Effect Of Long-term Aging Research Articles

Global burden of non-optimal temperature attributable stroke: The long-term trends, population growth and aging effects

Since the 20th century, the world has undergone climate change, population growth and population aging, which may result in alterations in the epidemiology of non-optimal temperature-associated strokes. We employed multiple methodologies and data from the global burden of disease 2019 to unveil the long-term curvilinear trends in strokes attributed to non-optimal temperature and the impact of aging and population growth on its changing epidemiology. From 1990 to 2019, the age-standardized DALYs rate (ASDR) of strokes attributable to low temperature had been decreasing, but from 2016, the continued downward trend in ASDR disappeared and began to remain stable. On the contrary, the ASDR of strokes attributable to high temperature continued to increase. The high socio-demographic index (SDI) region experienced the fastest decreased trend. The disease burden of stroke attributable to low temperature is increased by aging in 178 countries (87.25%), compared with 130 (63.73%) for high temperature. After excluding aging and population growth, the DALY rate for strokes attributed to high temperature was increasing in 87 countries and territories (42.64%). The disease burden of strokes attributed to low temperature is far greater than that of high temperature in absolute figures. However, globally, there is a significant trend toward an increase in strokes attributed to high temperature. Social development has largely offset the burden of strokes attributed to low temperature, but most regions of the world are equally affected by strokes attributed to high temperature. Simultaneously, in the framework of climate change, aging is also largely hindering stroke prevention efforts.

Analysis of static stiffness properties of column-architrave structures of ancient buildings under long term load-natural aging coupling

The column-architrave structures were widely used in the Yingxian wooden pagoda and pagoda has been in service for many years. Over time, it has been subjected to stress and the effects of natural aging. In order to analysis the ability of the structures to resist deformation under specific static excitation, a study of the static stiffness properties of column-architrave structures in ancient buildings considering long term load-natural aging coupling was carried out. Based on the Gerhards model, a strength degradation model has been developed for column elements and architrave elements, taking into account long-term loading and natural aging effects; By constructing a regular model and a realistic model, the deformation of the regular model under long term self weight load and the deformation of the realistic model under long term self weight load and aging are simulated by finite element model; The relationship between deformation values and static stiffness as a function of time is investigated through multiple points of the column-architrave structures, and the reliability of the proposed model is verified by extracting and comparing data from the automated real-time 3D monitoring system of the wooden pagoda. The results show that the numerical simulations of both models show that the middle of the architrave is more easily deformed than the mortise and tenon joint structures; The deformation resistance of the realistic model is lower than the deformation resistance of the regular model, and the natural aging effect has a non-negligible deterioration effect on the deformation of the column-architrave structures; For the column and architrave elements, they are likely to become unstable at 3330 AD and 3543 AD respectively, which means that after 1307 and 1520 years, the static stiffness of both elements tends to decrease with time in service, with the decrease in static stiffness of the architrave elements being less than that of the column elements.

Influence of ageing temperature on the tribological characteristics of LM25/Al2O3/SiC hybrid metal matrix composite for lightweight applications

The demand for hybrid composites has lately increased due to their extraordinary qualities, which include unique mechanical, tribological, and physical capabilities not found in other materials. These composites improve performance and utility by mixing different reinforcing components, making them highly sought after. However, there is a study gap on the effects of long-term ageing on the tribological characteristics of LM25 (Al–6.6Si–0.2Mg)/Al2O3/SiC metal matrix composites (MMCs). As a result, extensive studies on the influence of ageing temperature on the tribological properties of LM25/Al2O3/SiC MMCs via long-term ageing effects still need to be included. Therefore, this study investigated the metallurgical and hardness properties of stir-cast LM25 alloy reinforced with Al2O3 and SiC particulates with varying ageing temperatures. Furthermore, dry sliding wear behaviour is also examined. The investigation concluded that adding micron-sized Al2O3 and SiC particles to LM25 improves hardness and tribological properties. As the ageing temperature increased, the eutectic particles became coarser. Furthermore, the result illustrates that the coefficient of friction (COF) values also enhanced with wear rates. Higher loads increased the wear rate and COF, whereas higher sliding speeds decreased the COF and wear rate.

Short-term and long-term aging effect of the rejuvenation on RAP binder and mixes for sustainable pavement construction

• Physical and rheological properties of rejuvenated RAP and virgin binder compared. • Determination of optimum dosage range of the rejuvenator. • Performance evaluation rejuvenated RAP mixes. This investigation analyzes the usefulness of Mahua oil (M-oil) in reclaimed asphalt pavement (RAP) binder which simulates the short-term and long-term aging behavior of asphalt. As the inclusion of a higher amount of the RAP in the bituminous mix is susceptible to fatigue and thermal cracking, the use of a rejuvenator is a suitable option that can reinstitute the properties of the virgin binder. Different percentages of M-oil such as 1%, 2%, 3%, 4%, 5%, and 6% added to the short-term and long-term aged binder. Blended rejuvenated binders were evaluated through various physical properties. It was noticed that the inclusion of a rejuvenator increases the penetration, ductility, and flash point and reduces the softening point, and viscosity. Rheological properties conclude that rejuvenating short-term and long-term aged binder is feasible and can be considered an effective way to recycle the RAP binder. Further, rejuvenated (5% and 6% M-oil by weight of aged binder which is the optimum dosage) mixes were prepared with RAP mixture for short-term and long-term aging conditions to study the mechanical properties, i.e., moisture sensitivity and rutting. Finally, it was concluded that 5% M-oil successfully rejuvenated the RAP mixes in long-term aging conditions.

Long-term water aging effects on the durability of alkali-treated bamboo fiber reinforced composite

Long-term water aging effects on the durability of alkali-treated bamboo fiber reinforced composite

Influence of Binary Blended Fillers on Long-Term Aging Effect and Rutting Performance of Warm-Mix Asphalt

Influence of Binary Blended Fillers on Long-Term Aging Effect and Rutting Performance of Warm-Mix Asphalt

Evaluation of Aging and Moisture Damage Potential of Warm Mix Asphalt Incorporating a Synthetic Wax Additive

This paper presents the effects of a warm mix additive on the moisture damage of warm mix asphalt (WMA). Asphalt mixtures were made using different WMA contents (0, 2 and 3%) at different compaction temperatures. Aging properties were studied from the effects of artificial long-term aging on resilient modulus (MR) and indirect tensile strength (ITS) of WMAs. Moisture damage was investigated in term of tensile strength ratio (TSR) of unaged and aged specimens conditioned in one and three cycles of freezing and thawing. The results showed that the aging significant affected the MR and ITS of WMA. The additive content increased with air voids but in contrary with the bulk density. Hence, the use of higher additive content can be more beneficial in terms of resilient modulus. Decreasing compaction temperature could significantly decrease the ITS while the TSR of WMA reduced as compaction temperature decreased. From moisture damage tests, the TSR of aged samples was found to be lower than that of unaged samples

Effects of thermal aging at 873 K on the impact properties of an ODS ferritic steel

This investigation presents the effects of long-term thermal aging on the impact properties of an ODS reduced activation ferritic steel. The ODS ferritic steel, with composition Fe–14Cr–2W–0.4Ti–0.3Y2O3 (wt. %), was manufactured by mechanical alloying, compacted by hot isostatic pressing and hot cross rolled. A 1273 K annealing treatment was applied, followed by thermal aging at 873 K for 2000 h in Ar, to evaluate the thermal stability of the alloy. Charpy impact testing was performed from 77 to 473 K to investigate the mechanical response of the material under dynamic loads. The ductile-to-brittle transition temperature (DBTT) showed a slight increase with values of 255 ± 12 K before aging, and 270 ± 20 K after aging. The aging treatment softened the steep character of the Charpy impact curves inducing a wider transition regime with mixed brittle and ductile fracture mechanisms. This behavior was confirmed by the analysis of Force vs. Displacement Charpy curves and fractographic observations. Hot cross rolling induced a crack divider geometry and secondary cracks formation by delamination. Ductile fracture was less evident after aging due to the redistribution and transformation of Cr-W-rich precipitates along grain boundaries. Electron Backscattered Diffraction highlighted the features of transgranular brittle cracks at temperatures below the DBTT and showed misoriented and deformed regions near the fracture surface at temperatures above the DBTT.

Marginal fit and fracture resistance of polyetheretherketone, zirconia, and titanium implant-supported prosthesis frameworks for a partially edentulous arch after thermomechanical aging

Although polyetheretherketone (PEEK) and zirconia (Zir) have been used as implant-supported prosthesis (ISP) frameworks, the long-term effects of thermomechanical aging on the marginal fit and fracture resistance of PEEK and Zir ISP frameworks with titanium (Ti) bases for patients with a partially edentulous arch are not clear. The purpose of this in vitro study was to determine the marginal fit and fracture resistance of PEEK and Zir ISP frameworks with Ti bases and Ti ISP frameworks for partially edentulous arches after aging. A total of 30 ISP epoxy resin casts were obtained from a typodont with 1 straight implant (Nobel Biocare) in the mandibular right canine region and 1 implant with a 30-degree distal tilt in the mandibular right first molar region. All frameworks (n=10) were fabricated on their own epoxy resin cast with multiunit abutment replicas by using a computer-aided design and computer-aided manufacturing system (exocad-Yenadent). The PEEK and Zir frameworks were fabricated with Ti-bases. Primer (MKZ) and resin cement (DTK adhesive) were used to cement the frameworks to the Ti-bases under a static load of 10N. After thermomechanical aging (1.2×106 cycles, 120N, 5°C-55°C), marginal gaps between the Ti-bases and cemented frameworks and vertical and passive fits between the Ti-bases and framework and multi-unit abutments were measured by using a stereomicroscope (Euromex) at ×100 magnification. Fracture resistances and types were then determined by using a universal test machine and a stereomicroscope at ×40 magnification. Data were analyzed by using 1-way analysis of variance (ANOVA) and the Tukey HSD and Fisher-Freeman-Halton tests (α=.05). The marginal gaps of the PEEK and Zir frameworks were respectively 83.5 ±27.1 and 81.8 ±17.8µm. PEEK (23.7 ±4.6) and Zir (32.9 ±8.7) had a better vertical fit (µm) than Ti (52.5 ±10.6) (P<.001). Zir (49.3 ±16.2) (P<.001) and PEEK (70.9 ±19.6) (P>.05) frameworks had better passive fit (µm) than Ti (91.3 ±24.2). Ti had the highest mean fracture resistance (N) (14800.2 ±3442.3) followed by Zir (7318.7 ±1385.1) and PEEK (3448.9 ±486.6) (P<.001). Fracture types were different in different groups (P<.001). The PEEK and Zir frameworks with Ti baseshad better vertical and passive fit than the Ti frameworks. All ISP frameworks represented mean marginal fit below 92µm and withstood physiologic occlusal forces after thermomechanical aging.

Evaluation of the impact of long-term aging on fracture properties of warm mix asphalt (WMA) with high RAP contents

This study aimed to investigate the effects of long-term aging on the fracture characteristics of Warm Mix Asphalt (WMA) containing Reclaimed Asphalt Pavement (RAP). To this end, various RAP contents (0, 50, 75, and 100%) and one WMA additive (Zycotherm) were used. The Semi-Circular Bending (SCB) fracture test was conducted at intermediate temperature and fracture parameters, including the fracture force, fracture toughness, strain energy, J-integral, stiffness, and flexibility index were measured to identify the impact of aging and RAP addition on different fracture properties of WMA mixtures. To remedy the problem concerning the amorphous trend of fracture properties over the service time and intersecting the curves of fracture parameters versus service time, the area beneath the fracture parameter was employed as a reliable index for comparing different mixes. Then, summations of the area of all fracture parameters versus service time for various mixtures with different RAP content were identified as the overall fracture resistance of each mixture. Finally, an analysis of variance (ANOVA) was determined to statistically assess the results of the SCB fracture test. This study highlights the importance of considering long-term aging effects on WMA mixtures containing RAP and the potential benefits of using high RAP content in flexible pavements. Overall, this research can help agencies make a more precise decision regarding the consequences of high RAP content on the long-term performance of asphalt pavements.

Effect of long-term natural aging on the microstructural characteristics of an extruded WE54 alloy

The microstructure and the corresponding crystallographic texture of the as-extruded WE54 alloy after natural aging for 11 years at room temperature have been characterized by the Electron backscatter diffraction (EBSD) technique. Before natural aging, the as-extruded WE54 exhibited equiaxed microstructure with a strong splitting basal texture and the presence of second particles along the extrusion direction (ED). Unexpectedly, long-term aging led to the formation of elongated deformed grains along ED having {11–20}<10-10> and {0001}<10-10> orientations with a partial development of fine static recrystallized grains by continuous and discontinuous mechanisms. It is believed that the origin of such grain structure development is the residual stored strain during the extrusion processing and the strain field induced from the solute Nd and Y atoms diffusion through the long-term natural aging. Artificial aging at 400 °C for 60 min demonstrated that the elongated deformed grains disappeared and left behind a heterogeneous recrystallized microstructure with a weak basal texture.

Effect of Long-Term Aging on Fatigue and Thermal Cracking Performance of Polyphosphoric Acid and Styrene-Butadiene-Styrene-Modified Bio-Blend Bitumen.

Polyphosphoric acid (PPA) and styrene-butadiene-styrene (SBS) were adopted to produce PPA-SBS-modified bio-blend bitumen, which achieved excellent mechanical performance. However, its long-range performance, such as the fatigue and thermal cracking behavior under long-term thermal oxidation, is not well understood. Therefore, a pressure aging vessel (PAV) system was applied to simulate the aging behavior of the bitumen under the action of thermal oxidation. Then, a linear amplitude sweep (LAS) test combined with a viscoelastic continuum damage (VECD) model was applied to investigate the fatigue properties of the bitumen. Moreover, a bending beam rheometer (BBR) test was conducted to evaluate the thermal cracking resistance of the bitumen before and after PAV aging. Meanwhile, an atomic force microscope (AFM) was applied to observe the microscopic topography. The results show that the original compound-modified bitumen can bear more fatigue damage than that of the control bitumen at the failure point, and it also has excellent fatigue resistance at 2.5%, 5%, 7.5%, and 10% applied strain. Moreover, the VECD model can accurately predict the fatigue life of the bitumen under different applied strains. The variation ratio of stiffness modulus for the compound-modified bitumen is below that of the control bitumen after PAV aging, so it shows a better anti-aging performance. Finally, the AFM test shows that PPA and bio-bitumen decrease the heterogeneity of the bitumen, reducing the difference between phases.

Predicting adsorption capacity of pharmaceuticals and personal care products on long-term aged microplastics using machine learning

We investigated the adsorption mechanism of 66 coexisting pharmaceuticals and personal care products (PPCPs) on microplastics treated with potassium persulfate, potassium hydroxide, and Fenton reagent for 54, 110, and 500 days. The total adsorption capacity (qe) of 66 PPCPs on 15 original microplastics was 171.8 – 1043.7 μg/g, far below that of 177 long-term aged microplastics (7114.0 – 13,114.4 μg/g). Around 69.8% of qe was primarily influenced by the total energy, energy of the highest occupied molecular orbital, and energy gap of PPCPs, calculated using the B3LYP/6–31 G* level. Furthermore, 111 aged microplastics exhibited similar total qe values. Additionally, we developed predictive models based on attenuated total reflectance Fourier transform infrared spectroscopy to predict the individual and total qe on 192 microplastics. These models, including the maximal information coefficient and gradient boosting decision tree regression, exhibited high accuracy with Rtraining2 values of 0.9772 and 0.9661, respectively, and p-values below 0.001. Spectroscopic analysis and machine learning models highlighted surface functional group alterations and the importance of the 1528–1700 cm−1 spectral region and carbon skeleton in the adsorption process. In summary, our findings contribute to understanding the adsorption of PPCPs on microplastics, particularly in the context of long-term aging effects.

Long-term natural-aging-induced alleviation of attenuation of artificial-aging hardenability in an Al-5Mg-3Zn-1Cu (wt.%) alloy

Effects of long-term natural aging (NA, 2400 h) on the artificial aging (AA) responses of Al-5Mg-3Zn-1Cu alloy at various temperatures (120–175 °C) were scrutinized. The results show that the hardenability of the alloy without NA (NA-free) deteriorates seriously at high AA temperatures (>150 °C). Such decay of AA hardenability is primarily induced by the larger and sparser intragranular precipitates and is also associated with the wide precipitation-free zone. Compared with NA-free alloy, long-term natural pre-aging improves the nucleation conditions in the early stage of subsequent AA, thus preventing these unfavorable microstructures and thereby mitigating the decay of hardening potential.

Effects of Long-Term Aging on Structure Evolution and Stress Rupture Property of DD6 Single-Crystal Superalloy

For China’s second-generation aero-engine blade DD6 single-crystal high-temperature alloy, the standard solution-treated test rods were subjected to long-term aging experiments (1290 °C, 1 h + 1300 °C, 2 h + 1315 °C, 4 h air cooling + 1120 °C, 4 h air cooling + 870 °C, 32 h air cooling) at 980 °C for 1000 h, 5000 h, and 7500 h, and the effects of different long-term aging times on the organization evolution, phase precipitation morphology, high-temperature mechanical properties, and endurance performance of the alloy were studied. The results show that with the increase of aging time, the γ′ phase coarsens, joins along the &lt;100&gt; and &lt;010&gt; directions, and merges to form irregularly shaped directional growth and rafting. The endurance life shows a decreasing trend; at 980 °C/243 MPa, 980 °C/270 MPa, 980 °C/309 MPa for the alloys after 5000 h aging, the enduring life decreased by 47.97%, 70.98%, and 76.75%, and 81.25%, 73.18%, and 87.00% after 7500 h aging, respectively. The tensile strength of the alloy at 760 °C first decreases and then increases, with a minimum value at 5000 h; there is a gradual increase in elongation; there is a gradual decrease in tensile strength at 980 °C; and there is first an increase and then decrease in elongation, with a maximum value at 1000 h. This is due to the diffusion phenomenon of the elements in the alloy after 5000 h aging, the emergence of W-rich, Re-, Mo-, and Ni-poor phenomena, and the transformation of the μ-phase from needle-like to rod-like and block-like.

Accelerated physical aging of four PET copolyesters: Enthalpy relaxation and yield behaviour

Assessing suitability of amorphous polymers in durable products requires understanding of long-term effects of physical aging on the material properties. This work shows four polyesters with varying diol composition (poly(ethylene-co-1,4-cyclohexylenedimethylene terephthalate) (PETG1 and PETG2 with ∼30 and ∼60% 1,4-cyclohexylenedimethylene (CHDM), respectively), poly(ethylene-co-2,2,4,4-tetramethyl-1,3-cyclobutanediol terephthalate) (PETT) with ∼30% 2,2,4,4-tetramethyl-1,3-cyclobutanediol (TMCD) and poly(1,4-cyclohexylenedimethylene-co-2,2,4,4-tetramethyl-1,3-cyclobutanediol terephthalate) (PCTT) with ∼80% CHDM and ∼20% TMCD) exposed to thermal treatment at 20, 30 and 40 °C below their respective glass transition temperatures for up to 504 h to accelerate physical aging. The enthalpy relaxation was investigated by differential scanning calorimetry and compared to mechanical changes manifested as tensile yield strength increase. The physical aging rates were found to depend on both chemical structure and composition of CHDM and TMCD segments, where the introduction of TMCD inhibited physical aging. Arrhenius and Vogel-Fulcher-Tamman models were used to fit horizontal shift factors and evaluate the time and temperature dependencies for each polyester. From this study, the two models showed no significant differences in ability to describe the effects of physical aging. The Arrhenius activation energies, Ea, were all in the range 118–244 kJ mol−1, were both PETG1 and PETG2 showed no significant difference between Ea for enthalpy relaxation and yield strength increase, whereas PETT and PCTT showed ∼19 and ∼107% difference between the two, respectively, suggesting that the relationship between the two phenomena is not independent of chemical structure. The difference between the activation energies suggests that the time scales for physical aging are different when observed as enthalpy relaxation and yield strength.

Embryonic factors mediate the maternal age-induced programming of offspring postnatal behavior in mice†.

Advanced maternal age is associated with adverse pregnancy and offspring outcomes, including neurodevelopmental disorders. While age-related oocyte and embryonic abnormalities may underlie this association, the aged maternal uterine environment also plays an important role in offspring development and survival. The aim of this study was to evaluate the contribution of maternal age-related embryonic and uterine factors on pregnancy and offspring behavior, by using a model of reciprocal embryo transfer between old and young female mice. Pregnancies were obtained by transferring embryos collected from either old (9-14months) or young (3-4months) C57BL/6J female mice to either young or old recipients. The results showed that embryos from old and young donors have comparable developmental potential when transferred to young recipients, whereas no pregnancies were obtained by transferring embryos of young females to old recipients. Moreover, the offspring conceived by aged females displayed altered ultrasonic vocalization and learning skills compared to the progeny of young females, even though they were both prenatally and postnatally fostered by young recipients. These results indicate that maternal factors mostly determine the occurrence of age-related pregnancy complications, whereas the long-term effects of maternal aging on the offspring's behavior could be already established at pre-implantation stages and depend on embryonic factors.

A Microstructure-Based Mechanistic Approach to Detect Degeneration Effects on Potential Damage Zones and Morphology of Young and Old Human Intervertebral Discs.

There is an increasing demand to develop predictive medicine through the creation of predictive models and digital twins of the different body organs. To obtain accurate predictions, real local microstructure, morphology changes and their accompanying physiological degenerative effects must be taken into account. In this article, we present a numerical model to estimate the long-term aging effect on the human intervertebral disc response by means of a microstructure-based mechanistic approach. It allows to monitor in-silico the variations in disc geometry and local mechanical fields induced by age-dependent long-term microstructure changes. Both lamellar and interlamellar zones of the disc annulus fibrosus are constitutively represented by considering the main underlying microstructure features in terms of proteoglycans network viscoelasticity, collagen network elasticity (along with content and orientation) and chemical-induced fluid transfer. With age,anoticeable increase in shear strain is especially observed in the posterior and lateral posterior regions of the annulus which is in correlation with the high vulnerability of elderly people to back problems and posterior disc hernia. Important insights about the relation between age-dependent microstructure features, disc mechanics and disc damage are revealed using the present approach. These numerical observations are hardly obtainable using current experimental technologies whichmakes our numerical tool useful for patient-specific long-term predictions.

Laboratory Investigation of Storage Stability and Aging Resistance of Slightly SBS-Modified Bitumen Binders

Slightly SBS-modified bitumen binders have been applied for the asphalt concrete impermeable layer of pumped storage power stations (PSPSs) in China. However, the storage stability and aging resistance of slightly SBS-modified bitumen are big concerns. In this study, three different types of slightly SBS-modified bitumen binders were evaluated by using a commonly used virgin bitumen and a normal SBS polymer-modified bitumen as references. All of the bitumen binders were subjected to short-term and long-term aging that were simulated by using a 5 h and 24 h thin film oven test (TFOT), respectively. A Fourier transform infrared (FTIR) spectroscopy test, storage stability test, dynamic shear rheological test, stress relaxation test, and direct tensile (DT) test were carried out to obtain insight into the storage stability and aging resistance. FTIR analysis indicated that slightly SBS modified bitumen exhibited serious aging of base bitumen together with higher polymer degradation. The aging indexes obtained from the carbonyl index and the polybutadiene (PB) index can well rank the aging resistance. Slightly SBS-modified bitumen binders had excellent storage stability, and even after a long-term period of 7 days of storage, the complex modulus and phase angle remained fairly constant. The rheological master curves were constructed to investigate the effects of short-term and long-term aging. Slightly modified bitumen binders were well identified by the plateau of the phase angle master curves. The aging resistance was well distinguished by the deviation of the complex modulus master curve using unaged bitumen as a baseline. It was found that three types of slightly SBS-modified bitumen binders exhibited inconsistent aging resistance in terms of rheological aging index. The relative change of the initial instantaneous modulus and the modulus relaxation rate was able to explain the relaxation properties. With respect to the direct tensile test, the increase in stiffness modulus and the loss of ultimate tensile strain can be used to evaluate the susceptibility of bitumen aging. An attempt was made to establish the relationship of the aging index between FTIR analysis, rheological properties, and low-temperature performance. It was found that the relationship among these aging indexes was weak. In general, slightly SBS modified bitumen should be well designed to obtain good aging resistance and low-temperature performance. Highly modified bitumen is foreseen to be promising in the case of extremely low temperatures and long-term durability.

Investigation of the Wet and Thermal Conditions Effect on the Micro-Scale Characteristics of Interfacial Transition Zone of Porous Asphalt Mixture

Complex environmental factors can significantly influence the micro-properties of porous asphalt (PA) mixture. Therefore, the effects of short-term and long-term thermal aging and moisture immersion on the micromechanics properties, micro-morphology, and chemical element distributions of the interfacial transition zone (ITZ) of PA mixture were studied to reveal the mechanisms by which environmental degradation impact performance by means of nanoindentation (NI), backscattering scanning electron microscope (BSEM), and energy-dispersive X-ray spectroscopy (EDS) analysis techniques. The results show that the ITZ is not the softest part of the PA mixture, and the order of modulus is aggregate &gt; ITZ &gt; asphalt mastic. ITZ thickness is about 10–20 μm. Thermal aging has negligible effect on the width of ITZ. With increasing aging degree, the asphalt mastic and ITZ modulus increase, while water damage reduces the modulus of ITZ and slightly increases the width of ITZ. Thermal aging has little effect on the morphology of ITZ, while water damage will lead to microcracks and micropores in ITZ. Compared with thermal aging, water damage has a greater effect on the morphology of ITZ and leads to softening of the interfacial transition zone and asphalt mastic phase. The width of ITZ obtained by EDS line scanning is basically consistent with that of nanoindentation. Overall, external environmental factors have a more significant effect on the mechanical properties than the micro-morphology of ITZ. The outcomes of this research provide a better understanding of the impact of the service environment on the microscopic characteristics of PA mixture.