Surface Finish Materials Research Articles

Evaluating the Effects of Building Characteristics of Worship Auditoriums on Speech Intelligibility in Makurdi Metropolis

To enjoy the comfort of the indoor environment of any enclosed space, it is important to have a reasonable measure of understanding of any spoken word in the room. In line with the above this study assessed the characteristics of worship auditoriums with regards to speech intelligibility in Makurdi metropolis with the view to identifying building characteristics that affect speech intelligibility worship auditoriums. The study was carried out through the employment of walkthrough survey and physical observation; a well structured checklist was employed for the study. Measurements of lengths, widths and heights were carried out, from which the room volume was obtained to have an insight of the space under consideration. The auditoriums of ten worship centres in Makurdi Metropolis were studied. The findings that showed all the auditoriums were rectangular in shape. It was found that there was use of inappropriate application of materials for surface finishes in the auditoriums. In terms of room volume, it was found that G recorded the highest volume with 17064.00m3 while E recorded the lowest volume of 756.00m3 . The mean volume of the auditoriums was calculated to be 517.64m3 , the Standard Deviation (SD) was 4733.44 and the Coefficient of Variation (CV) was found to be 81.36%. The study recommended that proper selection and application of surface finish materials be ensured during construction of worship centres. Also, that acoustic treatment is applied in auditoriums where defects are identified, with the aim of effectively enhancing speech intelligibility in worship auditoriums in Makurdi Metropolis.

Carbon Capture and Storage through Upcycling of Suberinic Acid Residues in Wood Composites Finishing

Finishing coatings used in the wood-based composite industry play a key role in the final appearance of the finished product. However, the use of such coatings is not only for aesthetic purposes, but also to protect the product against surface damage and moisture or to minimize the emission of harmful substances. The latter is an extremely important factor in terms of safety for both the manufacturer and the user, which is why the emissivity test is one of the most important tests conducted in this case. Carbon-rich materials, such as those remaining from the extraction of birch bark, can fulfill the role of minimizing the emission of harmful substances. In this article, an attempt to create coatings in the form of a film by combining a biopolymer with suberinic acid residues (SARs) was made. Two types of biopolymers were used, polylactide (PLA) and polycaprolactone (PCL), in various polymer–SAR ratios. Suberinic acid as a residue is a raw material that can potentially contribute positively to the fixing of CO2 from the atmosphere, which creates the possibility for further use. As part of this study, the obtained coatings were tested in terms of scratch resistance, relative hardness, cold liquids, total volatile organic compounds (TVOCs), formaldehyde emission, surface absorption, etc. Differences between the polymers used and the effect of the SAR additive on selected surface properties were demonstrated. The addition of carbon-rich SAR significantly improves gas barrier properties of the PLA- and PCL-based surface finishing materials. The relative hardness and scratch resistance also increased with rising SAR content. However, the increasing content of SAR filler acts as a limiter in the depth of penetration of the deposited surface finishing materials onto the wood surface. It is possible to state that this innovative approach regarding (1) the utilization of biopolymers as a matrix, instead of conventional, crude oil-based resins, and (2) the incorporation of post-processed carbon-rich waste lignocellulosic materials to produce the surface finishing and/or protective films has been confirmed.

The effect of microstructure for Ni-based surface finishing thin film on corrosion behavior

Electroless and electroplated single-layer Ni and multilayer Ni/Pd/Au were used as surface finishing materials for automobile device substrates. When the samples were placed in a chamber with various gaseous SO2 concentrations, better corrosion resistance was observed for single-layer electroless Ni and multilayer electroplated Ni/Pd/Au compared with their well-crystalline electroplated and electroless counterparts, respectively. Electrochemical analysis and materials characterization are adopted to investigate the disparate corrosion behaviors. Galvanically displaced Pd(P) and immersion Au with a high grain boundary density provided a large number of diffusion paths for the increased growth of corrosion products on the electroless Ni/Pd/Au surface than on the electroplated surface. Reduced hydrogen gas formed blisters exerting pressure on the grain boundaries and causing defects that may enhance the diffusion of the atoms. These results proved that the microstructure and crystallinity of surface finishing films have a predominant effect on their corrosion behaviors.

Small‐scale assessment method for the fire resistance of historic plaster system and timber structures

AbstractThe primary protection against the charring of timber is ensured by protection materials. Today, there are only a limited number of materials given in design codes as fire protection materials for timber. Historic surface finish materials such as plasters have rarely been studied with respect to fire; no design values exist in the current fire part of Eurocode 5. Full‐scale fire testing is costly to assess the fire performance of material combinations, thus this study presents a useful tool that is specifically tailored to evaluate the fire protection ability of materials in small‐scale. A review of conducted tests demonstrate that the cone heater of a cone calorimeter is a dependable device to estimate the charring performance of protected timber specimens as the test results approximate the ones obtained from furnace tests. This work contributes to the assessment of fire resistance performance of various combinations and types of plaster systems found in existing timber buildings that often require an individual approach for an adequate fire risk analysis and design decisions to meet current fire safety regulations with respect to the load‐bearing capacity and compartmentation of building structures. Increased knowledge on the fire protection performance of traditional plasters is believed to facilitate their wider use in timber buildings, primarily to preserve their significance as part of the cultural built heritage.

An ultrawideband balanced antipodal vivaldi antenna for medical imaging applications with performance analysis for different surface finish materials

An ultrawideband balanced antipodal vivaldi antenna for medical imaging applications with performance analysis for different surface finish materials

The Effect of Surface Finishes on Rising Damp in Oriented Strand Board

It is known that oriented strand board (OSB) is prone to water absorption. This characteristic of OSB is undesirable, it can have a negative impact on the physical and mechanical properties of the material and it can also make it prone to attack from wood-destroying insects, rot or mould. The research follows previous work of the authors related to optimisation of surface finishes for OSB in order to increase its moisture resistance. The aim of the research is to compare the rise of dampness in test specimens with different types of coating, spray, primer and waterproofing under predefined conditions. The paper contains a definition of the basic material, test specimens and test methods, and covers 8 different types of surface finish materials selected for application to the test specimens. The results include graphs showing rise of dampness in the test specimens for each day of observation. The results are also discussed and in the conclusion the results are evaluated. The results of the experiments confirm the assumption that the choice of surface finish has a significant effect on slowing down the rise of dampness in OSB.

SARS-CoV-2 Viability on 16 Common Indoor Surface Finish Materials.

This study investigated the stability of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on 16 common environmental surface materials. SARS-CoV-2 is the causative agent of severe coronavirus disease, a significant public health concern that quickly led to a pandemic. Contamination of environmental surface materials is of concern, with previous studies identifying long-term detection of infectious particles on surfaces. These contaminated surfaces create an increased risk for contact transmission. Surface materials were inoculated with 10,000 plaque forming units and samples were collected 4, 8, 12, 24, 30, 48, and 168 hours post infection (hpi). Viral titers were determined for each sample and time point using plaque assays. Nonparametric modeling utilized the Turnbull algorithm for interval-censored data. Maximum likelihood estimates for the survival curve were calculated. Parametric proportional hazards regression models for interval censored data were used to explore survival time across the surface materials. There was a sharp decline in recoverable virus after 4 hpi for all tested surfaces. By 12 hpi, infectious SARS-CoV-2 was recoverable from only four surfaces; and by 30 hr, the virus was recoverable from only one surface. There were differences in survival curves based on the materials although some groups of materials are similar, both statistically and practically. While very low amounts of infectious SARS-CoV-2 are recoverable over time, there remains a risk of viral transmission by surface contamination in indoor environments. Individuals and institutions must follow appropriate procedures to decontaminate indoor environment and increase diligence for hand hygiene and personal protective equipment.

Mechanical Characterization and Machining of MgAZ91D/SiC/Al2O3MMC by Squeeze Cast Method

In the automotive industry, the high surface finish and superior mechanical property materials are prepared with the help of the squeeze casting process. The paper investigates on the chosen materials of MMC cast using magnesium alloy (Mg-AZ91D) reinforced with various %wt of silicon carbide (SiC) also aluminum oxide (Al2O3) of nano particulates (20 nm). The preferred squeeze casting technique produces magnesium matrix composites along with silicon carbide (SiC) and aluminum oxide (Al2O3) particulates direct to an absolute drenched of inside the liquefy magnesium of hybrid metal matrix composite. Using CNC lathe and orthogonal array (L9), Magnesium metal matrix composites (Mg-AZ91D) are machined. To determine Metal Removal Rate (MRR) and Surface roughness (Ra) with various input parameters having the CNC lathe. Magnesium metal matrix composites (Mg-MMC) also, comparing the results with the unreinforced magnesium alloy with reinforcement of silicon carbide (SiC) and aluminum oxide (Al2O3) of nano particulates, Mechanical properties of the Magnesium metal matrix composite (Mg-MMC) and optimal machining parameters are evaluated.

Fire protection provided by clay and lime plasters

ABSTRACT Plasters are traditional surface finish materials in timber buildings. Today, the lack of fire performance data and design guidelines place such ecological materials at a disadvantage since plaster is not considered as a fire protection material for timber. This study aims to provide an up-to-date overview of performed fire tests accompanied by investigations on thermal properties of selected ready-mix clay and lime plasters. Design parameters of plasters for the fire design of timber structures are proposed following the safety philosophy of EN 1995-1-2. Numerical heat transfer simulations provide sufficient agreement with furnace test results for undercoat clay plaster. The mechanical fastening system of a plaster (e.g. reed mat) on timber demonstrates paramount importance when determining the charring rate of timber and the fall-off time of plaster. The structural integrity and fire performance of plasters should be further investigated due to their various recipes and numerous fastening systems on timber. Further research in full-scale is needed to confirm the recommended design parameters.

Material properties of clay and lime plaster for structural fire design

SummaryClay and lime plaster are traditional surface finish materials used on historic timber walls and ceilings. Today, hardly any fire technical properties or design parameters exist that consider such plasters as fire protection materials for timber structures. This hinders the fire assessment of existing building structures and disadvantages their use in modern design solutions where healthy and sustainable materials are increasingly favoured. This research follows the safety philosophy of EN 1995‐1‐2 to describe the fire protection ability of plasters. This paper investigates the temperature‐dependent thermal properties of historic plasters by presenting series of material‐specific tests and furnace tests carried out under standard fire exposure conditions. Experimental studies are supported by numerical heat transfer simulations. Results demonstrate particularities between the fire protection ability of clay and lime plaster, however, highlight the need for further investigations in terms of their thermophysical performance and standardisation at the European level. Design parameters are presented and discussed in future perspective. This work demonstrates a basic research to plan and design full‐scale fire tests according to EN 13381‐7:2019.

Optimisation of Surface Finishes for Oriented Strand Board in Order to Increase Its Moisture Resistance

The purpose of the research is the optimisation of surface finishes for application to oriented strand board (OSB) in order to increase its moisture resistance. The aim of the research is to compare test specimens with different types of coating, spray, primer and waterproofing under predefined conditions and different forms of moisture exposure. The paper contains a definition of the basic material, test specimens and test methods, and covers 8 different types of surface finish materials selected for application to the test specimens. The results include graphs showing growth in humidity over time, specifically graphs showing the causal relationship between increases in weight and moisture absorption, as well as graphs depicting swelling in thickness. The results are also discussed. In the conclusion the results are evaluated and an outline of the next steps to take with regard to further research is formulated. The results are of benefit to all subjects concerned with wooden structures in which OSB is used, both at the design stage and at the stage of the preparation and execution of construction with respect to unpredictable weather conditions that can irreparably damage unprotected structures. In addition, these are results which are important for the operation of buildings during which a suitable surface finish can alleviate the consequences of later accidents and defects. They may also be beneficial during the construction of buildings from structural insulated panels who’s facing most often consists of OSB. Construction periods tend to be adversely affected by changes in the weather. The application of suitable surface finishes to OSB immediately during the prefabrication stage could eliminate this issue.

Dissolution Rate of Electronics Packaging Surface Finish Elements in Sn3.0Ag0.5Cu Solder

A clear understanding of the characteristics of solder wetting to component terminations is critical for establishing thermal process profiles that ensure acceptable solder joint integrity. For example, component gold plating thickness as well as the soldering process temperature and time must be carefully controlled to prevent embrittlement by the gold/tin intermetallic compound. The electronics industry has successfully applied the results published in 1969 by W.G. Bader to relate process temperature and time to surface finish dissolution rates in defining acceptable soldering process profiles for tin/lead surface finishes. To date, there is no single comprehensive data set for these materials that is comparable to the Bader work. To address this need, solder dissolution experiments modeled on the Bader work were conducted using Sn3.0Ag0.5Cu (SAC305) solder with gold, silver, palladium, platinum, copper and nickel samples. In these experiments, samples were immersed in a solder pot, and the resulting material dissolution was determined for different solder temperatures and immersion times. This paper describes the test approach for measuring the solder dissolution of these materials and tabulates dissolution rates suitable for optimizing soldering process profiles for electronic assemblies. The dissolution rates of the surface finish materials were found to typically be about 50% higher for the lead-free SAC305 solder than tin–lead solder.

Effects of Surface Finish Material on Millimeter-Wave Antenna Performance

Recently, the popularity of millimeter-wave circuits has increased. One of the main reasons for this increase is offering a wide frequency band and high-speed data transfer. Due to the manufacturing requirements, these circuits are covered with surface finishes. Although surface finish protects the exposed copper circuitry, these additive layers on copper foil affect the electrical properties of the conductor. Unlike previous papers in the literature, this paper deals with the effects of surface finishing materials on millimeter-wave antennas instead of transmission lines. With this aim, a differential dual exponentially tapered slot antenna (DETSA) that has almost constant gain, beamwidth, and low reflection coefficient over the entire V-band is designed. A balun is designed for one-port measurement of the differential antenna. Then, two widely used surface finish solutions, namely, electroless nickel immersion gold (ENIG) and immersion silver (IAg), are applied to the copper profile of the differential integrated antenna combined with balun. The structures are simulated with a widely used full-wave analysis tool. The antenna without surface finish, with ENIG, and IAg surface finishes are fabricated and measured. A peak gain of 8.7–9 dBi is measured in the 57–64-GHz ISM band for the antenna without surface finish. Only 0.2-dB decrease in maximum gain is observed with 0.4- $\mu \text{m}$ silver. With ENIG surface finish, the gain decrease is observed as 1 dB. ENIG has higher loss due to flow of current in nickel material having lower conductivity compared to copper. The measurement results are consistent with the numerical results.

Solder-Joint Reliability of a Radar Processor for Semi-Autonomous Driving Applications

Abstract Radar is currently employed in automotive applications to provide the range, angle, and velocity of objects using RF waves (77GHz). This paper outlines solder joint reliability of a specific micro-processor that processes data received from a SRR (short range radar operating from 0.2 to 30 meters). It is a powerful digital signal processing accelerator, which targets safety applications that require a high Automotive Safety Integrity Level (ASIL-B). The paper explores the package design and construction, SMT (surface mount technology) assembly, and board level reliability testing of various BGA pad surface finish and solder ball alloy materials on a 0.65 mm pitch, 10 × 10 mm body 141 MAPBGA (mold array process-ball grid array) package. The package configurations include two BGA pad surface finishes (Ni/Au and OSP [organic solderability protectant]) and three solder alloys (SnAg, SAC405, and SAC-Bi [a Bi containing SAC derivative]). Solder joint reliability analysis was performed through AATS (air-to-air thermal shock) between 40°C and +125°C and JEDEC Drop Testing at 1500G's. Thermal shock was extended until at least 75% of the populations failed, which was well past the points needed to qualify the packages for the intended end-use applications. The evaluations of the micro-processor indicate that the MAPBGA package can meet the ASIL-B specification requirements with optimized combinations of BGA pad surface finish and solder alloy. The focus of this paper was to determine the baseline solder-joint thermal shock and JEDEC drop performance with varied BGA pad surface finish and solder ball alloy materials.

Earthquake-Induced pallet sliding in industrial racking systems

This paper discusses the sliding behaviour of pallets in industrial racking systems under dynamic actions. For this purpose, a summary of the results of an extensive series of dynamic shake-table tests are presented; complete results of this extensive testing campaign may be found in a recently published book. Dynamic and seismic tests have been performed using three beam types with different surface finish materials, in both the Cross-Aisle (CA) and Down-Aisle (DA) directions. Lower and upper bound accelerations were determined from the uniaxial dynamic tests. Several phenomena related to deformations of the supporting beams (i.e. in- and out-of-plane bending) were found to affect the pallet behaviour, in both the CA and DA directions, with sliding occurring at very low acceleration levels. The same behaviour was observed during uniaxial earthquake tests. For biaxial seismic testing, lower bound acceleration in the CA direction was higher than in dynamic cyclic tests, whereas the opposite was observed in the DA direction.

Oil Absorption Capacity of the Contact Surfaces in Metal-Forming Processes

The results of studying the surfaces roughness of rolls, dies, and workpiece are presented and analyzed. Recommendations are formulated on selecting rational surface finishing methods for rolls and dies and methods for preparation of blanks for drawing. The oil absorption capacity of surfaces depending on their roughness caused by the machining method used is determined. The results can be used for choosing surface finishing methods, tools, and materials, depending on the intended metal-forming process.

Surface Finish Materials: Considerations for the Neonatal Intensive Care Unit (NICU)

NICU surface material finishes require consideration to support the design of a healing environment benefitting the patients, families, and caregivers. The evidence from a growing body of research that focuses on the healthcare facility design influence on occupant outcomes suggests that material finishes for the NICU contribute to the clinical, operational and social dimensions of health outcomes. The main surface finishes in the NICU are the flooring, ceiling, walls, work surfaces, and upholstery. Appropriate specifications assure that materials are durable, cleanable, easy to disinfect, attractive, comfortable, minimize unwanted noise, and addresses safety concerns. Most of the literature that met inclusion focused on sound and hospital associated infection. Other articles indicated outcomes related to environmental and human health, fatigue and discomfort, stress, anxiety, and medical errors.

Analysis of grease contamination influence on the internal radial clearance of ball bearings by thermographic inspection

One of the most important factors influencing ball bearings service life is its internal radial clearance. However, this parameter is also very complex because it depends on applied radial load and ball bearings dimensions, surface finish and manufacturing materials. Thermal condition of ball bearings also significantly affects internal radial clearance. Despite many researches performed in order to find out relevant facts about different aspects of ball bearings thermal behaviour, only few of them are dealing with the real working conditions, where high concentration of solid contaminant particles is present. That?s why the main goal of research presented in this paper was to establish statistically significant correlation between ball bearings temperatures, their working time and concentration of contaminant particles in their grease. Because of especially difficult working conditions, the typical conveyor idlers bearings were selected as representative test samples and appropriate solid particles from open pit coal mines were used as artificial contaminants. Applied experimental methodology included thermographic inspection, as well as usage of custom designed test rig for ball bearings service life testing. Finally, by obtained experimental data processing in advanced software, statistically significant mathematical correlation between mentioned bearings characteristics was determined and applied in commonly used internal radial clearance equation. That is the most important contribution of performed research - the new equation and methodology for ball bearings internal clearance determination which could be used for eventual improvement of existing bearings service life equations.

Evaluation of Thermal Degradation of Wood with Environmentally Problematic Application of Coatings

For predicting the behavior of wood products with a final finish by applying polyurethane coatings (mainly solvent) under realistic conditions of use is extremely important to monitor all quality characteristics (physical, mechanical, chemical and performance) as well as fire-engineering based on selected characteristics of thermal degradation The paper presents proposals evaluation criteria (total weight loss, maximum rate of burning, time to reach maximum speed of burning, ignition time) for test radiant heat source for wood surface finishing materials by polyurethane coatings for a comprehensive assessment of fire-technical and environmental safety materials for predicting the behavior of these materials in response to fire.

발수제가 수성페인트의 물리적 성능에 미치는 영향

This study is to analyze durability of water-repellent paints mixed with water-repellents as outer surface finishing materials, and evaluate its feasibility. General functions and water-repelling effects were tested, and the feasibility was evaluated based on the test results. The experimental results of heat conduction durability, air permeability, absorption, and bond strength suggested that water-repellent paints mixed with water-repellents were suitable for finishing materials. Considering overall general durability performances, stable mixing ratios were 2, 5, and 8%.