Measurement Of Adhesion Strength Research Articles

Improving Cleaning Efficiency through the Measurement of Food Fouling Adhesive Strength.

This study aims to investigate the impacts of factors, including textural properties, surface roughness, and contact angle, on the cleaning performance of food soils and develop a preliminary mathematical model to predict the cleaning score, depending on the soil-surface properties. The force required to remove soil from the surface was determined by a texture analyzer equipped with a newly designed probe. Potato puree and egg yolk soils showed high adhesive forces compared to other deposits. Margarine required the lowest force to detach from the surfaces. A soil-surface characteristic number (SSCN) was constructed from the results of contact angle, roughness, and textural analysis to predict the cleaning score depending on the soil-surface properties. The experimental work presented indicates that a higher SSCN was associated with lower cleaning scores for soil-surface combinations. Furthermore, a predictive model was developed to define the relationship between cleaning scores and SSCN. The applicability of the model was validated by measuring the cleaning performance of caramel and pudding soils on glass, porcelain, and stainless-steel household surfaces by using an automatic method. Therefore, it can be concluded that the SSCN approach can be improved in further studies to predict cleaning scores of soil-surface combinations in the experimental rig or automatic dishwasher.

2D magnesium phosphate resorbable coating to enhance cell adhesion on titanium surfaces

Titanium and its alloys are essential metals for orthopedic implant manufacturing due to their exceptional mechanical properties and biocompatibility, used extensively for treating various orthopedic conditions. However, Titanium (Ti) implants have a disadvantage due to lack of bioactivity, potentially affecting osseointegration and osteoconductive capabilities, and may take several months to integrate with bone tissue. In this work, we prepared a layer of 2D magnesium phosphate (MgPi) coating on the surface of titanium surfaces via the spin-coating technique. Various techniques were used to study the phase composition of the coatings, including FTIR, Raman spectroscopy, NMR, and XRD analysis. Morphology and chemical analysis were performed using Atomic force microscopy and SEM/EDX. Nano-scratch test and water contact angle measurements were used to measure adhesion strength and wettability. In addition, in vitro cell assays were used to assess cell adhesion and viability to determine how the MC3T3-E1 osteoblast-like cells reacted to the different treated Ti substrates. AFM results showed that the surface roughness became lower after coatings. MgPi-coated samples showed higher hydrophilicity, protein adsorption, and cell viability than uncoated samples. The nano-scratch test showed that the MgPi coating showed better adherence to chemically and thermally treated samples compared to untreated samples. The deposited MgPi coating has good adhesion to the Ti-substrates. Most significantly, compared to uncoated control (Ti) (p < 0.005) and chemically treated coated samples CT-MgPi (p < 0.005), MC3T3-E1 cell proliferation was significantly increased on thermochemical coated surfaces. These findings point to resorbable two-dimensional MgPi coatings as a potential candidate for promoting Ti implant osseointegration.

Round-Robin Study for Ice Adhesion Tests

Ice adhesion tests are widely used to assess the performance of potential icephobic surfaces and coatings. A great variety of test designs have been developed and used over the past decades due to the lack of formal standards for these types of tests. In many cases, the aim of the research was not only to determine ice adhesion values, but also to understand the key surface properties correlated to low ice adhesion surfaces. Data from different measurement techniques had low correspondence between the results: Values varied by orders of magnitude and showed different relative relationships to one another. This study sought to provide a broad comparison of ice adhesion testing approaches by conducting different ice adhesion tests with identical test surfaces. A total of 15 test facilities participated in this round-robin study, and the results of 13 partners are summarized in this paper. For the test series, ice types (impact and static) as well as test parameters were harmonized to minimize the deviations between the test setups. Our findings are presented in this paper, and the ice- and test-specific results are discussed. This study can improve our understanding of test results and support the standardization process for ice adhesion strength measurements.

Effects of surface treatment method and fabric type on adhesion between PP material and artificial fabrics

Polypropylene (PP) is an exceptional engineering plastic owing to its cost-effectiveness, durability, lightweight nature, high heat resistance, and chemical stability. It is commonly bonded with fabrics to enhance its aesthetic appeal, particularly when used in automotive interiors and various other applications. Therefore, it is necessary to ensure strong adhesion between the PP substrate and fabric. In this study, we analyze the impact of various surface-treatment methods on the surface properties and adhesive strength of PP substrates, with the objective of increasing the bond strength between PP injection-molded products and artificial leather fabrics. In this study, woven and nonwoven fabric-type artificial leather fabrics, composed of polyurethane, are used. The PP substrate is subjected to three surface treatment methods: plasma, flame, and primer coating treatments. Surface analyses are performed to assess the effect of each treatment method, and adhesive strength measurements are performed using a adhesive to bond the PP substrate and fabrics. The adhesive strengths and peel morphologies are thoroughly examined. The results indicate that the plasma-treated PP substrates exhibit the highest adhesive strengths. The findings of this study can provide valuable guidance for enhancing the adhesion between PP injection-molded products and fabrics for various industrial applications.

Evaluation of the shear adhesion strength of impact ice by a new method

Aircraft icing has a detrimental effect on flight safety. The design of aircraft anti-icing/de-icing systems requires a thorough comprehension of the adhesion between the ice and the substrate. In this research, the multi-hole rotating cylinder method (MHRC) is developed in an icing wind tunnel. Simulations of interfacial stress show that ice thickness does not change the evenness of stress, whereas reducing the contact area can impair uniformity. Moreover, the ice layer would not experience any cohesive damage during the experiments. The shear ice adhesion strength is evaluated using the methodology outlined in this research. At lower temperatures, glaze ice demonstrates a rise in its shear adhesion strength, while the change trend is the opposite for rime ice. The lowest adhesion strength is observed at the medium volume diameter (MVD) of 45 µm. Furthermore, the growing liquid water content (LWC), rough surfaces, and surface painting will enhance the interface adhesion of ice to the substrate to varying degrees. Stainless steel substrate exhibits higher adhesion strength with ice as compared to aluminum and titanium. In addition, superhydrophobic surfaces have proven to possess a significant reduction in adhesion strength at higher temperature. The proposed experimental method and platform afford accurate measurements of the shear adhesion strength of impact ice in the icing wind tunnel.

Assessment of the effect of accelerated ultraviolet aging on mini‐PV modules encapsulated with different poly(ethylene‐co‐vinyl acetate) formulations

AbstractOne of the hindering issues for the long‐term reliability of the photovoltaic (PV) modules is the degradation of poly(ethylene‐co‐vinyl acetate) (PEVA)—a popular encapsulant material. As a globally accepted practice, PEVA is required to have the vinyl acetate (VA) content between 28–33% by weight for encapsulation application in the PV modules. Recent studies have indicated stability improvements in the bare encapsulant layer when the VA content is reduced up to 18%. However, effect of UV aging on the PEVA films encapsulated using these VA contents have not been studied at the module level. Therefore, in this work, we have fabricated mini‐modules containing PEVA films that contain 18, 24 or 33% VA content and have subsequently been subjected to UV aging (1000 hours at 340 nm wavelength and 65C). The assessment of the durability at both the mini‐module and materials level has been made using various characterization techniques such as current–voltage characteristics, adhesion strength measurement, fluorescence imaging and spectra, FTIR, Raman spectra, volume resistivity and TGA. YI for the free‐standing films of PEVA18, PEVA24 and PEVA33 after 1000 hours of UV aging was slightly less than the YI values for the corresponding laminated films of PEVAs in mini‐PV modules after similar hours of aging. This work shows for the first time that increasing the VA content in PEVA increases the fluorescence intensity and contour size in the encapsulated polymer after UV aging. FTIR analysis indicates deacetylation of PEVA33 which resulted in discoloration (increased ΔYI) and has adversely affected the adhesion strength and power output after UV aging. Compared to PEVA33, the modules containing PEVA18 and PEVA24 are resilient against UV aging for all the properties. Hence, this study recommends using PEVA with 24% VA content as an encapsulant as it presents best combination of the adhesion strength and the environmental stability.

Research on normal ice adhesion strength in icing wind tunnel

Aircraft icing seriously jeopardizes flight safety. The design of aircraft anti-icing/de-icing systems requires a thorough understanding of the adhesion between the ice and the substrate. In this research, an experimental device that can be housed within a wing is designed and constructed. Simulation analysis of the interfacial stresses is performed, which reveals that increasing the load and the interface size led to a deterioration in the uniformity of stresses at the interface. In addition, the ice layer does not undergo cohesive damage during the tests. The normal ice adhesion strength is evaluated in an icing wind tunnel using the methodology outlined in this paper. Glaze ice exhibits an increase in normal adhesion strength at lower temperatures, whereas the trend is reversed for rime ice. The minimum adhesion strength occurs near the medium volume diameter (MVD) of 30 µm. Furthermore, the normal strength is significantly enhanced by increase in wind speed and surface roughness, as well as by surface painting. The adhesion strength of aluminum substrates to ice is greater compared to titanium and stainless steel. Compared to shear adhesion strength, normal adhesion strength is less sensitive to various influencing factors. The proposed experimental framework provides precise measurement of normal adhesion strength of impact ice in the icing wind tunnel.

Analysis of Tempering Effects on LDS-MID and PCB Substrates for HF Applications

Mechatronic Integrated Devices or Molded Interconnect Devices (MID) are three-dimensional (3D) circuit carriers. They are mainly fabricated by laser direct structuring (LDS) and subsequent electroless copper plating of an injection molded 3D substrate. Such LDS-MID are used in many applications today, especially antennas. However, in high frequency (HF) systems in 5G and radar applications, the demand on 3D circuit carriers and antennas increases. Electroless copper, widely used in MID, has significantly lower electrical conductivity compared to pure copper. Its lower conductivity increases electrical loss, especially at higher frequencies, where signal budget is critical. Heat treatment of electroless copper deposits can improve their conductivity and adhesion to the 3D substrates. This paper investigates the effects induced by tempering processes on the metallization of LDS-MID substrates. As a reference, HF Printed Circuit Boards (PCB) substrates are also considered. Adhesion strength and conductivity measurements, as well as permittivity and loss angle measurements up to 1 GHz, were carried out before and after tempering processes. The main influencing factors on the tempering results were found to be tempering temperature, atmosphere, and time. Process parameters like the heating rate or applied surface finishes had only a minor impact on the results. It was found that tempering LDS-MID substrates can improve the copper adhesion and lower their electrical resistance significantly, especially for plastics with a high melting temperature. Both improvements could improve the reliability of LDS-MID, especially in high frequency applications. Firstly, because increased copper adhesion can prevent delamination and, secondly, because the lowered electrical resistance indicates, in accordance with the available literature, a more ductile copper metallization and thus a lower risk of microcracks.

Measuring adhesion strength of epoxy-based adhesives under quasi-static and dynamic loading conditions

Adhesively bonded joints are very common in aerospace applications. They are used in the fabrication of metal and composite components as well as in their repair work. Besides subjecting the interface to more uniform stress distribution, the bonded joints are simple and more efficient when compared to mechanical fastening. Since the reliability of components and structures depends upon the strength of bonded joints, adhesion strength has become an essential design and fabrication parameter. In this investigation, the interface strength between the metallic base and epoxy-based adhesive is assessed by performing quasi-static and extreme dynamic experiments. New test methods are developed by performing computational analysis with the objective of nullifying the stress concentration effect near the interface edge. Quasi-static adhesion tests performed using modified butt-joint specimens exhibit the interface strength between the aluminum and adhesive as 3.07 MPa. Upon subjecting the interface to a strain rate of ∼107/s by employing laser-induced stress waves, the interface strength is evaluated to be 213 MPa. The laser spallation technique, combined with the Michelson interferometer, was used to perform the optical measurements.

Assessment of Cementitious Ceramic Tile Adhesives in the Light of Repeatability and Reproducibility of the Tensile Adhesion Strength Measurements.

The paper presents the results of tensile adhesion strength measurements of ceramic tile adhesive (CTA) stored in various conditions performed by ten operators in one laboratory using the same equipment and auxiliary materials. The obtained results allowed the authors to estimate the repeatability and reproducibility of the tensile adhesion strength measurement method using the methodology following ISO 5725-2:1994+AC1:2002. Standard deviations of repeatability ranging from 0.09 to 0.15 for the general means value in the range of 0.89-1.76 MPa and standard deviations of reproducibility ranging from 0.14 to 0.21 for the same general means content indicate that the accuracy of tensile adhesion strength measurement method is not high enough. From the group of ten operators, five perform tensile adhesion strength measurements daily, the remaining five perform other measures, and the results obtained by professionals and non-professionals showed no significant differences. In light of the obtained results, compliance assessment with this method with the criteria set out in the harmonized standard EN 12004:2007+A1:2012 carried out by different operators may be divergent, and there is a significant risk of incorrect assessments. This risk is additionally increasing in the case of the evaluation conducted by market surveillance authorities, which use the simple acceptance rule that does not consider measurement variability.

Experimental rig for ice accretion and adhesion strength measurement for air cycle machine system

Air cycle machines (ACM) which are part of the air-conditioning pack in every aircraft, are one such turbomachinery device that can be affected by icing issues particularly at the turbine end. Current ice protection solutions for the air cycle machines use a heating system on the downstream pipe to heat the surface, using electric resistance heaters or hot air coming from the ACM compressor stage. Both solutions require high energy, hence the need to reduce energy consumption through the development of passive energy-saving solutions.Clean Sky 2 ERICE project aims at developing an eco-friendly and cost-effective hydrophobic / ice-phobic solution able to resist ice adhesion in the ACM turbine scroll and its downstream pipe. This paper discusses the implementation of an experimental rig to reproduce the ice formation and accretion conditions within the ACM and a new shear test method to measure the ice adhesion strength on existing and new solutions in the form of coatings. The flow through the ACM turbine exhaust has also been characterized for the first time in published literature. The results from the ice accretion and adhesion tests show that hydrophobic coatings developed for the purposes of ice protection perform better than the current industry baseline material for ACM turbine scroll pipe internal surface. While these coatings could not be used to prevent accretion, they do help in reducing adhesion of ice to the surface.

Quantifying cell adhesion through forces generated by acoustic streaming

The strength of cell adhesion is important in understanding the cell’s health and in culturing them. Quantitative measurement of cell adhesion strength is a significant challenge in bioengineering research. For this, the present study describes a system that can measure cell adhesion strength using acoustic streaming induced by Lamb waves. Cells are cultured on an ultrasound transducer using a range of preculture and incubation times with phosphate-buffered saline (PBS) just before the measurement. Acoustic streaming is then induced using several Lamb wave intensities, exposing the cells to shear flows and eventually detaching them. By relying upon a median detachment rate of 50 %, the corresponding detachment force, or force of cell adhesion, was determined to be on the order of several nN, consistent with previous reports. The stronger the induced shear flow, the more cells were detached. Further, we employed a preculture time of 8 to 24 h and a PBS incubation time of 0 to 60 min, producing cell adhesion forces that varied from 1.2 to 13 nN. Hence, the developed system can quantify cell adhesion strength over a wide range, possibly offering a fundamental tool for cell-based bioengineering.

Optimizing The Hot-Press Procedure Of High-Temperature Proton Exchange Membrane Fuel Cells For Adhesion Strength And Conductivity

As society considers alternatives to energy systems based on fossil fuel combustion, high-temperature proton exchange membrane (HT-PEM) fuel cells may play an important role in our future energy and transportation portfolio. When compared to low-temperature proton exchange membrane (LT-PEM) fuel cells, HT-PEM technology offers enhanced electrode kinetics, simplified water management, and most notably increased tolerance to fuel impurities such as carbon monoxide. However, compared to more conventional LT-PEM systems, less is known about the durability, performance, and fabrication of HT-PEM materials. Comprised of multiple layers, the membrane electrode assembly (MEA) is a fuel cell’s central component. In a fabrication process similar to LT-PEM MEAs, the proton-conducting membrane, electrodes, gas diffusion layers and sub gaskets are usually hot-pressed together. The parameters surrounding the hot-pressing operation can have a significant impact on the ultimate performance of the fuel cell, in addition to influencing process reliability and repeatability. In the current research, measurements of MEA thickness, impedance, and adhesion strength were obtained for samples over a range of conditions to optimize for the most suitable processing parameters. Testing in this study quantified the effects of hot-press time, temperature and pressure, within ranges of 1-10 minutes, 140 – 200oC, and 7.72 – 92.67 MPa (1120 - 13440 psi), respectively. After hot pressing, the MEA samples were tested for resistance with a 1260a Solartron impedance gain phase analyzer in tandem with a Solartron Ametek 12962a sample holder, and with a Scott internal bond tester for adhesion strength. Based on the results of these tests the optimal hot-press parameters were established, four 25 cm2 MEA were built and tested for performance with post-mortem analysis conducted utilizing scanning electron microscopy (SEM) coupled with energy dispersive X-ray spectroscopy (EDX). These measurements enabled interrogation of potential sources of conductivity loss associated with material layer delamination and/or dehydration of phosphoric acid in the polybenzimidazole (PBI) membrane. In this case, all tests were conducted at 140oC and the resulting material assembly was allowed to cool to room temperature in a nitrogen glove box prior to executing conductivity measurements (i.e., inverse of resistance). Our results have demonstrated that the optimal conditions for MEA hot-pressing for the HT-PEM system are around 170oC and 23.1 MPa for 5 minutes. Each curve in Figure 1 represents the performance of in-house MEAs, prepared using the optimized hot-pressing condition, with variation of platinum-on-carbon content (Pt/C) and total Pt loading. The data presented in Figure 1 demonstrate the effect of varying electrode thickness on MEA performance. Figure 1

Poly(2-Methoxyethyl Acrylate) (PMEA)-Coated Anti-Platelet Adhesive Surfaces to Mimic Native Blood Vessels through HUVECs Attachment, Migration, and Monolayer Formation

Confluent monolayers of human umbilical vein endothelial cells (HUVECs) on a poly(2-methoxyethyl acrylate) (PMEA) antithrombogenic surface play a major role in mimicking the inner surface of native blood vessels. In this study, we extensively investigated the behavior of cell–polymer and cell–cell interactions by measuring adhesion strength using single-cell force spectroscopy. In addition, the attachment and migration of HUVECs on PMEA-analogous substrates were detected, and the migration rate was estimated. Moreover, the bilateral migration of HUVECs between two adjacent surfaces was observed. Furthermore, the outer surface of HUVEC was examined using frequency-modulation atomic force microscopy (FM-AFM). Hydration was found to be an indication of a healthy glycocalyx layer. The results were compared with the hydration states of individual PMEA-analogous polymers to understand the adhesion mechanism between the cells and substrates in the interface region. HUVECs could attach and spread on the PMEA surface with stronger adhesion strength than self-adhesion strength, and migration occurred over the surface of analogue polymers. We confirmed that platelets could not adhere to HUVEC monolayers cultured on the PMEA surface. FM-AFM images revealed a hydration layer on the HUVEC surfaces, indicating the presence of components of the glycocalyx layer in the presence of intermediate water. Our findings show that PMEA can mimic original blood vessels through an antithrombogenic HUVEC monolayer and is thus suitable for the construction of artificial small-diameter blood vessels.

Effects of hydrate inhibitors on the adhesion strengths of sintered hydrate deposits on pipe walls

The effects of hydrate inhibitors on the adhesion of sintered hydrate deposits on pipe walls are still unexplored. Herein, a custom-built adhesion strength measurement apparatus was utilized to quantify the adhesion strengths of sintered cyclopentane (CyC5) hydrate deposits with thermodynamic inhibitors (ethylene glycol, glycerol) and low-dosage inhibitors (dodecylbenzene sulfonic acid (DBSA), sorbitan oleate (Span 80)). It was found that the hydrate adhesion strengths decreased by 69.82%-97.06% and 40.24%-94.36% with the concentration of ethylene glycol and glycerol increased from 2 wt% to 6 wt%, respectively. For DBSA and Span 80, the hydrate adhesion strength increased with concentration less than 0.01 wt% due to the acceleration on hydrate growth. The further increment of concentration leads to a dramatic reduction in adhesion strengths. Furthermore, the relatively large deviations with the predicted strengths led to the discussions of the effects of change in hydrate formation rate, crystal morphology, and also the adaption of the fitting model. Two modified models were proposed to give a better prediction/explanation of the hydrate adhesion with thermodynamic inhibitors and low-dosage inhibitors, respectively. This work provides a fundamental understanding of the adhesion mechanism of hydrate deposits with hydrate inhibitors, which is important in advancing the management of hydrate formation for preventing plugging in pipelines.

Optimizing The Hot-Press Procedure Of High-Temperature Proton Exchange Membrane Fuel Cells For Adhesion Strength And Conductivity

High-temperature proton exchange membrane (HT-PEM) fuel cell systems are under active development for a variety of mobile and stationary power applications. Measurements of membrane-electrode assembly (MEA) thickness, impedance, and adhesion strength were obtained for samples fabricated over ranges of conditions to optimize for the most suitable processing parameters. Testing quantified the effects of hot-press time, temperature, and pressure, over ranges of 1-10 minutes, 140 – 200oC, and 7.72 – 92.67 MPa, respectively. After hot pressing, MEA samples were tested for resistance with a Solartron impedance analyzer, and for adhesion strength with a Scott internal bond tester. From these results, optimal hot-press parameters were established and four 25 cm2 MEAs were fabricated and tested. Post-pressing analysis of MEAs was conducted using scanning electron microscopy coupled with energy dispersive X-ray spectroscopy. Our results demonstrate that the optimal conditions for MEA hot-pressing for the HT-PEM system are around 170oC and 23.1 MPa for 5 minutes.

Functional-gradient coatings of the HfB&lt;sub&gt;2&lt;/sub&gt;–Si&lt;sub&gt;3&lt;/sub&gt;N&lt;sub&gt;4&lt;/sub&gt; system with high wear resistance obtained by supersonic cold gas-dynamic spraying

The results of comprehensive studies of obtaining functionally graded coatings based on HfB2– Si3N4–Zr compositions using the technology of supersonic cold gas-dynamic spraying are presented. Data are given on the measurement of adhesive strength (up to 62 MPa), microhardness (up to 42 GPa) and wear resis- tance (up to 1.2·10–9 mm/km) of the obtained coatings.

Voltage activation of poly (ethylene glycol) diacrylate

Free radical polymerization of acrylate resins may be initiated by light or heat, but a direct electronic mode of activation is missing. Voltage activated free-radical polymerization would address this limitation if suitable electronic initiators are available. Herein, a selection of initiators and electrolytes investigate electronic initiation of diacrylate resins. Electrochemistry and rheometry are combined in a custom electrorheometer towards the evaluation of relevant structure property relationships. Viscoelastic material properties are measured as a function of voltage, chemical initiator, cumulative charge, and electrolyte. Upon cathodic activation, liquid to solid transitions with a maximum shear modulus of 139 kPa is observed while anodic activation failed to initiate gelation. Storage modulus and adhesion strength measurements demonstrate that voltage activation of acrylate resins is feasible, but further improvements in increasing crosslinking kinetics are needed before industrial applicability.

Sliding wear behaviour of thermally sprayed WC–20Cr3C2–7Ni and La2O3composite coatings

In this paper, the sliding wear behaviour of WC–20Cr3C2–7Ni and lanthanum (III) oxide (La2O3) composite coating is investigated. The influence of lanthanum (III) oxide is evaluated by varying its proportion (1, 2 and 3 wt%) in WC–20Cr3C2–7Ni coating material. The high-velocity oxy-fuel (HVOF) technique is used to deposit the coatings on AISI 1020 carbon (C) steel. The mechanical strength and metallurgical quality of the deposit were confirmed by microhardness, adhesive strength and porosity measurements; scanning electron microscopy; and X-ray diffractometry. Further, the sliding wear behaviour of the composite coating is tested on pin-on-disc apparatus with silicon carbide (SiC) as counter material at room temperature. From the investigation, it was found that 2% lanthanum (III) oxide in WC–20Cr3C2–7Ni coating achieved good adhesive strength with minimum wear rate. Addition of lanthanum (III) oxide in WC–20Cr3C2–7Ni prevented the coating from undergoing boundary segregation, crack propagation and grain refinement. Abrasion and ploughing are the common wear mechanisms observed in worn surfaces.

Optimizing The Hot-Press Procedure of High-Temperature Proton Exchange Membrane Fuel Cells for Adhesion Strength and Conductivity

As society considers alternatives to energy systems based on fossil fuel combustion, high-temperature proton exchange membrane (HT-PEM) fuel cells may play an important role in our future energy and transportation portfolio. When compared to low-temperature proton exchange membrane (LT-PEM) fuel cells, HT-PEM technology offers enhanced electrode kinetics, simplified water management, and most notably increased tolerance to fuel impurities such as carbon monoxide. However, compared to more conventional LT-PEM systems, less is known about the durability, performance, and fabrication of HT-PEM materials. Comprised of multiple layers, the membrane electrode assembly (MEA) is a fuel cell’s central component. In a fabrication process similar to LT-PEM MEAs, the proton-conducting membrane, electrodes, gas diffusion layers and sub gaskets are usually hot-pressed together. The parameters surrounding the hot-pressing operation can have a significant impact on the ultimate performance of the fuel cell, in addition to influencing process reliability and repeatability. In the current research, measurements of MEA thickness, impedance, and adhesion strength were obtained for samples over a range of conditions to optimize for the most suitable processing parameters. Testing in this study quantified the effects of hot-press time, temperature and pressure, within ranges of 1-10 minutes, 140 – 200oC, and 7.7 – 92.7 MPa (1120 – 13,400 psi), respectively. After hot pressing, the MEA samples were tested for resistance with a 1260a Solartron impedance gain phase analyzer in tandem with a Solartron Ametek 12962a sample holder, and with a Scott internal bond tester for adhesion strength. Based on the results of these tests the optimal hot-press parameters were established, two 45.2 cm2 MEA were built and tested for performance with post-mortem analysis conducted utilizing scanning electron microscopy (SEM) coupled with energy dispersive X-ray spectroscopy (EDX). These measurements enabled interrogation of potential sources of conductivity loss associated with material layer delamination and/or dehydration of phosphoric acid in the polybenzimidazole (PBI) membrane. Figure 1 shows the effect of hot-pressing time and pressure on the resistance of MEA samples for one representative temperature condition. In this case, all tests were conducted at 140oC and the resulting material assembly was allowed to cool to room temperature in a nitrogen glove box prior to executing resistance measurements (i.e., inverse of conductivity). Each point in Figure 1 represents a single hot-pressed sample, with each sample undergoing three consecutive measurements that were then averaged; standard deviations of triplicate measurements ranged from 0.1 to 3.6%. Our results have demonstrated that the optimal conditions for MEA hot-pressing for the HT-PEM system are around 170oC and 23.1 MPa for 5 minutes. Research is ongoing to evaluate the impact of hot-pressing conditions on fuel cell performance and durability with both hydrogen and reformate fuels. Figure 1 – Selected measurements of HT-PEM resistance with variation of hot-press time and pressure at 140oC Figure 1