, VD = 0.2 mm, and ER = 0.9%). Also, our results show the ability of the test method to detect meaningful differences between locations once the one-impact criterium is adopted, since absolute minimum differences between zones (SA: |0.6|%, VD: |0.3| mm, and ER: |1.2|%) were above the uncertainty of the measuring device. Therefore, performing a single impact with the AAA in each of the three locations described in this study can be considered a representative and reliable method for assessing SA, VD, and ER in treadmill surfaces.

scholarly journals Development of optical, microstructural and mechanical properties of porcelain stonewares

2021 ◽  
Vol 53 (1) ◽  
pp. 79-90
Author(s):  
Tuna Aydin ◽  
Osman Bican ◽  
Recep Gümrük ◽  
Hamdi Kuleyin
Keyword(s):  
Mechanical Properties ◽  
Wear Resistance ◽  
Production Systems ◽  
Wear Test ◽  
Test Methods ◽  
Test Method ◽  
New Production ◽  
Aesthetic Appearance ◽  
Optical And Mechanical Properties ◽  
The One

New production systems developed in recent years made it possible to improve different aesthetic appearance and large sizes for porcelain stonewares. In order to produce these tiles, optical and mechanical properties of the porcelain stonewares should be improved. Optical and mechanical properties also related with microstructure. In this study, spodumene, alumina and zircon were used to improve the microstructure of the porcelain stonewares and consequently their optical and mechanical properties. The wear resistance of porcelain stonewares is the one of the most important mechanical properties. In this study, a different test method was used because the existing wear test methods on the tiles were insufficient. The solid particle impingement method using alumina particles was used to determine wear resistance of the porcelain stoneware bodies.

scholarly journals The Influence of Different Plasma Cell Discharges on the Performance Quality of Surgical Gown Samples

Materials ◽  
2021 ◽  
Vol 14 (15) ◽  
pp. 4329
Author(s):  
Atif H. Asghar ◽  
Ahmed Rida Galaly
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Exposure Time ◽  
Electrical Characteristics ◽  
Cathode Fall ◽  
Treatment Efficiency ◽  
Performance Quality ◽  
Surgical Gown ◽  
The One

An experimental study was performed on a low-density plasma discharge using two different configurations of the plasma cell cathode, namely, the one mesh system electrodes (OMSE) and the one mesh and three system electrodes (OMTSE), to determine the electrical characteristics of the plasma such as current–voltage characteristics, breakdown voltage (VB), Paschen curves, current density (J), cathode fall thickness (dc), and electron density of the treated sample. The influence of the electrical characteristics of the plasma fluid in the cathode fall region for different cathode configuration cells (OMSE and OMTSE) on the performance quality of a surgical gown was studied to determine surface modification, treatment efficiency, exposure time, wettability property, and mechanical properties. Over a very short exposure time, the treatment efficiency for the surgical gown surface of plasma over the mesh cathode at a distance equivalent to the cathode fall distance dc values of the OMTSE and for OMSE reached a maximum. The wettability property decreased from 90 to 40% for OMTSE over a 180 s exposure time and decreased from 90 to 10% for OMSE over a 160 s exposure time. The mechanisms of each stage of surgical gown treatment by plasma are described. In this study, the mechanical properties of the untreated and treated surgical gown samples such as the tensile strength and elongation percentage, ultimate tensile strength, yield strength, strain hardening, resilience, toughness, and fracture (breaking) point were studied. Plasma had a more positive effect on the mechanical properties of the OMSE reactor than those of the OMTSE reactor.

scholarly journals Insights into Mechanical Properties of the 1980 Irpinia Fault System from the Analysis of a Seismic Sequence

Geosciences ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 28
Author(s):  
Gaetano Festa ◽  
Guido Maria Adinolfi ◽  
Alessandro Caruso ◽  
Simona Colombelli ◽  
Grazia De Landro ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Early Warning Systems ◽  
Fault System ◽  
Minimum Size ◽  
Double Difference ◽  
Warning Systems ◽  
Initiation Mechanism ◽  
Earthquake Early Warning Systems ◽  
The One

Seismic sequences are a powerful tool to locally infer geometrical and mechanical properties of faults and fault systems. In this study, we provided detailed location and characterization of events of the 3–7 July 2020 Irpinia sequence (southern Italy) that occurred at the northern tip of the main segment that ruptured during the 1980 Irpinia earthquake. Using an autocorrelation technique, we detected more than 340 events within the sequence, with local magnitude ranging between −0.5 and 3.0. We thus provided double difference locations, source parameter estimation, and focal mechanisms determination for the largest quality events. We found that the sequence ruptured an asperity with a size of about 800 m, along a fault structure having a strike compatible with the one of the main segments of the 1980 Irpinia earthquake, and a dip of 50–55° at depth of 10.5–12 km and 60–65° at shallower depths (7.5–9 km). Low stress drop release (average of 0.64 MPa) indicates a fluid-driven initiation mechanism of the sequence. We also evaluated the performance of the earthquake early warning systems running in real-time during the sequence, retrieving a minimum size for the blind zone in the area of about 15 km.

scholarly journals Application of the plasticity characteristic determined by the indentation technique for evaluation of mechanical properties of coatings: I. specific features of the test method procedure

2004 ◽  
Vol 36 (1) ◽  
pp. 27-41 ◽  
Author(s):  
A.V. Byakova ◽  
Yu.V. Milman ◽  
A.A. Vlasov
Keyword(s):  
Mechanical Properties ◽  
Indentation Load ◽  
Test Method ◽  
Simplified Model ◽  
Micro Hardness ◽  
Properties Of Coatings ◽  
Modified Model ◽  
Plasticity Characteristic ◽  
Measurement Results ◽  
Hardness Values

Specific features of the test method procedure capable for determining the plasticity characteristic dH by indentation of inhomogeneous coatings affected by residual stress was clarified. When the value of the plasticity characteristic for coating was found to be as great as dH > 0.5 a simplified model was found to be reasonably adequate, while a modified model assumed compressibility of the deformation core beneath indentation. The advantage of the modified approach compared to the simplified one was grounded experimentally only if the elastic deformation for coating becomes greater than ?e ? 3.5%, resulting in the decrease of plasticity characteristic dH < 0.5. To overcome non accuracy caused by the effect of the scale factor on measurement results a comparison of different coatings was suggested using stabilized values of the plasticity characteristic dH determined under loads higher than critical, P ? Pc, ensuring week dependence of micro hardness values on the indentation load.

A novel test method for mechanical properties of characteristic zones of girth welds

2021 ◽  
pp. 104533
Author(s):  
Hailiang Nie ◽  
Weifeng Ma ◽  
Kai Xue ◽  
Junjie Ren ◽  
Wei Dang ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Test Method ◽  
Girth Welds

Evaluation of changes in mechanical properties of O-ring in one-piece and two-piece ball retained implant-supported overdentures: A three-year retrospective study.

2021 ◽  
Author(s):  
Fathima Banu Raza ◽  
Anand Kumar
Keyword(s):  
Mechanical Properties ◽  
Wear Resistance ◽  
Retrospective Study ◽  
Statistical Analysis ◽  
Wear Rate ◽  
Digital Camera ◽  
Maximum Displacement ◽  
Pin On Disc ◽  
The One ◽  
Insight Into

The o-rings in ball retained overdentures deteriorate with time and need replacement to restore the retentive quality. We evaluated retrospectively the mechanical properties of o-rings after 3 years in function in one and two-piece implant-supported overdentures. The o-rings were retrieved from one-piece (Myriad snap, Equinox-Straumann, 3.3 x 13mm) and two-piece (Neo Biotech, 3.3 x 13mm) implant-supported overdenture patients. A total of 16 pairs of matrices were tested for wear, type of damage and elasticity using Pin on Disc method, USB Digital Camera in 30x zoom and Universal Tensile Machine respectively. The statistical analysis for independent groups were done with the Mann-Whitney U test. Assessment of used O-rings showed 84% more wear in the two-piece system with an abrasive type of damage while 46% wear in the one-piece system with a compressive type of damage. The o-rings in one-piece system showed increase in elongation and maximum displacement to 2% and 7% respectively, while two-piece system showed decrease in elongation and maximum displacement by 13% and 6% respectively. In one-piece system, the loss of retention was more with slow wear rate and in two-piece system, the wear resistance of O-rings decreased due to increased stiffness. Further studies to evaluate the changes in O-ring with increased sample size and at interval 1 year will pave way for insight into the progressive changes in the mechanical properties of an O-ring.

3D Microstructure and Micromechanical Properties of Minerals in Vanadium-Titanium Sinter

2019 ◽  
Vol 38 (2019) ◽  
pp. 101-112 ◽  
Author(s):  
Runsheng Xu ◽  
Wei Wang ◽  
Weilin Chen ◽  
Bin Jia ◽  
Zhihui Xu
Keyword(s):  
Mechanical Properties ◽  
Fracture Toughness ◽  
3D Reconstruction ◽  
Structural Characteristics ◽  
Longitudinal Axis ◽  
Calcium Ferrite ◽  
Serial Sectioning ◽  
3D Microstructure ◽  
Computer Aided ◽  
Vanadium Titanium

AbstractTo investigate the structural characteristics and mechanical properties of minerals in vanadium-titanium sinter, the 3D microstructures of the sinter were reconstructed by serial sectioning in conjunction with computer-aided 3D reconstruction techniques The results show that hematite and magnetite in vanadium-titanium sinter will grow along the longitudinal axis direction and act as a scaffold. The size of magnetite crystals in vanadium-titanium sinter is much smaller than that in traditional sinter. The calcium ferrite in vanadium-titanium sinter is columnar-like, while that in traditional sinter is needle-like. The decreasing order of the microhardness value of minerals in the two sinters is hematite, calcium ferrite, magnetite and silicate, while the fracture toughness value from highest to lowest is calcium ferrite, hematite, magnetite and silicate. The comprehensive hardness value and comprehensive fracture toughness value of vanadium-titanium sinter are both less than these of traditional sinter.

EFFECT OF BORATES AND SILICATES ON WEARING PROPERTIES OF MAO COATINGS

2016 ◽  
Vol 24 (05) ◽  
pp. 1750061
Author(s):  
Yu ZHANG ◽  
YAN-WEI ZHAO ◽  
NAN XIANG ◽  
REN-GUO SONG
Keyword(s):  
Mechanical Properties ◽  
Aluminum Alloy ◽  
Treatment Time ◽  
Microarc Oxidation ◽  
Smooth Structure ◽  
Electrolytic Bath ◽  
Optimum Treatment ◽  
The One ◽  
Wear Tests

In the present study, microarc oxidation (MAO) coatings were formed on ZL101A aluminum alloy in an electrolytic bath containing 3[Formula: see text]g/L KOH [Formula: see text] 2[Formula: see text]g/L Na2WO[Formula: see text] 4[Formula: see text]g/L KF. The morphology and wearing behavior were investigated. In both electrolytes, the additives were borates (Na2B4O718[Formula: see text]g/L) and silicates (Na2SiO3 18[Formula: see text]g/L), respectively. It was found that the coating formed in borates-containing electrolyte was of compact and smooth structure than that of the one formed in silicates-containing electrolyte at the optimum treatment time. It was found that all the coatings were composed of á-Al2O3 and ã-Al2O3. The microhardness and wear tests proved that the coating formed in borates-containing electrolyte was having better mechanical properties than those of the coating formed in silicates-containing electrolyte.

Improving the Mechanical Properties of AZ31 Mg Alloy by High Ratio Extrusion

2006 ◽  
Vol 503-504 ◽  
pp. 865-870 ◽  
Author(s):  
Yongjun Chen ◽  
Qu Dong Wang ◽  
Jianguo Peng ◽  
Chun Quan Zhai
Keyword(s):  
Mechanical Properties ◽  
High Strength ◽  
High Ratio ◽  
Extrusion Ratio ◽  
Mg Alloy ◽  
Fine Grained ◽  
Az31 Mg Alloy ◽  
Industry Applications ◽  
One Step ◽  
The One

Experiments were conducted both to evaluate the potential for grain refinement, the subsequent mechanical properties at room temperature in samples of AZ31 Mg alloy and also to investigate the relationship between one-step and two-step high ratio extrusion (HRE). The one-step HRE was undertaken using a high extrusion ratio of 70:1 at 250, 300 and 350°C. And the two-step HRE was conducted with an extrusion ratio of 7 for the first step at 250, 300 and 350°C, followed by a second-step extrusion with an extrusion ratio of 10 at 250, 300 and 350°C. The initial grain size in the AZ31 ingot was 100μm and that after one-step HRE became similar to 5μm, after two-step HRE at 250, 300 and 350°C were 2, 4, 7μm, respectively, resulting in superior mechanical properties at ambient temperature. The microstructure of two-step HRE was finer and uniformer than that of one-step HRE and the strength of one-step and two-step HRE were similar, moreover, the elongation of one-step HRE was improved markedly than that of two-step HRE. Dynamic recrystallization and adjacent grain broking during HRE is introduced to explain the effects of one-step and two-step HRE on the microstructure and mechanical properties of AZ31 Mg alloy. The current results imply that the simple HRE method might be a feasible processing method for industry applications, and the multiply steps extrusion are effective to fabricate high strength of fine grained hcp metals.

scholarly journals Monitoring the degradation of partly decomposable plastic foils

2014 ◽  
Vol 6 (1) ◽  
pp. 39-44
Author(s):  
Gabriella Rétháti ◽  
Krisztina Pogácsás ◽  
Tamás Heffner ◽  
Barbara Simon ◽  
Imre Czinkota ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Molecular Mass ◽  
Structural Changes ◽  
Thermoplastic Starch ◽  
Medium Density ◽  
Insulating Layer ◽  
Elongation At Break ◽  
One Year ◽  
The One

Abstract We have monitored the behaviour of different polyethylene foils including virgin medium density polyethylene (MDPE), MDPE containing pro-oxydative additives (238, 242) and MDPE with pro-oxydative additives and thermoplastic starch (297) in the soil for a period of one year. A foil based on a blend of polyester and polylactic acid (BASF Ecovio) served as degradable control. The experiment was carried out by weekly measurements of conductivity and capacity of the soil, since the setup was analogous to a condenser, of which the insulating layer was the foil itself. The twelve replications allowed monthly sampling; the specimen taken out from the soil each month were tested visually for thickness, mechanical properties, morphological and structural changes, and molecular mass. Based on the obtained capacity values, we found that among the polyethylene foils, the one that contained thermoplastic starch extenuated the most. This foil had the greatest decrease in tensile strength and elongation at break due to the presence of thermoplastic starch. The starch can completely degrade in the soil; thus, the foil had cracks and pores. The polyethylene foils that contained pro-oxydant additives showed smaller external change compared to the virgin foil, since there was no available UV radiation and oxygen for their degradation. The smallest change occurred in the virgin polyethylene foil. Among the five examined samples, the commercially available BASF foil showed the largest extenuation and external change, and it deteriorated the most in the soil.

Sign in / Sign up

Export Citation Format

Share Document