MARTENSITIC_TRANSFORMATION
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This document discusses martensitic transformation and the formation of martensite. It contains the following key points: 1. Martensitic transformation is a diffusionless, homogeneous deformation of the austenite lattice that changes it to the martensite lattice. It can occur due to either a very rapid or very slow transformation. 2. Habit planes form at an angle to accommodate the transformation with minimal strain energy. They are irrational planes that are approximated. 3. Glissile dislocations are necessary for the transformation, as they allow for shape changes by diffusing one part of the crystal into another without requiring diffusion. 4. Martensitic transformation involves both a volume change and
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1. Martensite forms via a diffusionless, displacive transformation in steel where the carbon remains in solid solution. It forms upon rapid quenching of austenite and has a body-centered tetragonal crystal structure.
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This document outlines experimental data requirements for friction stir processed CP Ti-Grade1 at different processing conditions. It lists the rotational speed, travel speed, and experimental tool force data required for CP Ti Gr. 1 processed at 400 rpm and 250 mm/min travel speed and also at 600 rpm and 350 mm/min travel speed if an 800 rpm option is available.
Introduction to XRD and Residual Stress Measurement
This document discusses various applications of powder x-ray diffraction including qualitative analysis, quantitative analysis, crystal structure determination, measurement of crystallite size, microstrain, and residual macrostresses. It provides examples of using powder diffraction to identify unknown materials by comparing diffraction patterns to a database, measuring residual stress through peak shifting, and analyzing thin films. Additional applications mentioned include studies of crystallinity, phase diagrams, chemical reactions, grain size, and preferred orientation.
Optimization of Spring back geometry
The document discusses geometry modeling and springback simulation using MATLAB, Python scripts, an ABAQUS ODB file, and the Fmincon optimization tool to modify an initial geometry at iterations and run simulations in ABAQUS to minimize error between the modified geometry and a desired geometry.
Optimization of Spring back geometry
The document discusses geometry modeling and simulation where MATLAB is used to modify an initial geometry, Abaqus simulation is run on the modified geometry, and the Fmincon algorithm attempts to minimize error between the simulated result and a desired geometry.
Meshfree simulation of friction stir welding process
The document discusses modeling friction stir welding and processing using smoothed particle hydrodynamics (SPH). SPH is a Lagrangian meshfree method that can simulate the large plastic deformation and material mixing of friction stir processes. Prior research has used SPH to study temperature distribution, grain size evolution, microhardness, and texture development during welding. The document outlines the governing equations of SPH and highlights several studies that have modeled friction stir welding and processing using this approach.
Pure ti electropolishing method
The document describes an electro-polishing method for Cp-Ti metal. Two Cp-Ti samples were polished at different rpm speeds of 600 and 800 under the following conditions: a voltage of 16V, flow rate of 15, time of 20 seconds, area of 0.5 cm2, and an electrolyte solution of 80% methanol and 20% perchloric acid. The samples were mechanically polished up to 9μ with 6μ diamond paste and ultrasonically cleaned in ethanol for 4 minutes before electro-polishing.
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Introduction to XRD and Residual Stress Measurement
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学校原版美国波士顿大学毕业证学历学位证书原版一模一样
原版一模一样【微信：741003700 】【美国波士顿大学毕业证学历学位证书】【微信：741003700 】学位证，留信认证（真实可查，永久存档）offer、雅思、外壳等材料/诚信可靠,可直接看成品样本，帮您解决无法毕业带来的各种难题！外壳，原版制作，诚信可靠，可直接看成品样本。行业标杆！精益求精，诚心合作，真诚制作！多年品质 ,按需精细制作，24小时接单,全套进口原装设备。十五年致力于帮助留学生解决难题，包您满意。
本公司拥有海外各大学样板无数，能完美还原海外各大学 Bachelor Diploma degree, Master Degree Diploma
1:1完美还原海外各大学毕业材料上的工艺：水印，阴影底纹，钢印LOGO烫金烫银，LOGO烫金烫银复合重叠。文字图案浮雕、激光镭射、紫外荧光、温感、复印防伪等防伪工艺。材料咨询办理、认证咨询办理请加学历顾问Q/微741003700
留信网认证的作用:
1:该专业认证可证明留学生真实身份
2:同时对留学生所学专业登记给予评定
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Comparative analysis between traditional aquaponics and reconstructed aquapon...
The aquaponic system of planting is a method that does not require soil usage. It is a method that only needs water, fish, lava rocks (a substitute for soil), and plants. Aquaponic systems are sustainable and environmentally friendly. Its use not only helps to plant in small spaces but also helps reduce artificial chemical use and minimizes excess water use, as aquaponics consumes 90% less water than soil-based gardening. The study applied a descriptive and experimental design to assess and compare conventional and reconstructed aquaponic methods for reproducing tomatoes. The researchers created an observation checklist to determine the significant factors of the study. The study aims to determine the significant difference between traditional aquaponics and reconstructed aquaponics systems propagating tomatoes in terms of height, weight, girth, and number of fruits. The reconstructed aquaponics system’s higher growth yield results in a much more nourished crop than the traditional aquaponics system. It is superior in its number of fruits, height, weight, and girth measurement. Moreover, the reconstructed aquaponics system is proven to eliminate all the hindrances present in the traditional aquaponics system, which are overcrowding of fish, algae growth, pest problems, contaminated water, and dead fish.
原版制作(Humboldt毕业证书)柏林大学毕业证学位证一模一样
原件一模一样【微信：bwp0011】《(Humboldt毕业证书)柏林大学毕业证学位证》【微信：bwp0011】学位证，留信认证（真实可查，永久存档）原件一模一样纸张工艺/offer、雅思、外壳等材料/诚信可靠,可直接看成品样本，帮您解决无法毕业带来的各种难题！外壳，原版制作，诚信可靠，可直接看成品样本。行业标杆！精益求精，诚心合作，真诚制作！多年品质 ,按需精细制作，24小时接单,全套进口原装设备。十五年致力于帮助留学生解决难题，包您满意。
本公司拥有海外各大学样板无数，能完美还原。
1:1完美还原海外各大学毕业材料上的工艺：水印，阴影底纹，钢印LOGO烫金烫银，LOGO烫金烫银复合重叠。文字图案浮雕、激光镭射、紫外荧光、温感、复印防伪等防伪工艺。材料咨询办理、认证咨询办理请加学历顾问微bwp0011
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留信网认证的作用:
1:该专业认证可证明留学生真实身份
2:同时对留学生所学专业登记给予评定
3:国家专业人才认证中心颁发入库证书
4:这个认证书并且可以归档倒地方
5:凡事获得留信网入网的信息将会逐步更新到个人身份内，将在公安局网内查询个人身份证信息后，同步读取人才网入库信息
6:个人职称评审加20分
7:个人信誉贷款加10分
8:在国家人才网主办的国家网络招聘大会中纳入资料，供国家高端企业选择人才
cnn.pptx Convolutional neural network used for image classication
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Applications of artificial Intelligence in Mechanical Engineering.pdf
Historically, mechanical engineering has relied heavily on human expertise and empirical methods to solve complex problems. With the introduction of computer-aided design (CAD) and finite element analysis (FEA), the field took its first steps towards digitization. These tools allowed engineers to simulate and analyze mechanical systems with greater accuracy and efficiency. However, the sheer volume of data generated by modern engineering systems and the increasing complexity of these systems have necessitated more advanced analytical tools, paving the way for AI.
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Software Engineering and Project Management - Introduction, Modeling Concepts...
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as Design technique: Modeling, abstraction, The Three models. Class Modeling: Object and Class Concept, Link and associations concepts, Generalization and Inheritance, A sample class model, Navigation of class models, and UML diagrams
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Null Bangalore | Pentesters Approach to AWS IAM
#Abstract:
- Learn more about the real-world methods for auditing AWS IAM (Identity and Access Management) as a pentester. So let us proceed with a brief discussion of IAM as well as some typical misconfigurations and their potential exploits in order to reinforce the understanding of IAM security best practices.
- Gain actionable insights into AWS IAM policies and roles, using hands on approach.
#Prerequisites:
- Basic understanding of AWS services and architecture
- Familiarity with cloud security concepts
- Experience using the AWS Management Console or AWS CLI.
- For hands on lab create account on [killercoda.com](https://killercoda.com/cloudsecurity-scenario/)
# Scenario Covered:
- Basics of IAM in AWS
- Implementing IAM Policies with Least Privilege to Manage S3 Bucket
- Objective: Create an S3 bucket with least privilege IAM policy and validate access.
- Steps:
- Create S3 bucket.
- Attach least privilege policy to IAM user.
- Validate access.
- Exploiting IAM PassRole Misconfiguration
-Allows a user to pass a specific IAM role to an AWS service (ec2), typically used for service access delegation. Then exploit PassRole Misconfiguration granting unauthorized access to sensitive resources.
- Objective: Demonstrate how a PassRole misconfiguration can grant unauthorized access.
- Steps:
- Allow user to pass IAM role to EC2.
- Exploit misconfiguration for unauthorized access.
- Access sensitive resources.
- Exploiting IAM AssumeRole Misconfiguration with Overly Permissive Role
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- Objective: Show how overly permissive IAM roles can lead to privilege escalation.
- Steps:
- Create role with administrative privileges.
- Allow user to assume the role.
- Perform administrative actions.
- Differentiation between PassRole vs AssumeRole
Try at [killercoda.com](https://killercoda.com/cloudsecurity-scenario/)
Embedded machine learning-based road conditions and driving behavior monitoring
Car accident rates have increased in recent years, resulting in losses in human lives, properties, and other financial costs. An embedded machine learning-based system is developed to address this critical issue. The system can monitor road conditions, detect driving patterns, and identify aggressive driving behaviors. The system is based on neural networks trained on a comprehensive dataset of driving events, driving styles, and road conditions. The system effectively detects potential risks and helps mitigate the frequency and impact of accidents. The primary goal is to ensure the safety of drivers and vehicles. Collecting data involved gathering information on three key road events: normal street and normal drive, speed bumps, circular yellow speed bumps, and three aggressive driving actions: sudden start, sudden stop, and sudden entry. The gathered data is processed and analyzed using a machine learning system designed for limited power and memory devices. The developed system resulted in 91.9% accuracy, 93.6% precision, and 92% recall. The achieved inference time on an Arduino Nano 33 BLE Sense with a 32-bit CPU running at 64 MHz is 34 ms and requires 2.6 kB peak RAM and 139.9 kB program flash memory, making it suitable for resource-constrained embedded systems.
官方认证美国密歇根州立大学毕业证学位证书原版一模一样
原版一模一样【微信：741003700 】【美国密歇根州立大学毕业证学位证书】【微信：741003700 】学位证，留信认证（真实可查，永久存档）offer、雅思、外壳等材料/诚信可靠,可直接看成品样本，帮您解决无法毕业带来的各种难题！外壳，原版制作，诚信可靠，可直接看成品样本。行业标杆！精益求精，诚心合作，真诚制作！多年品质 ,按需精细制作，24小时接单,全套进口原装设备。十五年致力于帮助留学生解决难题，包您满意。
本公司拥有海外各大学样板无数，能完美还原海外各大学 Bachelor Diploma degree, Master Degree Diploma
1:1完美还原海外各大学毕业材料上的工艺：水印，阴影底纹，钢印LOGO烫金烫银，LOGO烫金烫银复合重叠。文字图案浮雕、激光镭射、紫外荧光、温感、复印防伪等防伪工艺。材料咨询办理、认证咨询办理请加学历顾问Q/微741003700
留信网认证的作用:
1:该专业认证可证明留学生真实身份
2:同时对留学生所学专业登记给予评定
3:国家专业人才认证中心颁发入库证书
4:这个认证书并且可以归档倒地方
5:凡事获得留信网入网的信息将会逐步更新到个人身份内，将在公安局网内查询个人身份证信息后，同步读取人才网入库信息
6:个人职称评审加20分
7:个人信誉贷款加10分
8:在国家人才网主办的国家网络招聘大会中纳入资料，供国家高端企业选择人才
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MARTENSITIC_TRANSFORMATION
- 2. Martensitic transformation Habit plane This shape to reduce the strain energy Habit planes are irrational therefore approximated A homogeneous deformation of the lattice of the austenite occurs to change it to the lattice of the martensite A diffusion less transformation occurs due to either too quick transformation (steel) or due to too slow transformation (iron nickel alloy at 5 K) A homogeneous deformation of the lattice of the austenite occurs to change it to the lattice of the martensite No compositional change during transformation therefore Aust. And martensite compositions are same which can be confirmed by EDS analysis
- 3. NW vs KS OR KS relation KS OR is 5.26 more rotation in NW so that (111) α matches with the (011) γ In both cases, (011)α || (111) γ
- 4. Importance of glissile disl. In martensite transformation As glissile dislocations moves, it diffuses one part of the crystal into other hence shape change occur As glissile dislocations are necessary requirements for the martensitic transformation Do not require diffusion to move Require diffusion to move Sessile Jogs Sets cuts each other The other part pin both dislocations to move This phen. Is imp. In work hardening As glissile dislocations can not contain more than one set of the Dislocations
- 6. The only set of dislocations line must lie along the invariant line Thefore interfacial energy per unit area is very small Shear deformation γ α’
- 7. Martensitic transformation Martensitic transformation is both volume change as well as shear deformation Invariant plane Shear strain is high Volume change is low Strain energy for martensite transformation C – thickness of the plate Therefore to minimise the energy thickness is very small s; shear strain
- 8. Reason for thin plate shape in martensite and mechanical twins Although overall shear strain is uniform but since invariant plane is unchanged and to minimise the strain energy, at the corner it takes the shape of thin plate • Due to a similar reason, the mechanical twin forms plate like structure, 1. since invariant plane is unchanged at corner displacement is minimum for same shear strain, 2. To minimises the strain energy • while the annealing twins forms the slab like structure because they don’t have to accommodate the deformation
- 9. γ-α or α’ Deformation (Bain strain) Same Lattice but refined the structure as BCT FCC
- 10. Compression Expansion But we can not get invariant plane from this loading Therefore a slight rigid body rotation is required to match oa and oa’ to get invariant plane
- 11. Slipped and twinned martensite
- 12. Twins and martensite HKDH Bhadesia
- 13. Twin involves the shearing of close pack plane Twin involves the shearing of close pack plane Crystal structure of the twin is same as the crystal str. Of the matrix/ Only orientation changes
- 14. Mod-01 order-disorder transformation Ms depends upon the carbon content, alloying elemnt and grain size Smaller the gap b/w T0 and TMs, smaller the shear is requires