scholarly journals Development of Microneedle Puncture Device that Prevents Buckling of Needle by Delivery Operation

2020 ◽  
Vol 32 (2) ◽  
pp. 382-389
Author(s):  
Masato Suzuki ◽  
◽  
Fuuta Motooka ◽  
Tomokazu Takahashi ◽  
Seiji Aoyagi
Keyword(s):  
Stainless Steel ◽  
Femtosecond Laser ◽  
Young’S Modulus ◽  
Young's Modulus ◽  
Load Condition ◽  
Plastic Plate ◽  
Stainless Steel Needle ◽  
Delivery Mechanism

Herein, using the micromachining technology, we propose a microneedle delivery mechanism that is similar to the lead delivery mechanism for a mechanical pencil. This mechanism involves three parts: a needle grasping part, a needle advancing part, and a needle retainer. This mechanism advances the needle by repeating the following steps: 1) fix the needle in the grasping part; 2) simultaneously advance the grasping part and the needle using the advancing part; 3) release the needle from the grasping part; 4) retreat the grasping and the advancing parts to their initial positions. This operation advances the needle very slowly, thereby allowing the needle to puncture the skin without buckling, even if the needle has a narrow diameter. Each component of the puncture device was cut from a plastic plate using a femtosecond laser. We evaluated the performance of the device for a stainless steel needle of φ100 μm, and were successful in delivering the needle at approximately 100 μm/cycle under a no-load condition. We also succeeded in puncturing the same needle into a hydrogel (Young’s modulus of ∼0.08 MPa) using this device.

Characterization of Cofficient of Friction in Dry Contact for Control of Vibrations in Machine Systems

2000 ◽  
Author(s):  
Jamil Abdo ◽  
Kambiz Farhang ◽  
Glenn Meinhardt
Keyword(s):  
Surface Roughness ◽  
Stainless Steel ◽  
Young’S Modulus ◽  
Young's Modulus ◽  
Normal Load ◽  
304 Stainless Steel ◽  
Stick Slip ◽  
Dry Contact ◽  
Machine Systems ◽  
Alloy 6061

Abstract A 2k factorial experiment is performed to ascertain the effect of four factors and their cross influence on friction between dry surfaces. The factors in this study include materials Young’s modulus, applied normal load, surface roughness and relative surface speed. For each combination of factors four replicates in addition to two center points are used to obtain an average coefficient of friction for dry contact. In the experiment 304 Stainless Steel and Alloy 6061 Aluminum are employed to provide the high and low levels of Young’s modulus. Results suggest that Young’s modulus has the most significant influence followed by velocity/modulus cross-coupling, surface roughness, load, and modulus/roughness. Analyses are carried out separately for the 304 Stainless Steel and alloy 6061 Aluminum to remove the effect of Young’s modulus. The results are used to obtain iso-friction curves that serve to establish force-speed control for prevention of stick-slip vibration.

Stiffening Effects of Tubes in Heat Exchanger Tubesheet

1984 ◽  
Vol 106 (3) ◽  
pp. 237-246 ◽  
Author(s):  
T. Terakawa ◽  
A. Imai ◽  
K. Yagi ◽  
Y. Fukada ◽  
K. Okada
Keyword(s):  
Heat Exchanger ◽  
Young’S Modulus ◽  
Tube Wall ◽  
Young's Modulus ◽  
Perforated Plate ◽  
Load Condition ◽  
Experimental Tests ◽  
Uniaxial Tensile ◽  
Hydraulic Test ◽  
Tube Heat Exchanger

Strain-measuring tests were performed with strain gages on rectangular coupons taken from perforated plate with triangular pitch under both uniaxial tensile loads and pure bending loads. The effective Young’s modulus obtained from the tests have strong correlation with the values recommended by the ASME Code. Next, to evaluate the stiffening effects of tubes, similar strain-gage tests were performed for different types of perforated coupons. One type had the tubes strength welded into the penetration holes of the test coupons. Another type had the tubes both expanded and strength welded into the test coupons. Stiffening effects of tubes are clearly obtained from these tests. Judging from the effective Young’s modulus of triangular pitch obtained by the testing, the recommended minimum credit given to the tube wall is 50 percent under elastic load condition. In addition, for experimental tests on an actual large-sized shell-and-tube heat exchanger under hydraulic test condition, good correlation was obtained between calculated and measured stress when full credit was taken for the tube wall in the calculation.

scholarly journals Correlations of Geometry and Infill Degree of Extrusion Additively Manufactured 316L Stainless Steel Components

Materials ◽  
2021 ◽  
Vol 14 (18) ◽  
pp. 5173
Author(s):  
Tobias Rosnitschek ◽  
Andressa Seefeldt ◽  
Bettina Alber-Laukant ◽  
Thomas Neumeyer ◽  
Volker Altstädt ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Stainless Steel ◽  
Product Development ◽  
Young’S Modulus ◽  
Young's Modulus ◽  
Dimensional Accuracy ◽  
Product Development Process ◽  
Stainless Steel 316L ◽  
Before And After ◽  
Metal Extrusion

This study focuses on the effect of part geometry and infill degrees on effective mechanical properties of extrusion additively manufactured stainless steel 316L parts produced with BASF’s Ultrafuse 316LX filament. Knowledge about correlations between infill degrees, mechanical properties and dimensional deviations are essential to enhance the part performance and further establish efficient methods for the product development for lightweight metal engineering applications. To investigate the effective Young’s modulus, yield strength and bending stress, standard testing methods for tensile testing and bending testing were used. For evaluating the dimensional accuracy, the tensile and bending specimens were measured before and after sintering to analyze anisotropic shrinkage effects and dimensional deviations linked to the infill structure. The results showed that dimensions larger than 10 mm have minor geometrical deviations and that the effective Young’s modulus varied in the range of 176%. These findings provide a more profound understanding of the process and its capabilities and enhance the product development process for metal extrusion-based additive manufacturing.

Finite Element Method for Predicting the Cohesive Strength of DLC Film on 316L Stainless Steel by Four Point Bend Test and Validation with Experimental Results

2011 ◽  
Vol 264-265 ◽  
pp. 1823-1831
Author(s):  
Muhammad M. Morshed ◽  
Stephen M. Daniels ◽  
M.S.J. Hashmi
Keyword(s):  
Finite Element ◽  
Stainless Steel ◽  
Young’S Modulus ◽  
316L Stainless Steel ◽  
Mechanical Performance ◽  
Young's Modulus ◽  
Cohesive Strength ◽  
Bend Test ◽  
Deposition Pressure ◽  
Point Bend

The mechanical performance of DLC coatings on 316L stainless steel deposited by a saddle field fast atom beam source has been evaluated using the four point bend (FPB) test. Two different deposition parameters, pressure and current were varied when depositing the films. Load-displacement measurements were carried out during the bend test to determine the load corresponding to crack initiation. This load designated as the cohesive strength of the coating which is also called the cracking resistance of coating and provides a measure of the strength of the coating. The cohesive strength of the coating was calculated based on elementary beam theory. Scanning Electron Microscopy (SEM) was used to determine the location of the crack. Finite element analysis was used to predict the stress distribution across the coating thickness. The experimental work on FPB tests has been used to support the numerical (finite element) model for the determination and prediction of film cohesive strength. It was observed that at lower deposition current, the cohesive strength increases with increased deposition pressure whereas, for higher deposition current, these values do not increase with increasing deposition pressure. The model takes into account the film’s Young’s modulus, thickness and deposition pressure and current, and has shown that it is capable of predicting film cohesive strength when combined with a theoretical formulation for brittle fracture. It has been observed that the maximum stress develops at the outer surface of the film and propagates through the film-substrate interface. This result has only been validated for films with higher Young’s modulus compared to that of the substrate material.

Texture Characterization of Stainless Steel Cladded Layers of Process Vessels

2016 ◽  
Vol 879 ◽  
pp. 1588-1593 ◽  
Author(s):  
Joana Rebelo-Kornmeier ◽  
Wei Min Gan ◽  
M.J. Marques ◽  
A.C. Batista ◽  
Michael Hofmann ◽  
...  
Keyword(s):  
Stainless Steel ◽  
Young’S Modulus ◽  
Young's Modulus ◽  
Orientation Distribution ◽  
Distribution Functions ◽  
Protective Layers ◽  
Local Texture ◽  
Pole Figures ◽  
Gauge Volume ◽  
Texture Characterization

In this study local texture of process vessels made of carbon steel cladded by protective layers of stainless steel by submerged arc welding (SAW) were investigated by neutron diffraction using the diffractometer STRESSSPEC at FRM 2 (Garching, Germany). Different samples were prepared: as welded and as welded plus relevant industrial heat treatment. Local texture measurements with a gauge volume of 3 x 3 x 2 mm3 of the three cladding layers (at depths of 2 mm, 5 mm and 7.5 mm) for each sample were determined. Texture results indicated that there exists an annealed cube component in all the studied samples. Based on the measured pole figures at each depth and sample, the calculated orientation distribution functions data were used to calculate the Young's modulus with respect to the main welding directions. The calculated local and bulk anisotropic Young’s modulus in depth is presented and discussed.

On the Young's modulus of 304 L stainless steel thin films

2000 ◽  
Vol 45 (1) ◽  
pp. 33-37 ◽  
Author(s):  
B Boubeker ◽  
M Talea ◽  
Ph Goudeau ◽  
C Coupeau ◽  
J Grilhe
Keyword(s):  
Thin Films ◽  
Stainless Steel ◽  
Young’S Modulus ◽  
Young's Modulus

scholarly journals Changes in Intraocular Pressure after Transepithelial Photorefractive Keratectomy and Femtosecond Laser In Situ Keratomileusis

2021 ◽  
Vol 2021 ◽  
pp. 1-10
Author(s):  
Chien-Chih Chou ◽  
Po-Jen Shih ◽  
Hung-Chou Lin ◽  
Jun-Peng Chen ◽  
Jia-Yush Yen ◽  
...  
Keyword(s):  
Intraocular Pressure ◽  
Femtosecond Laser ◽  
Young’S Modulus ◽  
Young's Modulus ◽  
Laser In Situ Keratomileusis ◽  
Photorefractive Keratectomy ◽  
Linear Regression Models ◽  
Postoperative Changes

Purpose. To investigate the changes in intraocular pressure (IOP) and biomechanically corrected IOP (bIOP) in patients undergoing transepithelial photorefractive keratectomy (TPRK) and femtosecond laser in situ keratomileusis (FS-LASIK) and to determine the effects of preoperative biomechanical factors on IOP and bIOP changes after FS-LASIK and TPRK. Design. A retrospective comparative study. Methods. We retrospectively investigated the IOP and corneal biomechanical changes in 93 eyes undergoing FS-LASIK and 104 eyes undergoing TPRK in a clinical setting. Preoperative and postoperative data on ophthalmic and Corvis ST examinations, in vivo Young’s modulus, and noncontact tonometry were analyzed. Marginal linear regression models with generalized estimating equations were used for intragroup and intergroup comparisons of IOP and bIOP changes. Results. In the univariate model, IOP reduction after FS-LASIK was 2.49 mmHg higher than that after TPRK. In addition, bIOP reduction after FS-LASIK was 1.85 mmHg higher than that after TPRK. In the multiple regression model, we revealed that IOP reduction after FS-LASIK was 1.75 mmHg higher than that after TPRK. Additionally, bIOP reduction after FS-LASIK was 1.64 mmHg higher than that after TPRK. Postoperative changes in bIOP were less than those in IOP. In addition, Young’s modulus and CBI had no significant effect on postoperative IOP and bIOP changes. We establish a biomechanically predictive model using the available data to predict postoperative IOP and bIOP changes after TPRK and FS-LASIK. Conclusions. Reductions in IOP and bIOP after FS-LASIK were 1.75 mmHg and 1.64 mmHg, respectively, more than those after TPRK, after adjustment for confounders. We revealed that the type of refractive surgery and peak distance (PD) were significant predictors of postoperative IOP and bIOP changes. By contrast, depth of ablation showed a significant effect on only IOP changes.

Nanoindentation Characterization of Mechanical Properties of Ferrite and Austenite in Duplex Stainless Steel

2007 ◽  
Vol 26-28 ◽  
pp. 1165-1170 ◽  
Author(s):  
Xiu Fang Wang ◽  
Xiao Ping Yang ◽  
Zhen Dan Guo ◽  
Yin Chang Zhou ◽  
Hong Wei Song
Keyword(s):  
Mechanical Properties ◽  
Stainless Steel ◽  
Duplex Stainless Steel ◽  
Young’S Modulus ◽  
Young's Modulus ◽  
Hot Forging ◽  
Sample Surface ◽  
Cast Sample ◽  
The Difference

The mechanical properties of as-cast and hot-forging duplex stainless steel samples with the same compositions were characterized by nanoindentation. The effect of surface treating method and working state of the sample on the nanoindentation results of ferrite and austenite were discussed. The results show that the Young’s modulus and hardness of ferrite and austenite may be affected by the treating method of sample surface. The difference of Young’s modulus average of ferrite or austenite between as-cast and hot-forging duplex stainless steel samples is not great, but the hardness average of ferrite or austenite in hot-forging sample is obviously higher than those of as-cast sample. The difference of hardness between ferrite and austenite in the same sample is not great, but the young’s modulus of ferrite is higher than that of austenite.

Sign in / Sign up

Export Citation Format

Share Document