scholarly journals A New Microhardness Testing Method on Grating Films

2020 ◽  
Vol 2020 ◽  
pp. 1-6
Author(s):  
Haitao Ma ◽  
Yi Jin ◽  
Jirigalantu

The manufacturing process of large-area, high-precision gratings is a very complicated and time-consuming process. The hardness testing of grating films is an important step in the entire process. In order to simplify the manufacturing process of gratings, we have proposed a new method for testing microhardness based on tool edge indentation. Also, it unified tool adjustment and microhardness testing steps in the grating manufacturing process. First, a mathematical model of the relationship between tool load and indentation contour length is established. The model parameters were then modified using tool indentation experiments with different loads. When measured with a nanoindenter, the average hardness of the grating film was 447 MPa. The hardness value of the grating film obtained by our proposed method is almost the same as that measured by the nanoindenter, and the maximum deviation is about 2.2% of the average hardness value. The experimental results show that our proposed method can replace the microhardness test method of using a nanoindenter. Therefore, the disadvantages of using a nanoindenter to test the hardness of a grating film are avoided, such as the limited sample size, the sensitivity of the indenter to the roughness of the film and the depth of the indentation, and the accuracy of film testing, and the efficiency of grating ruling can be improved.

TAPPI Journal ◽  
2009 ◽  
Vol 8 (6) ◽  
pp. 24-28
Author(s):  
CORY JAY WILSON ◽  
BENJAMIN FRANK

TAPPI test T811 is the specified method to ascertain ECT relative to box manufacturer’s certification compliance of corrugated fiberboard under Rule 41/ Alternate Item 222. T811 test sample heights were derived from typical board constructions at the time of the test method’s initial development. New, smaller flute sizes have since been developed, and the use of lighter weight boards has become more common. The T811 test method includes sample specifications for typical A-flute, B-flute, and C-flute singlewall (and doublewall and triplewall) structures, but not for newer thinner E-flute or F-flute structures. This research explores the relationship of ECT sample height to measured compressive load, in an effort to determine valid E-flute and F-flute ECT sample heights for use with the T811 method. Through this process, it identifies challenges present in our use of current ECT test methods as a measure of intrinsic compressive strength for smaller flute structures. The data does not support the use of TAPPI T 811 for ECT measurement for E and F flute structures, and demonstrates inconsistencies with current height specifi-cations for some lightweight B flute.


1986 ◽  
Vol 14 (4) ◽  
pp. 201-218 ◽  
Author(s):  
A. G. Veith

Abstract This four-part series of papers addresses the problem of systematic determination of the influence of several tire factors on tire treadwear. Both the main effect of each factor and some of their interactive effects are included. The program was also structured to evaluate the influence of some external-to-tire conditions on the relationship of tire factors to treadwear. Part I describes the experimental design used to evaluate the effects on treadwear of generic tire type, aspect ratio, tread pattern (groove or void level), type of pattern (straight rib or block), and tread compound. Construction procedures and precautions used to obtain a valid and functional test method are included. Two guiding principles to be used in the data analyses of Parts II and III are discussed. These are the fractional groove and void concept, to characterize tread pattern geometry, and a demonstration of the equivalence of wear rate for identical compounds on whole tread or multi-section tread tires.


Author(s):  
O. P. Tomchina ◽  
D. N. Polyakhov ◽  
O. I. Tokareva ◽  
A. L. Fradkov

Introduction: The motion of many real world systems is described by essentially non-linear and non-stationary models. A number of approaches to the control of such plants are based on constructing an internal model of non-stationarity. However, the non-stationarity model parameters can vary widely, leading to more errors. It is only assumed in this paper that the change rate of the object parameters is limited, while the initial uncertainty can be quite large.Purpose: Analysis of adaptive control algorithms for non-linear and time-varying systems with an explicit reference model, synthesized by the speed gradient method.Results: An estimate was obtained for the maximum deviation of a closed-loop system solution from the reference model solution. It is shown that with sufficiently slow changes in the parameters and a small initial uncertainty, the limit error in the system can be made arbitrarily small. Systems designed by the direct approach and systems based on the identification approach are both considered. The procedures for the synthesis of an adaptive regulator and analysis of the synthesized system are illustrated by an example.Practical relevance: The obtained results allow us to build and analyze a broad class of adaptive systems with reference models under non-stationary conditions.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Satoshi Miyamoto ◽  
Zu Soh ◽  
Shigeyuki Okahara ◽  
Akira Furui ◽  
Taiichi Takasaki ◽  
...  

AbstractThe need for the estimation of the number of microbubbles (MBs) in cardiopulmonary bypass surgery has been recognized among surgeons to avoid postoperative neurological complications. MBs that exceed the diameter of human capillaries may cause endothelial disruption as well as microvascular obstructions that block posterior capillary blood flow. In this paper, we analyzed the relationship between the number of microbubbles generated and four circulation factors, i.e., intraoperative suction flow rate, venous reservoir level, continuous blood viscosity and perfusion flow rate in cardiopulmonary bypass, and proposed a neural-networked model to estimate the number of microbubbles with the factors. Model parameters were determined in a machine-learning manner using experimental data with bovine blood as the perfusate. The estimation accuracy of the model, assessed by tenfold cross-validation, demonstrated that the number of MBs can be estimated with a determinant coefficient R2 = 0.9328 (p < 0.001). A significant increase in the residual error was found when each of four factors was excluded from the contributory variables. The study demonstrated the importance of four circulation factors in the prediction of the number of MBs and its capacity to eliminate potential postsurgical complication risks.


2021 ◽  
Vol 11 (9) ◽  
pp. 3827
Author(s):  
Blazej Nycz ◽  
Lukasz Malinski ◽  
Roman Przylucki

The article presents the results of multivariate calculations for the levitation metal melting system. The research had two main goals. The first goal of the multivariate calculations was to find the relationship between the basic electrical and geometric parameters of the selected calculation model and the maximum electromagnetic buoyancy force and the maximum power dissipated in the charge. The second goal was to find quasi-optimal conditions for levitation. The choice of the model with the highest melting efficiency is very important because electromagnetic levitation is essentially a low-efficiency process. Despite the low efficiency of this method, it is worth dealing with it because is one of the few methods that allow melting and obtaining alloys of refractory reactive metals. The research was limited to the analysis of the electromagnetic field modeled three-dimensionally. From among of 245 variants considered in the article, the most promising one was selected characterized by the highest efficiency. This variant will be a starting point for further work with the use of optimization methods.


2014 ◽  
Author(s):  
Tao Chen ◽  
Ping Chen ◽  
Harry Montgomerie ◽  
Thomas Hagen ◽  
Ronald Benvie ◽  
...  

Abstract Turbulent flow, especially around chokes, downhole safety valves and inflow control devices, favors scale deposition potentially leading to severe loss of production. Recently, scale formation under turbulent conditions has been studied and progressed, focused on the bulk precipitation (SPE164070) and a small bore valve loop test (SPE 155428). However, bulk precipitation is not fully representative the surface deposition in the fields and the Reynolds number of modified loop is unknown. The relationship between a measured Reynolds number and surface deposition up until this study has not been addressed. A newly developed test methodology with rotating cylinder has been applied to generate high shear rate and evaluate surface deposition with Reynolds numbers up to ~41000. The relationship between Reynolds number and surface deposition is addressed. Using this highly representable test method for BaSO4 scale deposition, several different generic types of inhibitor chemistries, including polymers and phosphonates, were assessed under different levels of turbulence to evaluate their performance on surface deposition. The results showed it is not always true that higher turbulence results in higher dose of inhibitor being required to control scale. It is inhibitor chemistry and mechanisms dependent. The scale inhibitorscan be classified as three types when evaluating the trend of mass deposition versus Reynolds number and the morphology of the crystals deposited on the metal surface. ➢ Type 1: Crytal growth inhibitors. The mass of surface deposition increases with the increase of turbulence, along with smaller crystals.➢ Type 2: Dispersion and crystal growth inhibitor. The higher the turbulence, the less mass deposition, along with smaller crystals.➢ Type 3: Dispersion scale inhibitors. The higher the turbulence, the less mass deposition. The size of the crystals has no major change. This paper gives a comprehensive study of the effect of flow condition on the scale surface deposition and inhibition mechanisms. In addition, it details how this methodology and new environmentally acceptable inhibitor chemistry can be coupled to develop a chemical technology toolbox that also includes techniques for advanced scale inhibitor analysis and improved scale inhibitor retention, to design optimum scale squeeze packages for the harsh scaling conditions associated with turbulent flow conditions.


2014 ◽  
Vol 941-944 ◽  
pp. 1802-1807 ◽  
Author(s):  
Qian Liu ◽  
Jing Tao Han ◽  
Jing Liu ◽  
Xiao Xiong Wang

Rotary punching is a sheet metal blanking process which utilizes shearing tools fixed to a pair of rollers. The polyurethane pad is adopted as the die instead of rigid mold because it has the advantages of wide hardness range and high load-bear capacity. Due to the application of polyurethane pad, the surrounding region adjacent to the pierced hole will occur to plastically deform and deflect, which greatly differs from that in the conventional blanking. In this paper, the effects of blank material and thickness, polyurethane hardness, punch penetration depth on deformation behavior were mathematically analyzed and modeled, and then a series of experiments through varying process parameters were conducted to validate the relationship between process parameters and product quality. The degree of sample deflection was exactly measured by scanning electron microscope (SEM). The results show that the deformed area varies with different blank elongations and increases with increasing blank thickness for a given material. When polyurethane pad with low hardness level is employed, it results in large area deformation and quality degradation. Moreover, the deflection degree around the hole edge becomes more severe along with punch penetration, but the penetration depth along blank thickness is not in proportion to the amount of punch advancement.


2020 ◽  
pp. 096452842094604
Author(s):  
O Sang Kwon ◽  
Seong Jin Cho ◽  
Kwang-Ho Choi ◽  
Suk-Yun Kang ◽  
Suyeon Seo ◽  
...  

Background: Moxibustion treatment involves a combination of thermal and chemical stimulation applied by the combustion of moxa wool. The quality of moxa wool is considered to be an important factor in moxibustion treatment traditionally and clinically. However, despite its importance, quantitative and objective methods for determining moxa wool quality are lacking. Methods: Moxa wool and commercial indirect moxibustion (CIM) device specimens were randomly collected, dried and strained through sieves of various sizes for 10 h. After sieving, the residues remaining on each sieve were collected. The collected samples were weighed and microscopically observed. Results: In this study, we observed that fibres mainly remained on sieves sized 425 μm, and particles were smaller than 300 μm. The residues between 425 and 300 μm varied between the products. In addition, moxa wool for direct moxibustion (DMW) exhibited significantly more fibres than moxa wool for indirect moxibustion (IMW). Most of the CIM devices using moxa wool had a quality similar to IMW, except for one CIM brand using moxa wool that contained three times more waste particles than IMW. Conclusion: Based on the results of this study, we conclude that the sieving method is useful for testing the quality of moxa wool even after the CIM manufacturing process. The sieve sizes of 425 and 300 μm could be used as a yardstick to determine the quality of moxa wool. Although this approach requires larger scale validation against existing standard methodologies, we believe it has great potential to be used to improve and safeguard the quality of moxa wool contained in commercial moxibustion devices.


1972 ◽  
Vol 45 (1) ◽  
pp. 16-25 ◽  
Author(s):  
L. C. Coates ◽  
C. Lauer

Abstract The results of this study are conclusive. The ASTM D-2229 Test Method is not a reliable test for measuring adhesion of wire cords to rubber compounds. However, by using the basic design and modifying it, an accurate measurement of bond strength on a macroscopic level can be obtained. This test is insensitive for all practical purposes to compound physical properties and changes in cord diameter and embedded length—for both stranded and rod-like cords. It is also possible with this test to calculate the amount of stress that is exerted on the surface of the wire cord to determine the relationship between failing stress and the material strength of the rubber compound. Properly used, this new test should give the compounder a better tool to study the adhesion of compounds to metal.


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