In this work, the mechanical properties and microstructural features of an AISI 304L stainless steel in two presentations, bulk and fibers, were systematically studied in order to establish the relationship among microstructure, mechanical properties, manufacturing process and effect on sample size. The microstructure was analyzed by XRD, SEM and TEM techniques. The strength, Young’s modulus and elongation of the samples were determined by tensile tests, while the hardness was measured by Vickers microhardness and nanoindentation tests. The materials have been observed to possess different mechanical and microstructural properties, which are compared and discussed.

The control of a homogeneous distribution of the reinforcing phase in aluminum matrix composites is the main issue during the synthesis of this kind of material. In this work, 2024 aluminum matrix composites reinforced with boron carbide were produced by mechanical milling, using 1 and 2 h of milling. After milling, powdered samples were cold consolidated, sintered and T6 heat treated. The morphology and microstructure of Al2024/B₄C composites were investigated by scanning electron microscopy; analysis of X-ray diffraction peaks were used for the calculation of the crystallite size and microstrains by the Williamson–Hall method. The mechanical properties were evaluated by compression and hardness tests. B₄C particles were found to be well dispersed into the aluminum matrix as a result of the high-energy milling process. The crystallite size of composites milled for 2 h was lower than those milled for 1 h. The hardness, yield strength and maximum strength were significantly improved in the composites processed for 2 h, in comparison to those processed for 1 h and the monolithic 2024 alloy.

The success of orthopedic implants critically depends on achieving mechanical and biological compatibility with bone tissue. Traditional titanium implants often suffer from high stiffness, which induces stress shielding, a phenomenon that compromises implant integration and accelerates prosthetic loosening. This study introduces an innovative approach to mitigate these limitations by engineering a porous titanium substrate with a controlled microstructure. Utilizing sodium chloride as a spacer holder, an elution and sintering process was applied at 1250 °C under high vacuum conditions to reduce the material’s elastic modulus. By manipulating NaCl volume fractions (20%, 25%, 30%, and 35%), porous titanium samples were created with elastic moduli between 16.37 and 22.56 GPa, closely matching cortical bone properties (4 to 20 GPa). A hydroxyapatite coating applied via plasma thermal spraying further enhanced osseointegration of the material. Comprehensive characterization through X-ray diffraction, scanning electron microscopy, and compression testing validated the material’s structural integrity. In vitro cytotoxicity assessments using osteoblast cells demonstrated exceptional cell viability exceeding 70%, confirming the material’s biocompatibility. These findings represent a significant advancement in biomaterial design, offering a promising strategy for developing next-generation joint prostheses with superior mechanical and biological adaptation to bone tissue.

The cement industry contributes approximately 7% of global anthropogenic CO₂ emissions, primarily through energy-intensive clinker production. This study evaluates the thermal behavior and gas emissions of seven waste materials (sawdust, pecan nutshell, wind blade waste, industrial hose waste, tire-derived fuel, plastic waste, and automotive shredder residue) as alternative fuels for cement manufacturing, motivated by the limited information available regarding their performance and environmental impact, with bituminous coal used as a reference. Thermogravimetric analysis and differential scanning calorimetry (TGA-DSC) were used to quantify mass loss and energy changes, while TGA coupled with mass spectrometry (TGA-MS) was used to identify volatile compounds released during thermal degradation. Both TGA-DSC and TGA-MS were conducted under oxidative conditions. The analysis revealed that these waste materials can generate up to 70% of coal’s energy, with combustion primarily occurring between 200 °C and 600 °C. The thermal profiles demonstrated that these materials can effectively replace fossil fuels without releasing harmful toxic gases like HCl, dioxins, or furans. Combustion predominantly emitted CO₂ and H₂O, with only trace volatile organic compounds such as C₃H₃ and COOH. The findings highlight the potential of alternative fuels to provide substantial energy for cement production while addressing waste management challenges and reducing the industry’s environmental impact through innovative resource valorization.

The cement industry accounts for approximately 7% of global CO₂ emissions, with fuel combustion contributing 40% of sectoral emissions. Alternative fuels from industrial and municipal waste offer emission reduction opportunities while addressing waste management challenges. This study quantifies real-time gaseous emissions (CO₂, CO, NO_x, and SO₂) from seven alternative fuels—sawdust (SD), pecan nutshell (PNS), wind blade waste (WBW), industrial hose waste (IHW), tire-derived fuel (TDF), plastic waste (PW), and automotive shredder residue (ASR)—during calcination at 850 °C. Bituminous coal served as the reference fuel. Gas concentrations were continuously monitored using the testo 350 portable gas analyzer. Emission factors were calculated on a mass basis (kg/kg fuel) and energy basis (kg/GJ) for standardized comparisons. Alternative fuels consistently produced lower CO₂ emission factors than coal, with biomass-derived fuels (SD and PNS) showing reductions of 45% and 38%, respectively. Most alternative fuels generated lower CO and NO_x emissions per unit energy due to their higher volatile matter content, promoting complete combustion. TDF was an exception, exhibiting 2.8 times higher CO emissions. SO₂ emissions were negligible except in the case of TDF (0.14% sulfur content). The measured emission factors were 15–30% lower than theoretical IPCC values, confirming the environmental viability of alternative fuels as coal substitutes in cement production.