Irregular Cracks Research Articles

Study on the influence of indentation depths on the fracture characterization and acoustic emission characteristics of minerals in granite using nanoindentation

To investigate the intrinsic mechanisms of rock rupture at the mesoscale, this study employed nanoindentation tests on three primary minerals in granite at various indentation depths. Concurrently, rupture signals generated throughout the indentation process were recorded using the PCI-2 acoustic emission (AE) system. The results revealed that crack lengths in quartz and feldspar increased with indentation depth, whereas mica exhibited negligible radial cracking, showing only short, irregular cracks around the edges of the indentation marks. As indentation depth increased, the intensity of plastic deformation at the indentation point also increased, leading to a gradual reduction in fracture toughness and a corresponding rise in AE amplitude and energy. All three minerals generally showed a higher proportion of high-frequency signals compared to low-frequency signals, with the distribution characteristics of these signals being significantly influenced by the mineral properties. Quartz and feldspar exhibited relatively balanced frequency distributions, while mica had a higher proportion of high-frequency signals. At different indentation depths, most signals displayed characteristics of higher RA values and lower AF values, indicating that, at the mesoscale, the rupture modes of the three major minerals in granite are predominantly shear failures.

Investigation into the mechanism of ignition of magnesium alloy plates by high-temperature molten droplet

The ignition and spread of magnesium alloy fires are mainly attributed to the ignition of high-temperature molten metal droplets, but the underlying ignition mechanism remains unclear. This study addresses this knowledge gap by employing metallic aluminum and copper particles heated to temperatures over 1200 °C. Systematically, these heated particles were released at a fixed rate onto a magnesium alloy plate located inside a controlled heating furnace that maintained a constant temperature of 500 °C. Experimental results show that whether there are irregular pores and cracks in the resulting molten product can be used as a criterion for judging whether the magnesium alloy sample ignites. Furthermore, it is worth noting that molten copper droplets of the same size exhibit a higher heat-carrying capacity than their aluminum counterparts when both are heated to the same temperature. In addition, this study expanded the research scope through numerical simulation and analysis, using the PATO (Porous-Material Analysis Toolbox) solver to clarify the transient heat conduction process between the high-temperature droplet and the magnesium alloy plate. Simulations show that heat transfer upon droplet impact is primarily longitudinal, directed toward the base of the material. This results in a significantly higher temperature in the center of the affected magnesium alloy plate than at its periphery. In summary, this study helps to improve the understanding of the dangers of high-temperature molten droplets, and it is of great significance to investigate fire accidents caused by high-temperature molten droplets.

Full-scale field test of early-age behaviour of partially continuous reinforced concrete pavement

To address the damage characteristics and deficiencies of the existing continuously reinforced concrete pavement (CRCP), which are the high construction cost and irregular crack distribution patterns, a concrete pavement structure called partially continuous reinforced concrete pavement (PCRCP) is proposed. In this paper, the early-age (28 days, without traffic) behaviour of PCRCP subjected to environmental loading is investigated. To this end, full-scale field tests were carried out in Xiangjiagou Tunnel, Shanxi Province, China. Testing results showed that the PCRCP test section with the partial continuous reinforcement length of 100 cm and active crack spacing of 5 m can provide better early-age performance and lower initial construction cost in this study. The PCRCP test section with the active crack control method has a uniform crack distribution pattern with narrow width compared to the CRCP test section. The results of this study would provide data support and reference for the rational design of PCRCP.

Enhancing flexible electronics: Unveiling the role of strain rate in the performance of molybdenum-coated PET films

This work analyzes the mechanical and electrical properties of molybdenum (Mo) thin films at 100 and 200 nm thicknesses under different strain and strain rate circumstances. The study examines Mo film deposition by RF magnetron sputtering on PET substrates and their mechanical stress behavior. The investigation reveals distinct patterns of crack initiation and propagation, where primary cracks predominantly appear perpendicular to the direction of applied strain, and secondary cracks develop due to stress redistribution, displaying a complex interplay between film thickness, strain rate, and crack morphology. A key finding of this study is the observation of more advanced and irregular crack patterns in thicker films (200 nm) subjected to higher strain rates (1000 mm/min), suggesting a heightened sensitivity to mechanical stress and a more chaotic fracture process compared to thinner films or those under lower strain rates. Additionally, instances of film edge delamination, particularly under high strain conditions, highlight the challenges in maintaining film-substrate adhesion and integrity under extreme mechanical deformation. The research provides critical insights into the mechanical robustness and electrical performance of Mo thin films, emphasizing the influence of microstructural properties, deposition parameters, and external stressors on their applicability in high-tech industries. The findings underscore the importance of optimizing deposition techniques and understanding material behavior under stress to enhance the durability and reliability of Mo thin films in practical applications, ranging from semiconductor devices to photovoltaic systems.

3D analysis of crack propagation in nuclear graphite using DVC coupled with finite element analysis

The initiation and propagation of cracks within nuclear graphite components compromise the lifespan of advanced gas-cooled reactors and even lead to safety incidents. A thorough understanding of fracture properties in nuclear graphite is crucial for the effective management and design of graphite structural components. In this work, an in-situ test of a double cleavage drilled compression (DCDC) specimen was conducted using X-ray tomographic imaging to fully analyze the 3D crack propagation behavior in IG-11 nuclear graphite. “Subvolume Splitting” digital volume correlation (SS-DVC) was employed to accurately quantify the displacement fields surrounding the crack. The entire 3D crack propagation and crack surface around the crack front were precisely captured through 3D imaging processing of the gray level residual (GLR) field. Additionally, crack opening displacements (CODs) and stress intensity factors (SIFs) were determined using finite element (FE) analysis with extended finite element method (XFEM). Experimental results indicate that although mode I crack remains predominant throughout the whole process, complex crack propagation exists around the crack front. The utilization of irregular crack surfaces in FE analysis helps to obtain refined displacement fields and accurate SIFs of the crack front. This work provides comprehensive insights into crack propagation and reveals the influence of complex crack morphology on SIF calculations, facilitating accurate prediction of structural integrity and rational design of graphite components.

Comparison of Optical Properties and Fracture Loads of Multilayer Monolithic Zirconia Crowns with Different Yttria Levels.

Multilayer monolithic zirconia, which incorporates polychromatic layers that mimic natural tooth gradients, offers enhanced aesthetics and functionality while reducing debonding risks and improving fabrication efficiency. However, uncertainties remain regarding the fracture characteristics of multilayer monolithic zirconia crowns under occlusal loading, whether composed of uniform or combined yttria levels. The current study investigated how variations in yttria levels and thicknesses affected the optical properties and fracture loads of multilayer monolithic zirconia. Samples of multilayer monolithic zirconia in the Vita A1 shade were used, while employing 3Y (SZ) and 4Y + 5Y (AZ) yttria levels. The optical properties, including the color difference (ΔEWS) and translucency parameters (TP00), were measured using a digital colorimeter. The fracture loads were analyzed using a universal testing machine, and fractured surfaces were examined under a stereomicroscope. Statistical analyses assessed the impacts of the yttria levels and sample thicknesses on the optical properties. The ΔEWS values of SZ ranged 3.6 to 4.0, while for AZ, ΔEWS at 0.5 mm was 3.9 and <2.6 for other thicknesses. The TP00 values decreased with an increased thickness, with AZ generally exhibiting greater translucency than SZ. In the fracture load investigations, SZ (>1600 N) generally exceeded AZ (>1260 N), with fracture loads notably increasing with thickness, particularly for premolars (SZ > 3270 N, AZ > 2257 N). SZ predominantly exhibited partial and complete fractures, whereas AZ showed fewer non-fracture categorizations. Complete fractures began with dense, irregular cracks that extended outward to reveal smooth surfaces, while premolars subjected to higher loads exhibited concentric ripple-like structures. Partial fractures revealed radial textures indicative of areas of stress concentration. In summary, higher yttria levels were correlated with increased translucency, while variations in the fracture loads primarily stemmed from differences in the tooth position or thickness. Overall, multilayer monolithic zirconia incorporating combined yttria levels of 4Y + 5Y (AZ) offered high translucency, precise color matching, and substantial fracture resistance, rendering it highly suitable for aesthetic and functional dental applications.

A Road Crack Segmentation Method Based on Transformer and Multi-Scale Feature Fusion

To ensure the safety of vehicle travel, the maintenance of road infrastructure has become increasingly critical, with efficient and accurate detection techniques for road cracks emerging as a key research focus in the industry. The development of deep learning technologies has shown tremendous potential in improving the efficiency of road crack detection. While convolutional neural networks have proven effective in most semantic segmentation tasks, overcoming their limitations in road crack segmentation remains a challenge. To address this, this paper proposes a novel road crack segmentation network that leverages the powerful spatial feature modeling capabilities of Swin Transformer and the Encoder–Decoder architecture of DeepLabv3+. Additionally, the incorporation of a multi-scale coding module and attention mechanism enhances the network’s ability to densely fuse multi-scale features and expand the receptive field, thereby improving the integration of information from feature maps. Performance comparisons with current mainstream semantic segmentation models on crack datasets demonstrate that the proposed model achieves the best results, with an MIoU of 81.06%, Precision of 79.95%, and F1-score of 77.56%. The experimental results further highlight the model’s superior ability in identifying complex and irregular cracks and extracting contours, providing guidance for future applications in this field.

W-rich zircons from the granite in the Hukeng tungsten deposit, South China: Genesis and exploration significance

South China is endowed with copious hydrothermal tungsten ore deposits, which are generally suggested to be associated with highly fractionated granites. However, the mechanism of tungsten enrichment and mineralization during magmatic-hydrothermal processes is not clear. Here, we clearly identified W-rich zircons (up to several thousand ppm) from the granite in the Hukeng tungsten deposit in South China. W-rich zircons are generally dark in cathodoluminescence images with irregular cracks, cavities and blurry oscillatory zones. They also show high contents of U, Nb, REEs, and high W/Gd ratios, which are not possible to be produced only by magma differentiation. Raman spectra of zircons indicate that these W-rich zircons have experienced different degrees of metamictization. Thus, these W-rich zircons should be crystallized from the late magma and subsequently altered by W-rich magmatic-hydrothermal fluids. W-rich zircons record the activity of W-rich ore-forming fluids which were exsolved from the granitic magma. We suggested that the W/Gd ratios of > 0.2 of zircons can be used as an indicator to estimate the W mineralization potential of a granite. This study provides a new pathway for using zircon to record tungsten mineralization processes and to guide tungsten ore prospecting.

Formation cause and oxidation behaviour of surface crack on the hot-rolled thick plate of high strength low alloy steel

The formation causes and oxidation behaviour of two types of small-sized and irregular morphological surface cracks on S355 hot-rolled thick plate were investigated. The study employed surface pickling, microstructure analysis and inclusion observation to characterise the cracks. It was observed that the surface morphology of two types of cracks exhibited similarities, while their subsurface morphology differed. The Type-A cracks displayed a bulge shape with a rounded tail, while the Type-B cracks had a V-shaped morphology with a slender tail. The Type-A cracks predominantly consisted of FeO. The surface part of the Type-B cracks contained unusual large-sized carbon particles and Al2O3 inclusions, and the iron oxides within the subsurface part followed the sequence of FeO–Fe2O3–Fe from the centre of the cracks to the steel matrix. It was observed that the Type-A cracks originated from subsurface bubbles in the continuous casting slab, which deformed and developed into surface cracks during the rolling process. The iron oxide inside these cracks was formed through a single oxidation process, and the bulge shape in the subsurface part was a distinguishing characteristic. The Type-B cracks were attributed to surface microcracks on the continuous casting slab, which were linked to the presence of unusual large-sized inclusions. The iron oxides within these cracks underwent two oxidation processes. The subsurface morphology and oxide characteristics are the significant features to identify these small-sized and irregular morphological cracks.

Enhancing Encapsulation Efficiency of Chavir Essential Oil via Enzymatic Hydrolysis and Ultrasonication of Whey Protein Concentrate-Maltodextrin.

This study focused on the characterization of emulsions and microparticles encapsulating Chavir essential oil (EO) by application of modified whey protein concentrate-maltodextrin (WPC-MD). Different physical, chemical, morphological, thermal, and antioxidant properties and release behavior of spray-dried microparticles were assessed. Antioxidant, solubility, emulsifying, and foaming activities of modified WPC were increased compared to those of primary material. The results indicated that the particle size distribution varied depending on the type of carriers used, with the smallest particles formed by hydrolyzed WPC (HWPC). Binary blends of modified WPC-MD led to improved particle sizes. The spray-drying yield ranged from 64.1% to 85.0%, with higher yields observed for blends of MD with sonicated WPC (UWPC). Microparticles prepared from primary WPC showed irregular and wrinkled surfaces with indentations and pores, indicating a less uniform morphology. The UWPC as a wall material led to microparticles with increased small cracks and holes on their surface. However, HWPC negatively affected the integrity of the microparticles, resulting in broken particles with irregular shapes and surface cracks, indicating poor microcapsule formation. Encapsulating EO using WPC-MD increased the thermal stability of EO significantly, enhancing the degradation temperature of EO by 2 to 2.5-fold. The application of primary WPC (alone or in combination with MD) as wall materials produced particles with the lowest antioxidant properties because the EO cannot migrate to the surface of the particles. Enzymatic hydrolysis of WPC negatively impacted microparticle integrity, potentially increasing EO release. These findings underscore the crucial role of wall materials in shaping the physical, morphological, thermal, antioxidant, and release properties of spray-dried microparticles, offering valuable insights for microencapsulation techniques.

On moving average based location charts under modified successive sampling

Ceramics are made up of water, clay, and powders. These are categorized as non-metallic and inorganic materials. It is revealed in the literature that Longquan celadon glaze had irregular cracks in glaze layers due to the relatively high content of $Na_{2}O$. Therefore, it is necessary to monitor the influence of $Na_{2}O$ in the ceramic process. Control charts are a possible tool to monitor the changes in the ceramic process. For single event issues, simple random sampling strategy is utilized; however, modified successive sampling is preferred as the favored sampling strategy at regular intervals of time when the quality of any product is evaluated. Hence, this paper is designed to propose moving average $M{A_{MSS\left( S \right)}}$ and double moving average $DM{A_{MSS\left( S \right)}}$ based control charts to detect small to moderate location shifts using the modified successive sampling technique. We have highlighted the performance evaluations of designed control charts with respect to run-length metrics, and their comparison has been made with the existing $Shewhar{t_{MSS\left( S \right)}}\;$control chart. The results revealed that the $DM{A_{MSS\left( S \right)}}$ performs more efficiently as compared to the $Shewhar{t_{MSS\left( S \right)}}$ and $M{A_{MSS\left( S \right)}}\;$control charts. Further, to demonstrate the application of the designed charts, a dataset of the chemical composition of the ceramic is also utilized.

Interface crack analysis in 2D bounded dissimilar materials using an enriched physics-informed neural networks

This study explores the application of physics-informed neural networks (PINNs) to analyze interface crack problems within the context of elastic bimaterial fracture mechanics. Bimaterial interface cracks exhibit a distinct behavior compared to cracks in homogeneous materials, and this behavior often involves oscillatory phenomena that can pose challenges in numerical modeling. By employing neural networks for solution approximation, PINNs are meshless and are trained using batches of collocation points, which may be randomly or strategically sampled across the computational domain. To effectively capture the oscillatory singular behavior in the crack-tip regions, this paper introduces an enhanced PINNs formulation that enables the modeling of interface cracks without requiring any refinement near the crack-tip. The trainable parameters of the current PINNs are dynamically optimized throughout the training process to fulfill both the underlying differential equations and the associated initial/boundary conditions. One of the significant advantages of the present PINNs is that it uses enrichment functions to capture the behavior around the crack region, allowing for greater flexibility in handling irregular or complex crack paths. The method's accuracy and stability are validated across several benchmark examples.

A microstructure-sensitive electro-chemo-mechanical phase-field model of pitting and stress corrosion cracking

An electro-chemo-mechanical phase-field formulation is developed to simulate pitting and stress corrosion in polycrystalline materials. The formulation incorporates dependencies of mechanical properties and corrosion potential on crystallographic orientation. The model considers the formation and charging dynamics of an electric double layer through a new general boundary condition for the solution potential. The potential of the model is demonstrated by simulating corrosion in polycrystalline materials with various grain morphology distributions. The results show that incorporating the underlying microstructure yields more extensive defects, faster defect kinetics, and irregular pit and crack shapes relative to a microstructurally-insensitive homogeneous material scenario.

Crack _ PSTU: Crack detection based on the U-Net framework combined with Swin Transformer

Cracks serve as a significant indicator of aging infrastructure. While the surfaces of traditional infrastructures are visually inspected manually, this approach is labor-intensive, highly subjective, and often surpasses the capabilities of available inspection personnel. Although some researchers have employed traditional image processing and machine learning techniques to address these challenges, the presence of irregular crack shapes, complex lighting conditions, and limitations in detecting only a single type of surface crack complicate automatic crack detection. Recent research indicates that deep learning methods are increasingly leading in image-based feature extraction, object detection, and pixel attribute analysis. This paper introduces a method, Crack_PSTU (Pre-trained Swin Transformer U-Net), which leverages the U-Net framework and Swin Transformer model for infrastructure crack classification and detection tasks. Specifically, we utilize a pre-trained Swin Transformer network as the encoder and implement the decoder using convolution, pooling, and other operations, creating a "U"-shaped model architecture. Our experiments encompassed 11,298 crack images from varied scenes, with 9603 designated for training and 1695 for validation. The findings reveal that our approach surpasses other algorithms for this dataset.

Compressive Fracture Behavior and Acoustic Emission Characteristics of Sandstone under Constant Crack Water Pressure

Abstract Engineering rock containing flaws or defects under a large water source is frequently subject to the couple influence of constant crack water pressure and geostress. To investigate the fracture behavior of precracked rock under hydromechanical coupling with constant crack water pressure, compression tests were conducted on red sandstone specimens containing a single crack of different angles using a device to realize the constant crack water pressure during loading, and the failure process of rock specimens was monitored by acoustic emission (AE) technique. The results show that the presence of constant crack water pressure has a significant promotion effect on the development of shear wing cracks, and the promotion effect is influenced by the prefabricated crack angle and water pressure. As the constant crack water pressure increases, the failure mode of the 0° precrack specimen changes from “X”- shear failure to the single oblique shear failure along the shear wing crack direction, the main failure crack of the inclined precracked specimens (precrack angles of 15°, 45°, and 60°) changes from a small acute angle with the prefabricated crack to a direction along the shear wing crack, and irregular cracks occur at the chipped prefabricated crack in the 90° precracked specimen. With an increase in the constant crack water pressure, the average energy for a single hit, cumulative AE energy, and cumulative AE hits decrease, and the proportion of the tensile cracks increases and that of the shear cracks decreases.

Research on the method of loading exosomes onto absorbable stents

To explore a method of loading exosomes onto absorbable stents. By building a stent-(3-aminopropyl) triethoxysilane-1, 2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[methoxy (polyethylene glycol) 5000]-exosomes connection, the exosomes were loaded onto absorbable stents to obtained the exosome-eluting absorbable stents. The surface conditions of the stents and absorption of exosomes were observed by scanning electron microscope and identified through the time-of-flight mass spectrometry; the roughness of the stents' surfaces was observed by atomic force microscope; the appearances and sizes of the stents were observed by stereomicroscope; and the radial force was tested by tensile test machine. The absorbable stents were used as control. The scanning electron microscope observation showed that the exosome-eluting absorbable stents had some small irregular cracks on the surface where many exosomes could be seen. The atomic force microscopy observation showed that within the range of 5 μm 2, the surface roughness of the absorbable stents was ±20 nm, while the surface roughness of the exosome-eluting absorbable stents was ±70 nm. In the results of time-of-flight mass spectrometry, both the exosome-eluting absorbable stents and exosomes had a peak at the mass charge ratio of 81 (m/z 81), while the absorbable stents did not have this peak. The peak of exosome-eluting absorbable stents at m/z 73 showed a significant decrease compared to the absorbable stents. The stereomicroscope observation showed that the sizes of exosome-eluting absorbable stents met standards and the surfaces had no cracks, burrs, or depressions. The radial force results of the exosome-eluting absorbable stents met the strength standards of the original absorbable stent. By applying the chemical connection method, the exosomes successfully loaded onto the absorbable stents. And the sizes and radial forces of this exosome-eluting absorbable stents meet the standards of the original absorbable stents.

Design and evaluation of pneumatic impact‐twisting combined walnut fixed posture shell‐breaking mechanism

AbstractThe traditional walnut shelling methods, involving single‐stage or secondary processes, face challenges such as increased costs, uncertainties in shell positioning, and irregular crack expansion. To address these issues, this article introduces an innovative pneumatic impact‐twisting combined shelling method based on walnut fixed posture. The shelling mechanism design and orthogonal test were conducted, optimizing parameters like spring wire diameter (A), pressing head rotation angle (B), and cylinder locking air pressure (C) using evaluation criteria such as superior‐grade rate, intermediate‐grade rate, broken kernel rate, and shelling rate. Results indicate that the optimal shelling effect is achieved with a 3.5 mm steel spring wire diameter, a 100° downward pressing head rotation angle, and a 0.6 MPa cylinder locking air pressure on the pressure arm. The corresponding rates are as follows: superior‐grade rate 29.49%, intermediate‐grade rate 52.54%, broken kernel rate 10.14%, and shelling rate 91.04%. This study demonstrates that the pneumatic impact‐twisting combined walnut fixed posture shelling method improves post‐shelling quality, offering new design concepts for walnut shelling equipment.Practical ApplicationsThis introduces an innovative method that combines impact with twisting, and a pneumatic impact‐twisting combined walnut fixed posture shell‐breaking test device has been developed. Mechanical analysis was conducted for each stage of shell‐breaking. The research indicates that the pneumatic impact‐twisting combined method can enhance the production quality of walnut kernels after shell‐breaking. The test results indicate an improvement in the yield of 1/2 and 1/4 kernels compared to existing shell‐breaking methods. The inventive design of this shell‐breaking module contributes to the walnut kernel quality in the shell‐breaking production line, offering new methods and concepts for the design and advancement of walnut shell‐breaking devices.

Numerical investigation of two-dimensional Mode-II delamination in composite laminates

Existing standards for delamination tests on composite materials typically employ one-dimensional (1D) beam specimens. However, such specimens may not represent real delamination scenarios in composite structures, where cracks tend to propagate in two dimensions. To address this limitation and compare the delamination behavior under both 1D and two-dimensional (2D) Mode-II fracture conditions, a numerical investigation was carried out based on previous experiments. A novel cohesive zone model, considering both microcracking and fiber bridging within the fracture process zone, was developed using a semi-experimental approach and incorporated in three-dimensional finite element simulations. According to the numerical results, the investigated laminates exhibited similar maximum strain energy release rates in both 1D and 2D delamination; however, different traction-separation responses were obtained. Practical methods of locating the tip of an embedded crack were proposed based on curvature and strain measurements on the laminate surface, demonstrating potential for application in structures with irregular crack shapes.

In-situ influence of TiF3 catalyst on the hydrogen storage behavior of Mg-Ni-Y based alloy

Solid-state magnesium-based hydrogen storage encounters challenges associated with sluggish hydrogen absorption and desorption kinetics. The incorporation of catalysts is considered a promising means to improve the hydrogen absorption and desorption kinetics of these alloys. In this experiment, we prepared the Mg80Ni15Y5 alloy via vacuum melting and incorporated TiF3 in varying weight percentages of 1, 3, 5, and 7 wt% through ball milling. The phase composition and microstructure of the samples were analyzed and measured using X-ray diffraction meter (XRD), Transmission Electron Microscope (TEM), Selected Area Electron Diffraction (SAED), and Scanning Electron Microscope (SEM) techniques. The results revealed that the TiF3 introduced two catalytically phases, MgF and TiF2. And TiF2 transforms into TiH2 after hydrogen absorption, which covers the surface of MgH2 and prolongs the nucleation time of MgH2.Furthermore, the addition of TiF3 made the surface of alloy markedly coarser and more irregular and few cracks, providing channels for hydrogen diffusion. This behavior optimized the kinetic performance of the alloy. It was observed that the samples containing 7 wt%TiF3 achieved 99.2 % hydrogen saturation even in low-temperature. It's worth mentioning that the addition of 7 wt% TiF3 to the Mg80Ni15Y5 alloy significantly reduced the dehydrogenation activation energy to 58.5 kJ/mol, as opposed to pure magnesium with an activation energy of 158.2 kJ/mol. This substantial reduction has effectively accelerated the hydrogen absorption and desorption rates of the alloy. However, it had only a negligible impact on the thermodynamic properties of the sample with 7 wt%TiF3.

Weathering alterations of coal mining wastes geochemistry, petrography, and mineralogy, a case study from the Janina and Marcel Coal Mines, Upper Silesian Coal Basin (Poland)

Weathering-caused alterations in coal mining waste geochemistry, petrography, and mineralogy occurring in the known time span of 1998–2018 in the temperate climate of Poland were investigated. A series of coal mining waste rocks representing two parts of the Upper Silesian Coal Basin (USCB), differing in coalification stage, i.e., corresponding to sub-bituminous and bituminous coals, have been selected to find how the level of organic matter conditionates the weathering. Differences in organic matter content, petrographic composition, rock mineralogy and inorganic geochemistry were also taken into account. Whereas organic petrography, including vitrinite reflectance values, do not show significant weathering signs, apart from irregular cracks and, in very rare cases, paler in color oxidation rims, organic geochemistry has been affected due to low-temperature secondary processes, including increased oxygen index values, particularly in less mature coal mining wastes. Biomarker distribution has been changed to the largest extent, with partial removal of n-alkanes possibly due to biodegradation of organic matter and water-washing of lighter polycyclic aromatic hydrocarbons, including alkyl naphthalenes. Organic matter of lower maturity in coal mining wastes from the USCB eastern part, as more reactive, showed a higher level of secondary transformations. Minerals formed during weathering due to time and storage on dumps were mainly oxidation products of iron sulphides: goethite and jarosite; however, most of the minerals have not been altered. Thus, despite physical changes in coal mining wastes, such as increased brittleness, decreasing fragment size and surface color change, there are only limited changes in inorganic chemistry and mineralogy. This indicates that low-temperature processes do not favour the inorganic elements release to the environment and points out that measures to prevent self-heating within the dumps are the most vital part of post-mining activity leading to the best scenario - slow low-temperature weathering of coal mining wastes.