จำนวน Repository ( 19 )
การวิเคราะห์มุมเอียงและความหนาของแผ่นเกราะที่มีผลกระทบต่อการต้านทานการเจาะทะลุของกระสุนบนแผ่นเกราะอลูมิเนียมและสแตนเลส ด้วยระเบียบวิธีไฟไนต์เอลิเมนต์
This thesis was an analysis of the significance of angle of inclination and the thickness of the armor plate on the penetration resistance of bullets on aluminum and stainless steel armor plates determined by the finite element method. In this study the information results obtained from actual firing of bulletproof armor and the finite element simulation according to NIJ 3 standards were compared to create a pattern of bulletproof and bulletproof armor using the SolidWorks program. The simulation model of the armor shooting was created by the Ansys/Explicit Dynamics program. The bullet material was 7.62 mm tungsten carbide (WC). There were three plate types used in the simulation were made of different bulletproof armor materials: 1) stainless steel SUS304 using for the plate thickness of 5 6 8 10 14 20 30 40 45 and 55 mm. 2) aluminum AL7075 using for the plate thicknesses of 6 8 10 and 20 mm. Additionally 3) tungsten carbide using for the plate thicknesses of 6 8 and 10 mm. Each of these plates had a width x length of 300 x 300 mm. The simulation models were divided into two types: Type 1 a simulation firing at one plate at a time. Type II a simulation firing at two layered plates stacked together without any gaps between plates. The front and the back plates made of stainless steel and aluminum respectively or tungsten carbide and stainless steel respectively were determined. The angles of firing at bulletproof armor were set at 0 30 and 45 degrees. The output results were that in Type I the stainless-steel plate with a thickness of 30 mm or more could resist the penetration of bullets. However in Type II 2 stacked layers of the armor plates using the front stainless plate with a thickness of only 20 mm and the back aluminum plate with a thickness of only 8 mm could provide the same constructive results as those of tungsten carbide and stainless steel plates for the front and back plates with both thickness setting at 16 mm. All of them showed the resistance of the penetration to the bullets. More observation was that the increases in angles as a result enhanced more resistance of the bulletproof plates to bullet penetration.
การวิเคราะห์พารามิเตอร์ที่มีผลกระทบต่อความสามารถในการต้านทานของการเจะทะลุของกระสุนบนผิวเกราะอะลูมิเนียมด้วยระเบียบวิธีไฟไนต์เอลิเมนต์
This research analyzes the parameters affecting the penetrating resistance of shells on the armor surface by the finite element method. In this study the results were compared with real bulletproof armor firing tests and finite element simulations. modeling of bulletproof armor using Solid Works program. Creating and simulating armor firing pattern using ANSYS Explicit Dynamic program. damage test is based on National Institute of Justice level 3 standards with material of the ammunition is 7.62 mm tungsten carbide (WC) and speed 847 + 9.1m/s. there are two types of bulletproof armor used in this simulation 1. SKD11 2. Aluminum AL7075. The simulations is into 1 category Simulation of stacked armor plates. The sizes of the armor plates are 6 8 and 10 mm and the angles of firing of bulletproof armor are 0 30 and 45 degrees. result of this simulation armor thickness and firing angle are factors of penetration resistance. when the angle of the projectile is tilted it will cause the projectile to deflect reducing the frictional contact from the impact.
ความสามารถในการดัดขึ้นรูปและกลไกความเสียหายของโลหะแผ่นอลูมิเนียม AA6016
Aluminium alloys was used in the automotive parts industry increased for compensate steel parts material due to its lightweight and good surface. Since aluminium alloys are there relatively low mechanical properties although they can be deformed easily but the major limitation is their low formability. Especially the less bending radius which is often bending surface damaged easily. In the present work five-difference ratio of sheet thickness and bending radius for study to the bendability of cold rolled aluminum alloys AA6016 at low bending radius. The bending test by Air-bending method according to ISO 7438: 2010. To compare the results every 15 degrees. The mechanical behaviour surface roughness microstructure and damage evolution in the fillet region were analysed by experimental research. The experiment clearly showed that the Spring-back angle and bendability tend to decrease as the bending angle and material thickness increase. Due to the high tensile stress on the bending surface it effected to the surface roughness increases rapidly and led to the damage on the specimen bending surface. The initial cracks occur on the middle of the outer surface curvature and propagation in the shear plane pattern to the middle of the sheet thickness along the grain boundary. This is the consequence of plastic deformation by bending test.
การวิเคราะห์พารามิเตอร์ที่มีผลกระทบต่อความสามารถในการต้านทาน ของการเจาะทะลุของกระสุนบนผิวเกราะอะลูมิเนียมด้วยระเบียบวิธีไฟไนต์เอลิเมนต์
This research analyzes the parameters affecting the penetrating resistance of shells on the armor surface by the finite element method. In this study the results were compared with real bulletproof armor firing tests and finite element simulations. modeling of bulletproof and bulletproof armor using Solid Works program. Creating and simulating armor firing pattern using ANSYS Explicit Dynamic program. damage test is based on National Institute of Justice (NIJ) level 3 standards with bullets the material of the ammunition is 7.62 mm tungsten carbide (WC). there are two types of bulletproof armor used in this simulation 1) SKD11 2) Aluminum AL7075. The simulations is into 1 category Simulation of stacked armor plates. The sizes of the armor plates are 6 8 and 10 mm and the angles of firing of bulletproof armor are 0 30 and 45 degrees. result of this simulation armor thickness and firing angle are factors of penetration resistance.
การพัฒนาโครงสร้างสองชั้นระหว่างคอมโพสิตไฮดรอกซีอะพาไทต์-อลูมินาและเซอร์โคเนียเพื่อประยุกต์ใช้ทางการแพทย์
In this work the objective is to develop the bilayer structure consisting of hydroxyapatite-alumina (HAp-Al2O3) layer and 3 mol% yttria tetragonal zirconia (TZ-3Y) layer using conventional technique consisting of the simple pressing together with pressureless sintering. In order to obtain the desired characteristics of bilayer structure layer thickness cosintering temperature and Al2O3 addition on successful fabrication of HAp-Al2O3/TZ-3Y bilayer structure are investigated. The results indicated that the HAp-10A/TZ-3Y bilayer structure was successfully fabricated by single-end die pressing the powders in hollow cylindrical graphite die under 60 MPa pressure and further wet-bag isostatically pressing in oil to 300 MPa pressure before sintering at 1200 ˚C for 1 h. It is found that an addition of 10 vol% Al2O3 into the HAp outerlayer is the essential condition to effectively suppress the differences in densification and coefficient of thermal expansion of the two layers during cosintering at 1200 oC for 1 h. The obtained HAp-10A/TZ-3Y bilayered disc has diameter of 21.0 mm HAp-10A outerlayer of 4.5 mm thick and TZ-3Y underlayer of 2.5 mm thick. The XRD pattern of the powders crushed from its HAp-10A outerlayer revealed no transformation into other new phases demonstrating that there is no reaction between HAp and Al2O3 during sintering at 1200˚C. The cross-section morphology of HAp-10A/TZ-3Y bilayered composite obtained from the SEM result revealed the porous structure with good interconnectivity. The high porous structure of the bilayered composite provided high surface area for cell attachment indicative of good cell growth and differentiation. The primary grain sizes of HAp-10A outerlayer and TZ-3Y underlayer were in the range of 1-3 um and 100-500 nm respectively. The hardness of HAp-10A layer and /TZ-3Y layer in bilayer structure varied with different layer thicknesses. Accordingly the results presented in this work demonstrated that the HAp-10A/TZ–3Y bilayered composite fabricated by simple technique has thick HAp-Al2O3 outerlayer and strong interfacial bonding between interface layers which can be tailored for specific applications