Mechanical Reliability Performance Research Articles

Highly Conductive Supramolecular Salt Gel Electrolyte for Flexible Supercapacitors.

Conductive gels have greatly facilitated the development of flexible energy storage devices, including supercapacitors, batteries, and triboelectric nanogenerators. However, it is challenging for gel electrolytes to tackle the trade-off issues between mechanical properties and conductivity. Herein, a strategy of all inorganic salt-driven supramolecular networks is presented to construct gel electrolytes with high conductivity and reliable mechanical performance for flexible supercapacitors. The salt gel is successfully fabricated by combining a salt supramolecular network constructed by NH4Mo7O24·4H2O and FeCl3·6H2O and a polymer network of poly(vinyl alcohol). The inorganic salt supramolecular network serves as a rigid self-supporting framework in the hydrogel system for improving the mechanical properties and providing abundant active sites for accelerating ion transport. Furthermore, the salt gel-enabled supercapacitors are equipped and exhibit a high specific capacitance (199.4 mF cm-2) and excellent energy density (27.69 μWh cm-2). Moreover, the flexible supercapacitors not only present remarkable cyclic stability after 3000 charging/discharging cycles but also exhibit good electrochemical stability even under severe deformation conditions. The strategy of salt-gel-driven flexible supercapacitors would provide fresh thinking for the development of advanced flexible energy storage fields.

Large-Scale carbon Fiber-Based Solar-Driven evaporator with 1T MoS2-MXene Heterostructure: Towards reliable mechanical performance and efficient seawater desalination

Solar-driven interfacial water evaporation is often regarded as a promising method for producing fresh water from seawater. However, developing an evaporator with an ideal evaporation rate and efficient seawater desalination capabilities remains a significant challenge, especially when considering the mechanical performance requirements in large-scale practical use. Based on this, this work proposed a Janus-structured 3D carbon fiber (CF)-reinforced solar-driven evaporator fabricated through a vacuum-assisted infusion process (VAIP). A heterogeneous structure of 1 T MoS2-MXene, formed through ion embedding, was adorned on the surface to serve as an efficient photothermal conversion material. Due to the synergistic advantages, the Janus 1 T MoS2-MXene/ CSA/CF (JMMC) evaporator achieved excellent solar absorption efficiency of 94 % in the range of 200–2500 nm. The evaporator exhibited an evaporation enthalpy as low as 1556.4 kJ·kg−1, which facilitated the escape of water molecules at the interface. The JMMC evaporator delivered a high evaporation rate of 2.29 kg m-2h−1 and an efficiency of 93.8 % under the irradiation of 1 sun (1.0 kW/m−2(−|-)). The influence of the heterogeneous structure of 1 T MoS₂-MXene on the water evaporation rate was thoroughly assessed through molecular dynamics simulations. Besides, the mechanical performance of this evaporator was highly satisfactory, rendering it suitable for application in demanding and complex usage environments. Furthermore, its remarkable conductivity facilitated an excellent Joule heating effect even at low voltages, enabling water evaporation under challenging circumstances such as overcast skies or indoor settings. The versatility of this scalable evaporator holds great promise for addressing the issue of freshwater scarcity.

Finite element analysis of the mechanical performance of self-expanding endovascular stents made with new nickel-free superelastic β-titanium alloys

New Ni-free superelastic β-titanium alloys from the Ti–Zr–Nb–Sn system have been designed in this study to replace the NiTi alloy currently used for self-expanding endovascular stents. The simulation results, carried out by finite element analysis (FEA) on two β-type Ti–Zr–Nb–Sn alloys using a commonly used superelastic constitutive model, were in good agreement with the experimental uniaxial tension data. An ad-hoc self-expanding coronary stent was specifically designed for the present study. To assess the mechanical performance of the endovascular stents, a FEA framework of the stent deployed in the arterial system was established, and a simply cyclic bending loading was proposed. Six comparative simulations of three superelastic materials (including NiTi for comparison) and two arterial configurations were successfully conducted. The mechanical behaviours of the stents were analysed through stress localization, the increase in artery diameter, contact results, and distributions of mean and alternating strain. The simulation results show that the Ti–22Zr–11Nb–2Sn (at. %) alloy composition for the stent produces the largest contact area (9.92 mm2) and radial contact force (49.5 mN) on the inner surface of the plaque and a higher increase in the stenotic artery diameter (70 %) after three vascular bending cycles. Furthermore, the Ti–22Zr–11Nb–2Sn stent exhibited sufficient crimping capacity and reliable mechanical performance during deployment and cyclic bending, which could make it a suitable choice for self-expanding coronary stents. In this work, the implementation of finite element analysis has thus made it possible to propose a solid basis for the mechanical evaluation of these stents fabricated in new Ni-free superelastic β-Ti alloys.

Process-structure-property effects of ultraviolet curing in multi-material jetting additive manufacturing

Material jetting (MJT) is an additive manufacturing process that involves selective jetting of a liquid material that is subsequently solidified, often via ultraviolet (UV) irradiation. The process presents designers with the opportunity to tune material properties on a voxel-by-voxel basis to fabricate high-resolution, multi-material parts. However, MJT is mainly constrained to prototyping and modeling applications, due to a limited selection of functional materials and challenges in attaining repeatable and reproducible part quality. Specifically, MJT’s indiscriminate UV dosing poses the risk of providing inconsistent dosing to parts, which could cause unintended variations in mechanical properties that are dependent on part design and build layout. To enable relating MJT processing conditions to final part properties, an MJT process model is presented that predicts accumulated exposure in parts of different materials, surface finishings, and build layouts by accounting for inputs relating to surface exposure, part design, and build plate configuration. Fundamentally guided by the Beer-Lambert law, the model leverages physical measurements of an MJT system, including UV spectral intensity distribution and toolpathing, to quantify cumulative exposure in batch-printed parts. Experimental characterization of parts printed in different configurations enabled correlation of parts’ total received exposure to their mechanical properties (tensile, three-point bend, Shore hardness, and dynamic mechanical analysis). It is observed that, especially in build layouts featuring multiple parts with dissimilar heights, the indiscriminate application of UV irradiation in MJT can lead to overexposure of parts, which results in changes in mechanical properties, including increased modulus and hardness. The effects of overexposure are largely dependent on material, toolpathing, and build layout. Connecting accumulated exposure to mechanical performance enables improved strategies for part design, build plate configuration, and process modification to better ensure consistency of UV dosage and reliable mechanical performance for batch-printed end-use parts.

Anisotropic highly conductive joints utilizing Cu-solder microcomposite structure for high-temperature electronics packaging

The miniaturization of power conversion systems requires high-power density operation of power modules, causing the heat-density increase. Therefore, it is essential to develop bonding technology to realize highly thermally conductive and reliable high-temperature joints. In this study, we propose a novel anisotropic microcomposite (AMC) joint that integrates a lotus-type porous Cu (LPC) sheet and Sn-based solder for high-temperature electronic applications. The AMC joint was successfully fabricated by infiltrating the molten solder into the unidirectional pores of the LPC sheet during a simple reflow process. Steady-state thermal conductivity measurements for a uniquely designed specimen revealed its equivalent thermal conductivity (142.4 W/m·K), 2.5 times higher than the solder. Finite element simulations supported its excellent thermal performance by investigating the heat flux distribution and thermal conductivity prediction that utilize a three-dimensional image-based constructed model. In addition, the aging test at 200 °C for 1008 h clarified a stable shear strength of over 46 MPa. This indicates a reliable mechanical performance at 200 °C, which is only 20 °C below the melting point of the solder. These experimental and numerical studies proved the potential of the novel joint as a high-temperature electronics joint and offered possible mechanisms for its thermal and mechanical property enhancement.

Room temperature quenching and partitioning (RT-Q&P) processed steel with chemically heterogeneous initial microstructure

Microstructure heterogeneity has been regarded as being detrimental in obtaining reliable mechanical performance of steels. However, in the present study, we demonstrated that a proactive control of microstructure heterogeneity could deliver unprecedented tensile properties that was hardly achieved by using chemically homogeneous initial microstructure. The heterogeneity of Mn distribution generated by utilizing its solubility difference between ferrite, austenite and cementite at intercritical annealing, promoted the retention of austenite in the final microstructure subjected to the room quenching and partitioning process. The enhancement of fraction as well as the stability of austenite contributed to the simultaneous improvement of tensile strength and ductility which have been regarded as mutually exclusive properties. Furthermore, even in steel with lean Mn composition, the room temperature quenching and partitioning process combined with the chemically heterogeneous initial microstructure presented tensile properties comparable to those expected in steels with much higher Mn content, which exhibited the potential of heterogeneity-driven microstructure control for the development of advanced steel products.

Experimental investigation on mechanical behavior of as cast Zn-Al-Cu/SiC/TiB2 hybrid metal matrix composite by ultrasonic assisted stir casting technique

Now a days, the Zn-Al-Cu alloy-based composites have great impact on modern trends for bearing applications because of its reliable mechanical performance. In this paper the mechanical characteristics of as cast Zn-Al-Cu alloy-based hybrid metal matrix composites have been investigated, as well as the influence of reinforcements Silicon Carbide (SiC) and Titanium Diboride (TiB2) on the composite. The ultrasonic assisted stir casting technique has been adopted for fabricating the composites with the addition of dual reinforcements like 5 wt% of SiC as constant and by varying the wt% of TiB2 as 0 wt%, 5 wt% and 10 wt%. The ceramic particles SiC and TiB2 are taken with 20 and 30 microns in size. The ASTM standards were used to conduct the different tests, and the findings demonstrate the significance of adding reinforcements to alloy and also noticeable increase in mechanical performance in terms of hardness, tensile strength, young’s modulus and impact strength. As cast Zn-Al-Cu/5 wt.% of SiC/10 wt.% of TiB2 hybrid composite gives the minimum density as 4.79 g cc−1 and maximum hardness as 156Hv.

Tribological and mechanical fracture performance of Mediterranean lignocellulosic fiber reinforced polypropylene composites

AbstractNatural fiber‐reinforced polymeric composites are considered one of the newest materials in the industry. Ecological concerns have led to a growing need of using ecofriendly materials. This work aimed to study the dynamic and quasi‐static performance as well as tribological characteristics of Mediterranean lignocellulosic fiber‐reinforced polypropylene composites. Various types of Jordanian lignocellulosic fibers were utilized in the study, namely, hay, lemon, palm, and reed. Composites with various reinforcement structures were designed, prepared, and utilized for the investigations. Wear performance and coefficient of friction as well as various mechanical performance characteristics including tensile strength, tensile modulus, elongation to break, and impact strength were performed. Results have demonstrated that composites have led to different significant characteristics. The hay/polypropylene composites were revealed to have good mechanical performance enhancements. Their maximum value of the tensile modulus was 1557.2 MPa in the case of 30 wt% fiber content. It was also demonstrated that their maximum value of toughness was about 1031 kJ/m3 in the case of 20 wt% fiber content. However, the increase of fiber loading more than 20 wt% was found to make negative effects on the toughness characteristics. Moreover, it was found that most of the considered Jordanian lignocellulosic fibers were capable of enhancing most of the mechanical performance characteristics of the composites, particularly, the stiffness property. The coefficient of friction was also found variable with fiber loading as well as fiber type. The maximum coefficient of friction value was for the composites with 30 wt% hay, while the lowest was found for composites that contained palm and reed at 10 wt%. The work had demonstrated that the features of Jordanian natural fibers were potential and competitive regarding their elasticity, toughness, interfacial adhesive potency, accessibility, and polypropylene compatibility due to their desired intrinsic mechanical characteristics. This would contribute to the finding of low‐cost environmentally friendly materials for various bio‐product applications with reliable mechanical performance, and could attribute more sustainable design possibilities.

A self-healing hydrogel electrolyte towards all-in-one flexible supercapacitors

The self-healing electrolytes play an essential role in self-healing supercapacitors. Herein, poly (vinyl alcohol)/sulphuric acid (PVA/H2SO4) hydrogel electrolytes with self-healing properties are prepared, which has been achieved by dynamic hydrogen bonds between PVA chains. The obtained PVA hydrogel displays fast self-healing capability, reliable mechanical performance (stress at 0.29 MPa after stretching to 238%) and high ionic conductivity (57.8 mS cm−1). Based on these excellent properties, an all-in-one self-healing supercapacitor is assembled by in situ polymerization of aniline on the surface of PVA/H2SO4 hydrogel electrolyte. The assembled all-in-one supercapacitor shows outstanding capacitance performance (specific capacitance 504 mF cm−2 at current density of 0.2 mA cm−2 and energy density 35 μWh cm−2 at power density 100 μW cm−2), good cycle stability (after 5000 cycles of charging and discharging, the capacitance retention rate is 77%), excellent flexibility and considerable self-healing performance (69% capacitance retention rate after the fifth self-healing cycle). This self-healing supercapacitor will promote the development of self-healing energy storage devices in wearable electronics.

Performance assessment of disc spring-based self-centering braces for seismic hazard mitigation

A novel type of self-centering bracing system employing a disc spring-based damper is presented in this study. The proposed damper employs a special detailing which enables fast assembly and reliable mechanical performance, and has high flexibilities in load resistance, deformability and energy dissipation capacity, catering to various design objectives. The working principle of the damper is first introduced, followed by a comprehensive experimental study on six full-scale damper specimens subjected to different loading protocols. The specimens exhibit very stable flag-shaped hysteretic behavior and are fully reusable with almost no damage after experiencing the considered test sequence. Reliable energy dissipation is provided by the dampers with little sensitivity to the repeated cyclic loading, where a typical equivalent viscous damping of 20% is achieved at large deformations. The work is then extended to a system level analysis, considering varying brace parameters, to evaluate the effectiveness of the self-centering bracing system in seismic control. A buckling-restrained braced frame is also included in the analysis for comparison. Among other findings, the study indicates that the fullness of the flag-shaped hysteresis is a critical factor affecting the key structural performances. In particular, decreasing the energy dissipation factor is effective in eliminating the residual deformation, but at the cost of amplified peak deformation and floor acceleration responses. A “partial self-centering” system, which allows certain static residual deformation of the brace, is found to simultaneously suppress the peak deformation, residual deformation, and peak floor acceleration.

Response of a DIN 18MnCrSiMo6-4 Continuous Cooling Bainitic Steel to Plasma Nitriding with a Nitrogen Rich Gas Composition

The use of continuous cooling bainitic steels can provide a more energy efficient manufacturing route. However, for their use in mechanical components like gears, it is necessary to improve their surface properties without impacting the core properties to guarantee reliable mechanical performance. The effect of temperature and time on the plasma nitriding response of a DIN 18MnCrSiMo6-4 steel was investigated. The plasma nitriding was performed for 3, 6 and 9 hours, at 400, 450, 500 and 550 °C, using a gas mixture composed of 76 vol.% nitrogen and 24 vol.% hydrogen. Samples were characterized before and after plasma nitriding concerning the microstructure, hardness and microhardness, fracture toughness, phase composition and residual stress states. Based on the results presented, layer growth constants (k) for different temperatures was determined. Moreover, it could be found that 500 °C gave the best results investigated here, as higher temperature took to core and surface hardness decrease. The nitrided samples with thicker compound layers presented a fracture behavior dominated by the formation of Palmqvist cracks. X-ray phase analysis indicated the formation of biphasic compound layer on the surface of all nitrided samples. The diffusion zone presented compressive residual stresses with highest values near the surface.

Preclinical Strength Checking for Artificial Pelvic Prosthesis under Multi-activities - A Case Study

Customized prostheses are normally employed to reconstruct the biomechanics of the pelvis after resection due to tumors or accidents. The objective of this study is to evaluate the biomechanics of the pelvis under different daily activities and to establish a functional evaluation methodology for the customized prostheses. For this purposes, finite element model of a healthy pelvis as well as a reconstructed pelvic model after type II+III resection were built for biomechanical study. The biomechanical performance of the healthy and reconstructed pelvic model was studied under routine activities including standing, knee bending, sitting down, standing up, walking, stair descent and stair ascent. Subsequently, the strength and stability of the prosthesis were evaluated under these activities. Results showed that, for the heathy pelvic model, the stresses were mainly concentrated around the upper part of the sacrum and the sacroiliac joint undergoing different activities, and the maximum stress occurred during stair ascent. As for the reconstructed pelvis, the stress distribution and the tendency of the maximum stress variation predicted for the bone part during all the activities were similar to those of the natural pelvic model, which indicated that the load transferring function of the reconstructed pelvis could be restored by the prosthesis. Moreover, the predicted maximum von Mises stress of the screws and prosthesis was below the fatigue strength of the 3D printed Ti-6Al-4V, which indicated the prosthesis can provide a reliable mechanical performance after implantation.

Electro-mechanical Degradation Model of Flexible Metal Films Due to Fatigue Damage Accumulation

An electro-mechanical degradation model is developed to evaluate the electronic and mechanical reliability performance of metal films due to fatigue accumulation. The model establishes the relationship between electrical resistivity and damage, which can be used to predict the change in electrical resistivity and damage evolution of metal films under fatigue loading. Based on the developed model, fatigue damage evolution and change in electrical resistivity simulation of metal films can be implemented to evaluate the electronic and mechanical reliability performance of metal films for the condition where the stress/strain level is heterogeneous. As a case study, fatigue damage evolution and change in electrical resistivity of a copper film on flexible substrate under cyclic loading is numerical analyzed and compared with experiment. It shows that the electro-mechanical degradation model and implemented simulation are effective, and can be used to evaluate the electronic and mechanical reliability performance of metal films due to fatigue accumulation reasonably.

Experimental Study on Mechanical and Sensing Properties of Smart Composite Prestressed Tendon.

It is typically difficult for engineers to detect the tension force of prestressed tendons in concrete structures. In this study, a smart bar is fabricated by embedding a Fiber Bragg Grating (FBG) in conjunction with its communication fiber into a composite bar surrounded by carbon fibers. Subsequently, a smart composite cable is twisted by using six outer steel wires and the smart bar. Given the embedded FBG, the proposed composite cable simultaneously provides two functions, namely withstanding tension force and self-sensing the stress state. It can be potentially used as an alternative to a prestressing reinforcement tendon for prestressed concrete (PC), and thereby provide a solution to detecting the stress state of the prestressing reinforcement tendons during construction and operation. In the study, both the mechanical properties and sensing performance of the proposed composite cable are investigated by experimental studies under different force standing conditions. These conditions are similar to those of ordinary prestressed tendons of a real PC components in service or in a construction stage. The results indicate that the proposed smart composite cable under the action of ultra-high pretension stress exhibits reliable mechanical performance and sensing performance, and can be used as a prestressed tendon in prestressed concrete structures.

Preparation of dual-stimuli-responsive shear stiffening polymer composite and study on its mechanic-magnetic coupling performance

A kind of innovative dual-stimuli-responsive shear stiffening polymer composite (DSR-SST) with excellent pre-magnetized enhanced (PME) effect and ideal adhesion properties was developed by dispersing NdFeB particles into shear stiffening (S-ST) polymer matrix. Owing to its S-ST characteristic, the storage modulus ( G′ ) of DSR-SST can increase from 102 Pa to 106 Pa when the shear frequency of applied stress varies from 0.1 to 100 Hz. Meanwhile, the stiffness of the multi-functional DSR-SST can also be precisely tunable by shear frequency and magnetic field. More importantly, DSR-SST with high remanence exhibits excellent PME effect in which the G′ can be directionally increased from 1.64 MPa to 2.34 MPa through 1200 mT of pre-magnetization process in short time. Additionally, the mechanism of high residual magnetization and the movement of NdFeB particle chains are proposed and discussed. Finally, the ideal cyclic stability, plastic and adhesive characteristics guarantee the composite with reliable mechanical performance and longer lifespan in safeguarding and damping.

Mechanical Analyses and Structural Design Requirements for Flexible Energy Storage Devices

AbstractFlexible energy storage devices with excellent mechanical deformation performance are highly required to improve the integration degree of flexible electronics. Unlike those of traditional power sources, the mechanical reliability of flexible energy storage devices, including electrical performance retention and deformation endurance, has received much attention. To provide the guideline for the construction design of devices, the strain distribution and failure modes in the entire architecture should be comprehensively investigated during mechanical deformation. This review mainly focuses on the mechanical deformation characterization, analysis, and structural design strategies used in recent flexible lithium‐ion batteries (LIBs) and supercapacitors (SCs). The primary theoretical calculation of bending strain in the devices is introduced first, and then several parameters to describe the bending status are summarized. Among those parameters, bending radius and its corresponding test methods and equipment are highlighted. Derivative strategies for structural design and an overview of their application progresses, such as selection of substrates, thickness of devices, employment of encapsulation, and novel architectural designs, are reviewed in detail. Finally, the challenges and prospects of flexible energy storage devices with reliable mechanical performance are discussed.

Influence of Fatigue and Bending Strain on Critical Currents of Niobium Superconducting Flexible Cables Containing Ti and Cu Interfacial Layers

Niobium is a viable material for thin-film superconducting flexible microwave cables. To aid in the design of superconducting flexible cables using Nb, it is important to evaluate not only the superconductor electrical performance, but also mechanical reliability performance since these cables should be reasonably robust when flexed. In this paper, we performed fatigue and bending tests on Nb-only and Ti/Nb/Cu multilayer signal lines on flexible Kapton substrates and measured the change in critical current ( $I_c$ ) of these wires. From the fatigue tests, $I_c$ degradation of Nb-only cables occurred at a lower number of cycles than the Ti/Nb/Cu cables. After 250 fatigue cycles, Ti/Nb/Cu wires with the thickest Ti adhesion layer and Cu capping layer exhibited the lowest $I_c$ degradation of $\sim$ 1.2% and 0% in tensile and compressive cases, respectively. From bending tests, where the sample was held in an intentionally curved configuration during testing, $I_c$ degradation of the Nb-only cables was more severe than that of the Ti/Nb/Cu cables during tensile bending and the $I_c$ of Ti/Nb/Cu cables was minimally affected during compressive bending. These results demonstrate that a Ti adhesion layer and Cu capping layer provide reliability enhancement for superconducting Nb flex cables fabricated on Kapton.

Embedded Niobium Using PI-2611 for Superconducting Flexible Cables

ABSTRACTDense, controlled-impedance, superconducting cables with small cross-sections are desirable, especially for quantum computing applications. In this study, superconductivity properties, rf microwave response and mechanical reliability performance of embedded Nb dc cables and Nb microstrip transmission line resonators with different thicknesses of polyimide PI-2611 encapsulation layers (0, 4 and 8 μm) have been investigated. Critical temperature (Tc) and critical current (Ic) of embedded Nb dc cables are ∼ 8.2 K and ∼ 0.2 A, respectively. Embedded Nb resonators yield high loaded quality factor (QL), with values as high as 14481 at ∼ 1.2 K and at a fundamental resonance of ∼ 2 GHz. From mechanical fatigue testing, we have observed that a polyimide encapsulation layer can effectively enhance the mechanical reliability of superconducting Nb flexible cables.

Stretchable Polyurethane Sponge Scaffold Strengthened Shear Stiffening Polymer and Its Enhanced Safeguarding Performance.

A simple and scalable "dip and dry" method was developed for fabricating stretchable polyurethane sponge-based polymer composite with excellent shear stiffening effect, creep resisting and adhesion property. The stiffness of the composite was tunable, the storage modulus (G') could automatically increase 3 orders of magnitude with the increasing of shear frequency, and the G'max could reach to as high as 1.55 MPa. Importantly, the composite with ideal damping capacity reduced the impact force by 2 orders of magnitude even under 26 cycles of consecutive dynamic impact loading with no obvious mechanical degradation. Moreover, an enhancing mechanism was proposed and it was found the "B-O cross bond" and the entanglement of polymer chains were attributed to the shear stiffening characteristic. Finally, the excellent adhesion ability and hydrophobicity guarantee the composite with reliable mechanical performance and longer lifespan.

Using alkali-activated natural aluminosilicate minerals to produce compressed masonry construction materials

This paper documents research that explores the possibility of alkali activating the aluminosilicate minerals reclaimed from recycled quarried soil products to produce compressed masonry construction materials. The objective of the research is to identify and optimize the principal variables affecting geopolymerization of a common quarry by-product containing montmorillonite and alkali feldspars and other minerals. The key variables optimized in the research were: type and concentration of alkali activator, optimum moisture content for compaction and geopolymerization, and curing temperature and duration. Geopolymerization of natural aluminosilicate minerals exhibiting low reactivity typically require supplementary cementitious materials to achieve high strength. In this case, however, the use of supplementary cementitious materials was eliminated by promoting nucleation in the geopolymerization reaction. The addition of 4wt.% of nanocalcite or 0.25wt.% of synthetic nanoaluminosilicates significantly improved the 1- and 7-day compressive strengths of test specimens. Finally, the total porosity and pore-size distribution of the microstructure of certain specimens were characterized. The results were correlated with water absorption and drying shrinkage performance. The results demonstrate the feasibility of alkali activating commonly-occurring, natural aluminosilicates in the soils to produce compressed masonry blocks that exhibit reliable mechanical performance without the use of Portland cement or supplemental cementitious materials.