Partikül Takviyeli Metal Matrisli Kompozitlerin Darbe Davranışları Üzerine Bir Derleme

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A review on impact behaviors of particle reinforced metal matrix composites

Kompozit malzemeler endüstriyel uygulamalarda ani yüklenme, darbe, düşme ve çarpma gibi dinamik etkilere maruz kalabilmektedir. Bu tür etkiler tasarımda kullanılan malzemelerde gözle görülen hasara ya da görülemeyen iç hatalara sebep olmaktadır. Yapılan literatür taramaları, partikül takviyeli metal matrisli kompozitlerin darbe davranışının incelendiği çalışmaların sınırlı sayıda olduğunu göstermektedir. Gerçekleştirilen bu çalışmada, mevcut duruma dikkat çekmek istenilmiş olup konu hakkında genel bilgiler verilmiş ve son olarak da gerçekleştirilen çalışmalar özetlenmiştir. Buna göre, yapılan çalışmalarda genel olarak sıcaklığın, takviye partikül tipinin, hacim oranı ve boyutunun, ısıl işlemin ve ikincil mekanik işlemler gibi üretim parametrelerinin partikül takviyeli kompozit malzemelerin darbe dayanımına etkileri araştırılmıştır. Yapılan çalışmaların literatür açısından henüz yeterli düzeyde olmadığı tespit edilmiştir. Dolayısıyla, birçok alanda ve çok önemli uygulamalarda dinamik yükleme şartları altında kullanılan partikül takviyeli metal matrisli kompozitlerin darbe davranışları üzerine daha fazla çalışma yapılması gerektiği sonucuna varılmıştır.Composite materials can be subject to dynamic effects such as sudden loading, impact, drop and strike in industrial applications. Such effects cause visible damage or invisible internal defects in materials used in a design. Literature surveys show that the studies on the impact behavior of particle-reinforced metal matrix composites are limited. In this study, it was requested to draw attention to the current situation and the general information was given about the subject, and finally the studies carried out were summarized the literature review. Accordingly, the effects of production parameters such as temperature, reinforcement particle type, volume fraction and size, heat treatment and secondary mechanical processes on the impact strength of particulate reinforced composite materials were generally investigated in the studies carried out. It has been determined that the studies performed have not yet reached sufficient level in terms of the literature. Therefore, it has been concluded that it should be done more studies on the impact behaviors of particle-reinforced metal matrix composites used in many fields and in very important applications under the dynamic loading conditions

Low-velocity impact performance of B4C particle-reinforced Al 6061 metal matrix composites

This study addresses the effects of particle volume fraction on the low-velocity impact behavior of B4C particle-reinforced Al6061 metal matrix composites. For this purpose, Al6061 matrix B4C reinforced metal matrix composite materials were produced by powder metallurgy method. Metal matrix composite samples were produced by hot pressing in B4C particle volume fractions of 0, 5, 10 and 15%. Composite samples were subjected to impact using a drop-weight test device in a velocity of 4.55 m s(-1) with 5.045 kg striker. After low-velocity impact tests, samples were cut out for cross-sectional examination and measuring residual central transverse displacements. The results were examined in terms of contact force-time, contact force-displacement, impact energy-time curves as well as residual central transverse displacements. Also, microstructural characterizations before and after the impact tests were performed by the Scanning Electron Microscopy (SEM). It was found that metal matrix composite samples exhibited superior impact energy absorbing capacities than unreinforced material under low-velocity impact conditions. Particle volume fraction had a considerable effect on the impact strength, and thus, the impact energy absorbing capacity in composites improved with increasing the particle volume fraction. While the particle volume fraction increased, the composite structures behaved stiffer. As a result, the peak contact force was increased, and the impact durations were almost decreased. However, Al6061/B4C metal matrix composite materials having 15% volume fraction exhibited best impact performance

Low-velocity and ballistic impact resistances of particle reinforced metal-matrix composites: An experimental study

This study investigates the low-velocity and ballistic impact responses of SiC-reinforced Al6061 metal-matrix composites in different reinforcement volume fractions. Low-velocity impact (LVI) tests were performed with samples having SiC particle volume fractions of 0, 5, 10, 15, 20, 30, and 40%, while ballistic tests were carried out with samples having volume fractions of 0, 10, 20, and 30%. The weight-drop test method was used for LVI by applying 50 J (4.45 m/s) energy to all samples. Ballistic tests were carried out under the same conditions on all samples with the projectile launched at an average velocity of 500 m/s. For the determination of the ballistic resistance of the samples, the projectile penetrations in the witness structures were taken into consideration. The damage and deformations caused by both the LVI and the ballistic test in composites were examined. By the LVI test results, composite samples have absorbed less impact energy by increasing the reinforcement volume fraction, as well as demonstrated superior performance compared to unreinforced samples. In addition, the crack formation was mainly observed in the samples containing 30% reinforcement, while the composite material with a 40% volume fraction was completely broken. With the increase in the reinforcement volume fraction, the ballistic resistance of the samples increased significantly

Numerical Analysis of Impact Behavior of SiC / Al6061 Metal Matrix Composites

In this study, metal matrix composite (MMC) materials were modeled with non-linear finiteelement method and impact tests were carried out to analyze the impact behavior of MMC. Itis assumed that the composite material is produced by powder metallurgy. Al6061 and SiCwere selected for matrix and reinforcement material, respectively. 5, 10, 15% SiC reinforcedsamples were modeled as well as the control sample unreinforced sample. Tests with the weightreduction method were carried out using the ABAQUS / Explicit finite element packageprogram. For modeling, the composite samples are meshed close to the actual powder size andeach volume element is considered to be a powder grain. Powder grains are randomly selectedby means of an algorithm written with Python software, and SiC material properties are definedaccording to their volume ratios. The remaining powders have been assigned matrix materialproperty. Impact tests were carried out with 50 Joules energy. For this, a hemispherical tip with10 mm radius was used and the impact velocity was set to 4.45 m / s. Composite specimens arefixed between two clamps. The samples were modeled using an 8-node brick solid element(C3D8R), while the striker tip was modeled using the R3D4 rigid shell element. Each compositematerial consists of approximately 13750000 elements. As the damage model, Johnson Cookand Johnson Holmsquit damage parameters were defined. Each analysis was completed in 72hours on Workstation with 64GB of RAM and 40 CPUs. The impact behavior of compositematerials are interpreted by using the contact force time curves obtained from the analysis.Accordingly, an increase in the maximum contact force and a decrease in the contact time wasobserved as the reinforcing element increased. This proves that as the reinforcement ratioincreases, the composite sample takes on a stiffness structure. The maximum contact forces determined for 5, 10, 15% reinforced composites are 12.1, 15.8, 19.3 kN, respectively, whilethe contact times are 2.6, 2.41, 2.25 ms.&nbsp;</p