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The fracture behaviors of tungsten alloys 91W-6.3Ni-2.7Fe were investigated by tensile tests and numerical simulations. Firstly, tensile tests were conducted on the S-570 SEM with an in-situ tensile stage. With this system, the process of deformation, damage and evolution in micro-area can be tracked and recorded, and at the same time, the load-strain curve can be drawn. Secondly, the 2D finite element model of a unit cell for the tungsten alloys was established by using finite element program. By copying the unit cell model, the macro-model of the alloys was given. Dozen of cases were performed to simulate the fracture behaviors of tungsten alloys. Thirdly, the random model of the alloys was established. The fracture patterns of the alloys were investigated by the model. The interface between the tungsten particle and the matrix was explored in details. The effect of interface strength on the fracture patterns of the alloys was taken into account. A good agreement was achieved between the experimental results and the numerical predictions.

Electroless Ni-plated short carbon fiber reinforced geopolymer matrix composites with various carbon fiber/matrix interface coating thicknesses have been successfully fabricated. The influences of coating thickness on the mechanical properties and fracture behavior have been investigated by three-point bending test and scanning electron microscopy. The flexural strength and Young's modulus of Ni-plated short carbon fiber reinforced geopolymer composites exhibit maximums as the average fiber coating thickness increases, but the work of fracture has a sharp decrease, and the fracture manner changes from ductile to brittle. This is mainly attributed to the fact that the carbon fibers favor breakage rather than pulling-out during loading because of the higher interface bonding strength of fiber/matrix, and pliability of the carbon fibers decreases with the increase of the coating thickness.

In situ SEM experimental system is employed to investigate the mechanical characteristics and the fracture behavior of 91W–6.3Ni–2.7Fe tungsten alloys. The crack initiation and propagation of tungsten alloys under tensile loadings are examined. Multi-particle unit cell models containing the microstructure characteristics of tungsten alloys are established. Fixed-point iteration method is firstly used for the multi-particle unit cell's boundary condition. By adopting the method, real displacement constrained conditions are applied on the multi-particle unit cell models. The mechanical and fracture behaviors of tungsten alloys under tensile loading are simulated. The effects of tungsten content, particle shape, particle size, and interface strength on the mechanical properties of tungsten alloys are analyzed. The relationship between the mechanical behaviors and the microstructure parameters is studied. A good agreement is obtained between the experimental results and the numerical predictions, verifying the rationality of the FE models using the fixed-point iteration method.

Given that electronic components often undergo intricate thermal and mechanical loads during operation, comprehensively understanding lead-free solder, particularly solder based on $\beta$-Sn, in various complex load conditions, plays a crucial role in ensuring the structural integrity and functional reliability of integrated circuits. Therefore, investigating the mechanical properties and fracture behavior of $\beta$-Sn as a solder material holds paramount importance. In this study, we performed molecular dynamics simulations using the modified embedded atom method to investigate the mechanical properties and crack propagation of single-crystal $\beta$-Sn under different strain rates. The research findings demonstrate that as the strain rate increases, the single-crystal $\beta$-Sn exhibits elevated yield strength, fracture strength, and strain, while the elastic modulus decreases. Under higher strain rates, the relationship between dislocation density and strain rate in single-crystal $\beta$-Sn is quantitatively elucidated. The substantial increase in internal dislocation density imparts conspicuous strain hardening to the material, rendering plastic deformation more challenging. This observation sheds light on the microscale mechanism of strain hardening at the atomic level. Our results shall facilitate a deeper investigation into the mechanical behavior of single-crystal $\beta$-Sn while also paving the path for optimizing the design and application of lead-free solder materials in the electronics industry.

The automotive industries are trying to optimize the forming and process parameters to reduce the weight of vehicle. Also, these optimized results are helpful to the manufacturer during decision making, so that overall product development or manufacturing time is reduced. In this paper, comparison of the strain paths, necking and fracture behaviors among the steel materials is performed. In this paper, the formability parameters such as strain path, thinning and contact pressures between die sets are studied. The strain path points are predicted by using FEA simulation in Pamstamp software for AISI304 and AISI409L grade material. The major and minor points are predicted at necking points for various specimens and these points are represented on FLD curve for both the materials. It is observed that AISI304 grade material showed higher formability i.e. 17% higher formability than the AISI409L grade material. The simulated and experimental results showed a closed match with good correlations though the variation between them is nearly 7%. Also, the microstructures are investigated by following standard metallographic process and after investigation it is observed that as the microstructure changes the locations of the deformed sheet parts also get changed.

Recent works verified that network reinforcement design enhanced the modulus and strength of discontinuously reinforced metal–matrix composites (MMCs). The particle size ratio (PSR), i.e., the ratio of matrix to reinforcement particle diameters, defines the particle clustering degree and is an important network parameter. The effects of PSR on the mechanical properties of network SiCp/Al composites were studied via finite element analysis. The results showed that the composites with PSR $\le 7$:1 exhibited similar mechanical property. In contrast, composites with PSR $\ge 8$:1 showed enhanced modulus (87.5–89.5GPa) and yield strength (303–315MPa) over homogeneous composites (modulus 75.9GPa and yield strength 299MPa). The enhanced mechanical properties were attributed to the higher load-bearing capacity of the reinforcement walls parallel to the load direction (PaW). However, premature failure and thus reduced elongation occurred with PSR $\ge 7$:1 because network layers perpendicular to the load direction (PeW) acted as crack propagation paths. So, a threshold PSR of 7:1–8:1 was proposed for effective network design. The sacrifice of elongation needs to be solved for optimized network architecture designs.

Lightweight materials such as aluminum alloys are, nowadays, well recognized as one of the most popular choices in the aerospace industry owing to their fantastic strength-to-weight ratio. Their fabricability is, nevertheless, doubtful down to their low elongation, especially in the present day where geometrical complexity is hugely demanded. Truly understanding fracture behaviors of such sheet metal would benefit all involved parties. To achieve that challenging goal, proper fracture-analysis models and implementation methods are definitely crucial. This work proposes the recent Lou–Huh fracture criterion to describe the rupture behavior of sheet aluminum alloy AA2024-T3. To build such a damage mechanics model, a string of Nakajima stretching and notched tensile tests must be performed to acquire critical strain data, precisely measured using the 2D-DIC principle. The data are used to calibrate the model. A fracture locus (FL), defining an extensive AA2024-T3 fracture threshold, is then established out of the fine-tuned model. The FL is directly coupled into an ABAQUS/Explicit FE process simulation model via the Fortran-based subroutine VUMAT. This leading-edge implementation can supposedly emulate realistic damage evolution by monitoring and actively removing the elements whose degree of injury has reached a certain limit. At the end, the complete integrative FE model is empirically validated through an industrial X-shaped specimen, deformed under nonlinear strain paths. Fracture locations, shapes and development on the FE-simulated specimen are observed and contrasted with those on the experimental one. It is obviously shown that the results from both approaches agree remarkably well in all aspects. When compared with the famous fracture forming limit curve (FFLC), the Lou–Huh FL combined with the element-removal VUMAT implementation clearly outperforms. In summary, the proposed model and the implementation procedure are practically outstanding fracture evaluators of AA2024-T3, wonderfully predicting and vividly laying bare crack appearance and growth.

The fracture behaviors of tungsten alloys 91W-6.3Ni-2.7Fe were investigated by tensile tests and numerical simulations. Firstly, tensile tests were conducted on the S-570 SEM with an in-situ tensile stage. With this system, the process of deformation, damage and evolution in micro-area can be tracked and recorded, and at the same time, the load-strain curve can be drawn. Secondly, the 2D finite element model of a unit cell for the tungsten alloys was established by using finite element program. By copying the unit cell model, the macro-model of the alloys was given. Dozen of cases were performed to simulate the fracture behaviors of tungsten alloys. Thirdly, the random model of the alloys was established. The fracture patterns of the alloys were investigated by the model. The interface between the tungsten particle and the matrix was explored in details. The effect of interface strength on the fracture patterns of the alloys was taken into account. A good agreement was achieved between the experimental results and the numerical predictions.