Standard Test Method For Measurement Research Articles

Thermal Effusivity Assessment of Sportswear Fabrics in the Dry State: Stacked and Air-Hoop Methods

Abstract In recent years, thermal effusivity, a property that describes the warm or cool touch perception, has gained significant attention in the apparel industry as it contributes to human thermophysiological comfort. The current study aims to explore the thermal effusivity of 27 sportswear fabrics, including woven and knitted structures with various fiber contents, using the stacked method (according to ASTM D7984-21, Standard Test Method for Measurement of Thermal Effusivity of Fabrics Using a Modified Transient Plane Source (MTPS) Instrument) and a modified air-hoop method. The results obtained revealed that the pressure range specified in ASTM D7984-21 (10–50 kPa) may cause fabric compression, resulting in the measurement of a material-based thermal effusivity rather than the fabric thermal effusivity. A pressure of 1 kPa was found to be more appropriate for obtaining accurate measurements of sportswear fabrics without altering their three-dimensional structure. Furthermore, a strong correlation was observed between the stacked and air-hoop methods for fabrics with thicknesses close to or greater than 0.4 mm. The air-hoop method simulates the configuration when the fabric is worn as part of a garment. The new knowledge provided by this research will enhance the accuracy of the thermal effusivity measurement of sportswear fabrics. It will contribute to the development of more comfortable fabrics considering realistic garment use scenarios.

Exploring variations to ASTM E336 directional sound source positioning

This paper explores variations to the procedures presented in ASTM E336 Standard Test Method for Measurement of Airborne Sound Attenuation between Rooms in Buildings. Per the Test Standard, directional sound sources must be aimed into corners away from the test partition. For source rooms horizontally adjacent to occupied spaces on all sides, multiple loudspeaker positions are needed to measure noise isolation in all directions. Measurements made in 4 office spaces are presented, each made in two ways: firstly in compliance with the Standard; and secondly, with sound sources orientated and operated differently, to explore whether using a single configuration of directional loudspeakers can produce similar results. Variations in the results are discussed, and suggestions are provided for future work.

Information Value of the Results of Examining Metallic Products by the X-Ray Computer Tomography Method

The information value of X-ray computer tomography (X-CT) lies in the quality and accuracy of its results. Despite indisputable advantages of X-CT in comparison with other non-destructive examination methods, it has not received widespread use in the industry in view of its high cost and low throughput capacity. In addition, in Russia there is no regulatory and technical framework that would stipulate a standard procedure for selecting the tomographic examination parameters, nor are there standard techniques for estimating the quality of X-CT results. In view of this circumstance, the article analyses the US standard ASTM E 1695 Standard Test Method for Measurement of Computed Tomography (CT) System Performance. This standard stipulates a procedure for quantitatively assessing the quality of tomograms of a cylindrical test specimen, namely, spatial resolution and contrast sensitivity. The standard describes methods and a mathematical tool for calculating the modulation transfer function (MTF), contrast discrimination function (CDF), and constructing a contrast-detail diagram (CDD), which takes into account the influence of both unsharpness and noise on the possibility of detecting a flaw of certain size and morphology. The MTF values obtained under specific scanning and reconstruction conditions are a quality indicator of the X-CT results for objects examined under the same scanning conditions and made of materials similar in terms of attenuation coefficient, and can be used to assess the sensitivity of examination by the X-CT method. The article defines artifacts as any discrepancy between the object’s reconstructed volume and real attenuation factors. The reasons why artifacts appear are explained, their images on tomograms are shown, and recommendations for minimizing them are given. Factors affecting the information value of the X-ray tomographic examination results are pointed out.

Recording studio sound isolation: A case study of challenges faced in measuring door transmission class (DTC) and noise isolation class (NIC) in small rooms

This case study examines the challenges faced in measuring the DTC and NIC between a recording studio control room and the studio recording space. Challenges included structural radiation around the tested partition, flanking paths, ADA ramp design, and improper use of the space during construction. The measurements were performed following the procedures of ASTM E2964-14 Standard Test Method for Measurement of the Normalized Insertion Loss of Doors and ASTM E336-19 Standard Test Method for Measurement of Airborne Sound Attenuation between Rooms in Budlings. The spaces were designed by an acoustical consultant and desired by the owner to have extremely high levels of sound isolation. Furthermore, the nature of the intended clientele necessitated high performance, a high finish level, and state of the art technology. The investigators were not part of the design team and were invited to measure the space to document and validate the final performance. This presentation will outline the findings, challenges in measurement, and the steps taken to increase the sound isolation performance.

An Alternative Method for the Invariant Threshold Force Evaluation in Incremental Step Loading Tests

Abstract Hydrogen embrittlement (HE) affects the main groups of metal alloys used in the industry, varying from steels to nickel-based corrosion-resistant alloys. It is estimated that 25 % of failures that occur in the oil and gas industry is caused by fracture associated with hydrogen. The incremental step loading (ISL) technique, put forward by ASTM F1624-18(2018), Standard Test Method for Measurement of Hydrogen Embrittlement Threshold in Steel by the Incremental Step Loading Technique, has been widely used for HE susceptibility evaluation. However, testing metallic materials, other than steels with hardness lower than 33 HRC, following the ASTM F1624 method proved that the invariant threshold force (Pth) determination is not possible. It was observed that the Inconel 718 under certain experimental conditions did not reach the advised 5 % of the fast fracture strength, PFFS, force drop as this material has a low crack growth rate because of its high ductility and low hydrogen diffusivity. Although another force drop value could be adopted, it would still be an arbitrarily defined value that could not be applied to other materials without further study. To overcome this problem, a robust and efficient method of easy implementation was developed and validated. The new approach considers the relative variation, VΔF¯, associated with the difference between the input force (set point value) and the measured force as an alternative to a notch fracture strength force drop percentage. This method does not contradict the ASTM F1624 determinations as it too is based on the force drop values. The Pth values obtained for the AISI 4140 steel using the ASTM F1624 standard corroborate the values obtained based on the proposed method. This method allows the assessment of the Pth values in Inconel 718, as they were corroborated by crack nucleation observations at the notch root using a high-resolution scanning electron microscopy after the ISL tests. The obtained results show that the proposed method proved to be robust, efficient, and of easy implementation. Thus, it can be used as an alternative to the Pth evaluation of steels with a hardness less than 33 HRC and for metallic materials not covered by the ASTM F1624 standard.

On the Possible Relaxation of the ASTM E1921 and ASTM E1820 Standard Specifications with Respect to the Use of the Mini-CT Specimen

Specimen miniaturization is gaining a lot of interest in the fracture mechanics community thanks to recent methods accounting for specimen size correction. In particular, the miniature compact tension (mini-CT) specimen is gaining large international interest for irradiated surveillance materials used to monitor irradiation damage in reactor pressure vessels. Because of the limited available amount of some of these materials, eight mini-CT specimens can easily be machined from one broken Charpy specimen, avoiding the need of consuming surveillance materials. Specimen reorientation also becomes possible to investigate anisotropic effects. At this stage, ASTM E1921, Standard Test Method for Determination of Reference Temperature, T0, for Ferritic Steels in the Transition Range(Superseded), the standard for brittle fracture, and ASTM E1820, Standard Test Method for Measurement of Fracture Toughness (Superseded), the standard for ductile fracture, are used for this geometry, although it does not fully satisfy the requirements of the standards. In particular, the specifications on the specimen dimensions relative to the specimen width are tight, given that the tolerances are a fraction of the specimen width. Given that the actual dimensions of the specimen are taken into account in the calculations, the analysis described in this article shows that the tight dimensional accuracy is not necessary. Moreover, given the limited thickness of the specimen, the curvature of the fatigue precrack tends to deviate from a quasi-straight front. As a result, a large number of mini-CT specimens do not fulfill the standard requirements with respect to crack front curvature. Previous tests demonstrated that actual cracks excessive curvature lead to similar results when compared with artificial fatigue quasi-straight cracks. The objective of this article is to experimentally demonstrate that some of the standard requirements can be relaxed without jeopardizing the quality of test data, in terms of master curve and crack resistance curve.

Algorithm for J-Integral Measurements by Digital Image Correlation

The work is devoted to the testing of the algorithm for calculating J-integral based on the construction of vector fields by digital image correlation (DIC) method. A comparative analysis of J-integral values calculated using DIC and instrumental data obtained in accordance with ASTM E 1820 “Standard Test Method for Measurement of Fracture Toughness” has made. It is shown that this approach can be used for cases when the standard technique for measuring the J-integral cannot be applied, or the standard technique does not allow achieving the required accuracy for the integral determination in local areas of the loaded material.

Evaluation of Anodized Aluminum Sealing through Electrochemical Noise as a Control Method

The present work shows the results obtained in current time series, localized index (LI) and noise resistance (Rn) for 6061 aluminum in different conditions: unsealed anodized, sealed anodized, unsealed colored and sealed colored, evaluating the sealing quality with NaCl 3.5M at different exposure times, this with the objective of analyzing the corrosion mechanisms present in the specimens. The validation of electrochemical noise tests was performed by obtaining admittance by electrochemical impedance spectroscopy and using ASTM B457 "Standard Test Method for Measurement of Impedance of Anodic Coatings on Aluminum” was determined if the anodized surface was sealed correctly, thus having an optimal methodology for the control of anodized aluminum sealing.

How to Improve the Quality of Laboratory Permeability Tests in Rigid-Wall Permeameters: A Review

ASTM D2434, Standard Test Method for Permeability of Granular Soils (Constant Head) (Withdrawn 2015), and ASTM D5856, Standard Test Method for Measurement of Hydraulic Conductivity of Porous Material Using a Rigid-Wall, Compaction-Mold Permeameter, are used to measure the saturated hydraulic conductivity, Ksat, of soil specimens in rigid-wall permeameters (RWPs). Several laboratory conditions and settings explain why the tests do not give Ksat values but unsaturated hydraulic conductivity, K(Sr), values for a degree of saturation, Sr, that is often in the 80–85 % range. It is suggested to improve ASTM D2434 and ASTM D5856 by adding two requirements: (1) use a watertight-and-airtight RWP (a control method is provided), and (2) use a mass-and-volume method to obtain the true Sr value of the tested specimen. To illustrate potential detrimental impacts of current standards, the article describes a case where sand was planned to be used as a filter layer for a solid waste project. Large quantities of sand had been delivered at the construction site. The Ksat value of the sand, as compacted, had to exceed 10−4 m/s to satisfy a bylaw. To prove this, two laboratories followed ASTM D2434 for their tests but found K values of 5−8 × 10−5 m/s. The project engineers asked the authors to make verifications. The prior tests were redone and yielded similar K values. However, it was found that the real Sr value was close to 80 % instead of being assumed to be 100 %. Other tests were performed after using vacuum and deaired water in a watertight-and-airtight permeameter: the specimens reached Sr = 100 % and gave Ksat values of about 2 × 10−4 m/s, 3–4 times higher than initial tests. As a result, the already delivered sand satisfied the bylaw condition and there was no need to return large quantities of sand already delivered, to purchase a new type of sand after having done laboratory tests, and to have a time delay in construction, all these items having a high economic impact.

Application of the ASTM D5470 standard test method for thermal conductivity measurements of high thermal conductive materials

Purpose: The purpose of the present study was to demonstrate the procedure for determining the thermal conductivity of a solid material with relatively high thermal conductivity, using an original self-designed apparatus. Design/methodology/approach: The thermal conductivity measurements have been performed according to the ASTM D5470 standard. The thermal conductivity was calculated from the recorded temperature values in steady-state heat transfer conditions and determined heat flux. Findings: It has been found from the obtained experimental results that the applied standard test method, which was initially introduced for thermal conductivity measurements of thermal interface materials (TIMs), is also suitable for materials with high thermal conductivity, giving reliable results. Research limitations/implications: The ASTM D5470 standard test method for measurement of thermal conductivity usually gives poor results for high conductive materials having thermal conductivity above 100 W/mK, due to problems with measuring heat flux and temperature drop across the investigated sample with reasonably high accuracy. Practical implications: The results obtained for the tested material show that the presented standard test method can also be used for materials with high thermal conductivity, which is of importance either for the industrial or laboratory applications. Originality/value: The thermal conductivity measurements have been carried out using an original self-designed apparatus, which was developed for testing broad range of engineering materials with high accuracy.

Phase II Results of an Analytical Round Robin for Elastic-Plastic Analysis of Surface Cracked Plates

Abstract The second phase of an analytical round robin for the elastic-plastic analysis of surface cracks in flat plates was conducted under the auspices of ASTM Interlaboratory Study 732. The interlaboratory study (ILS) had ten participants with a broad range of expertise and experience, and experimental results from a surface crack tension test in 4142 steel plate loaded well into the elastic-plastic regime provided the basis for the study. The participants were asked to evaluate a surface crack tension test according to the version of the surface crack initiation toughness testing standard published at the time of the ILS, ASTM E2899-13, Standard Test Method for Measurement of Initiation Toughness in Surface Cracks under Tension and Bending. Data were provided to each participant that represented the fundamental information that would be provided by a mechanical test laboratory prior to evaluating the test result. Participants were asked to interpret the test according to E2899, including evaluation of crack-front constraint, determination of a critical initiation angle along the crack front, determination of the deformation regime of the test, and determination of the critical J-integral value. The choice of finite element analysis constitutive models and treatment of the stress-strain data was left to the discretion of the participants. The hope was that this process would familiarize participants with the standard and provide the task group with very helpful feedback regarding the interpretation of the requirements as they are written. Overall the participants’ test analysis results were in good agreement and constructive feedback was received that has resulted in an improved published version of the standard E2899-15.

ASTM E08.07.09 Analytical Round-Robin on the Use of DC Electrical Potential Difference for the Measurement of Crack Size in Ductile Fracture Testing.

The Direct Current Electrical Potential Difference (DCEPD) technique has been used for many years in fatigue and fracture testing for monitoring crack propagation in metallic materials. The principle of DCEPD methods is that when a constant current flows through a cracked specimen, the voltage change measured across the crack plane can be analytically related, empirically related, or both, to the change in crack size. In fatigue testing, performed within the limits of Linear Elastic Fracture Mechanics, crack propagation is the sole source of potential change. In ductile fracture testing, additional contributions from specimen dimension changes and crack-tip plastic deformation (blunting) have to be accounted for and distinguished from the DCEPD increase caused by crack growth. The ASTM E08.07.09 Task Group, formed in 2013 and chaired by the author, has been developing an annex for ASTM E1820, Standard Test Method for Measurement of Fracture Toughness, which focuses on the use of DCEPD measurements for the prediction of crack size and crack extension in ductile fracture toughness tests. This article presents the analysis of an analytical round-robin, in which 8 participants analyzed 24 existing fracture toughness data sets using two different approaches, based on the analysis of the displacement versus DCEPD and force versus DCEPD, respectively. The comparison between these two approaches and the implications for the ASTM E1820 annex being developed are the focus of this article.

Hydrogen Embrittlement Susceptibility of Bainite for High Strength Steel Fasteners

Industrial fasteners of two different steel microstructures were investigated using incremental step load testing based on ASTM F1624, Standard Test Method for Measurement of Hydrogen Embrittlement Threshold in Steel by the Incremental Step Loading Technique. The microstructures consisted of tempered martensite and lower bainite. The purpose was to compare hydrogen embrittlement (HE) susceptibility at different hydrogen charging conditions. The results showed that lower bainite exhibited marginally lower HE susceptibility when tested under moderate hydrogen charging conditions (e.g., −1.0 V). At the most severe hydrogen charging potential of −1.2 V, both microstructures are equally embrittled. These results are explained by the differences in the transport and trapping kinetics of hydrogen in bainite as compared to martensite.

Modified acoustic transmission tube apparatus incorporating an active downstream termination.

Current techniques for measuring normal incidence sound transmission loss with a modified impedance tube, or transmission tube, require setting up two different absorbing termination loads at the end of the downstream tube [ASTM E2611-09, Standard Test Method for Measurement of Normal Incidence Sound Transmission of Acoustical Materials Based on the Transfer Matrix Method (American Society for Testing and Materials, West Conshohocken, 2009)]. The process of physically handling the two required passive absorbing loads is a possible source of measurement errors, which are mainly due to changes in sample test position, or in test setup re-assembly, between measurements. In this paper, a modified transmission tube apparatus is proposed for non-intrusively changing the downstream acoustic load by means of a combined passive-active termination. It provides a controlled variable sound absorption which simplifies the setup of standard two-load techniques, without the need of physically handling the apparatus during the tests. This virtually eliminates the risk of errors associated with the physical manipulation of the two passive terminations. Transmission loss measurements in some representative test conditions are reported, showing improvements over current implementations, in reducing by approximately 50% the measurement variations associated with the setup of the two required absorbing terminations. Measurement results agree within 0.4 dB (maximum difference in high resolution broadband), and 0.04 dB (mean difference in 1/3-octave bands), with those obtained using standard passive two-load methods.

Fracture Toughness Evaluation of Zr-2.5Nb Pressure Tubes Manufactured Employing Double Forging for PHWR700

The need for improvement of the in-reactor performance of Zr-2.5 % Nb pressure tubes arose because of the higher than expected diametral creep rates and variability in axial elongation observed in some of the pressure tubes of 220 MWe Indian pressurized heavy water reactors (IPHWR220). A systematic study revealed that the pressure tubes used in various IPHWR220 had variations in microstructure, mechanical properties, texture, and chemical composition. The forthcoming PHWR700 is expected to operate at a higher temperature than that of IPHWR220 pressure tubes coupled with ∼3 % partial boiling toward the outlet end. The IPHWR220 pressure tubes were manufactured by NFC (Hyderabad, India) using the combination of extrusion-double pilgering with intermediate annealing and with 20 % final cold work. PHWR700 pressure tubes have been manufactured using a combination of forging-extrusion-single pilgering routes. The fracture behavior of cold-worked and stress-relieved Zr-2.5Nb pressure tube material manufactured employing a forging route for PHWR700 is described in this work as a function of hydrogen content (4 and 60 wppm), temperature (25°C–300°C), and sample location. Fracture toughness tests were carried out as per ASTM E1820-06 [ASTM E1820-06: Standard Test Method for Measurement of Fracture Toughness—Designation, Annual Book of ASTM Standards, ASTM International, West Conshohocken, PA] using curved compact tension specimens of 17 mm width. The crack growth was along the axial direction of the tube and was measured using the direct current potential drop (DCPD) technique. The fracture toughness of as-received samples show weak dependency on test temperature, whereas samples having 50 ppm hydrogen show typical S curve behavior and regain toughness above 150°C. The variation in fracture toughness across tube length was within scatter band.

Sorptivity Ratio and Compressive Strength of Alkali-Activated Blast Furnace Slag Paste

Abstract The initial/secondary absorption and compressive strength of alkali-activated slag (AAS) paste has been investigated. Emphasis has been given to secondary absorption of AAS paste based on the method described in ASTM C1585-04 [Standard Test Method for Measurement of Rate of Absorption of Water by Hydraulic Cement Concretes, Annual Book of ASTM Standards, ASTM International, West Conshohocken, PA, 2004, pp. 1–4]. The paste was produced by activating blast furnace slag with sodium hydroxide/potassium hydroxide and sodium silicate solution. The major parameters studied were alkali content, silicate content, and the type of activator. Experimental investigation revealed that initial rate of absorption (Si) and secondary rate of absorption (Ss) decreases with increase in alkali and silicate content up to a certain limit with an increase in compressive strength. The maximum compressive strength was found to be 50.40 MPa for the specimens having lowest sorptivity. It was also found that the sorptivity ratio (Si/Ss) plays a significant role on compressive strength in turn on the durability of AAS composites. This paper is an attempt to introduce the simple method of measuring initial and secondary sorptivity described in ASTM C1585-04 to study the strength and durability of AAS. The microstructure study was carried out using SEM/EDAX.

A Method to Obtain Straight Crack Fronts During Pre-Cracking of Compact Tension Specimens

Abstract A common problem during pre-cracking of compact tension (CT) specimens is skewed crack fronts. It is also one of the most common reasons for which tests according to, for instance, ASTM E1820-11: Standard Test Method for Measurement of Fracture Toughness, Annual Book of ASTM Standards, ASTM International, West Conshohocken, PA, 2012, do not give valid results. This problem is normally a result of the fact that specimens and fixtures are not perfectly aligned, even when the testing setup meets the requirements of ASTM standards. In the present investigation, aluminum bushings have been used to rearrange the loads transferred from the testing machine to the specimens. Geometrical errors were deliberately introduced to the testing setup so that the specimens were asymmetrically loaded. The introduced errors were, however, within the tolerances of ASTM standards. Steel specimens with two different notch types, Chevron and straight notches, were tested, both with and without aluminum bushings. The specimens were pre-fatigued and thereafter broken under monotonic loading. The specimen crack lengths were measured and validated according to ASTM E1820-11. The results related to pre-fatigued specimens with aluminum bushings were shown to be valid, whereas the results for specimens without bushings did not meet the ASTM standards requirements.

Complement to standard method for measuring normal incidence sound transmission loss with three microphones

Complement to standard E2611-09 of the American Society for Testing and Materials [Standard Test Method for Measurement of Normal Incidence Sound Transmission of Acoustical Materials Based on the Transfer Matrix Method (American Society for Testing and Materials, New York, 2009)] is proposed in order to measure normal incidence sound transmission loss of materials in a modified impedance tube using a three-microphone two-load or one-load method. The modified tube is a standard two-microphone impedance tube, where a third microphone is mounted on a movable hard termination. This method is conceptually identical to the four-microphone two-load or one-load method described in the standard; however, it requires fewer transfer functions and one microphone less. The method is validated on (1) symmetrical homogeneous and (2) non-symmetrical non-homogeneous specimens.

Regarding the Value Reported for the Term “Spatial Gradient Magnetic Field” and How This Information Is Applied to Labeling of Medical Implants and Devices

translational attraction for a medical device that is conducted according to the proce-dure described by the American Society for Testing and Materials (ASTM) Internation-al Designation F 2052–06e1, “Standard Test Method for Measurement of Magnetically Induced Displacement Force on Passive Im-plants in the MR Environment.” Using this technique, a test apparatus with a protractor (also called the fixture) is placed in an MR system with a horizontal magnetic field at the point of the highest accessible spatial gradi-ent magnetic field [6]. In general, the highest spatial gradient magnetic field used to assess translational attraction for a medical device is located off-axis, at a side wall, and near the opening of the bore of the scanner [1, 3]. Alternatively, the medical device is assessed for translational attraction at the point where the highest deflection angle occurs in associ-ation with the particular MR system used for the assessment. The angular deflection of the device from the vertical is measured and the translational attraction is calculated [6].Notably, the placement of the test fixture (apparatus with the protractor) in the MR system is at a position where it can be used properly (i.e., securely positioned) for the test procedure. This is almost always a worst-case position of greatest attractive force that the patient with the device will pass through when entering the bore of the MR system for an examination.For example, Figure 1 shows the measure -ment of translational attraction using the de -flection angle test as it was applied to evaluate an endoscope adapter. Note the positioning of the test fixture (the apparatus with the pro-tractor). It was placed off-axis near the mouth of the bore of the scanner at the point of the highest accessible spatial gradient magnetic field (i.e., 720 gauss/cm for the 3-T MR sys-tem used for this test). The deflection angle was 36° for the endoscope adapter.

Determination of the Water Diffusivity of Concrete Using Drying/Absorption Test Results

Abstract Experimental procedures such as ASTM C1585, “Standard Test Method for Measurement of Rate of Absorption of Water by Hydraulic-Cement Concretes,” and ISO12572 have been recently developed to determine the rate of moisture transmission through hydrated cement systems. However, these methods do not provide an actual transport parameter that can be used in chloride ingress models to predict the service-life of concrete structures. This study focused on the development a reliable method to measure the nonlinear moisture diffusivity of concrete. The approach is based on the analysis of drying and wetting experiments performed with concrete samples of different thicknesses. The transport parameter is obtained by using Richards’ water transport model to analyze the mass variations measured during the tests. The method was tested over a wide range of different concrete mixtures produced with different water/cement ratios. Results indicate that the nonlinear function used to reproduce the mass variation curves must exhibit a strong increase for high water content values. The water diffusivity equation derived from this analysis allows reproducing the behavior of concrete during both the drying and absorption experiments using the same water transport model.